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Filed Pursuant to Rule 424(b)5
Registration No. 333-209367

PROSPECTUS SUPPLEMENT
(To Prospectus dated February 11, 2016)

16,666,667 Shares of Common Stock
Warrants to Purchase 16,666,667 Shares of Common Stock

Egalet Corporation

         We are offering 16,666,667 shares of our common stock, par value $0.001 per share, and warrants to purchase up to 16,666,667 shares of common stock (and the shares of common stock that are issuable from time to time upon exercise of the warrants) pursuant to this prospectus supplement and the accompanying prospectus. The shares of common stock and the warrants will be sold in combination, with one warrant to purchase one share of common stock accompanying each share of common stock sold. The combined purchase price for each share of common stock and accompanying warrant is $1.80.

         Each warrant will have an exercise price of $2.70 per share of common stock, will be exercisable upon issuance and will expire five years from the date of issuance. The shares of common stock and the warrants are immediately separable and will be issued separately, but must be purchased together in this offering.

         Our common stock is listed on The NASDAQ Global Market under the symbol "EGLT." The last reported sale price of our common stock on The NASDAQ Global Market on July 5, 2017, was $2.54 per share. There is no established trading market for the warrants and we do not expect a market to develop. In addition, we do not intend to list the warrants on The NASDAQ Global Market, any other national securities exchange or any other nationally recognized trading system. The warrants will be issued in book-entry form with Broadridge Corporate Issuer Solutions, Inc. as warrant agent.

         We are an "emerging growth company" under applicable Securities and Exchange Commission rules and are eligible for reduced public company disclosure requirements. See "Prospectus Supplement Summary—Implications of Being an Emerging Growth Company.

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         Investing in our common stock and the accompanying warrants involves a high degree of risk. See "Risk Factors" on page S-5 of this prospectus supplement, page 4 of the accompanying prospectus and in the documents we incorporate by reference in this prospectus supplement to read about factors you should consider before buying shares of our common stock and accompanying warrants.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

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         The above summary of offering proceeds to us does not include any proceeds that may be received by us upon any exercise of the warrants being issued in this offering.

         We have granted the underwriter an option for a period of 30 days to purchase up to an additional 2,500,000 shares of our common stock and additional warrants to purchase 2,500,000 shares of our common stock. If the underwriter exercises the option in full, the total underwriting discounts and commissions payable by us will be $1,380,000.02, and the total proceeds to us, before expenses, will be $33,120,000.58.

         The underwriter expects to deliver the shares of common stock and accompanying warrants against payment on or about July 11, 2017.

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Sole Book-Running Manager

Cantor Fitzgerald & Co.

   

The date of this prospectus supplement is July 6, 2017.

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EXPLANATORY NOTE

        Unless the context otherwise requires or as otherwise indicated, as used in this prospectus supplement and the accompanying prospectus, references to the "Company", "we", "us" and "our" refer to Egalet Corporation and its subsidiaries. The Egalet logo is our trademark and Egalet is our registered trademark. All other trade names, trademarks and service marks appearing in this prospectus supplement and the accompanying prospectus are the property of their respective owners. We have assumed that the reader understands that all such terms are source-indicating. Accordingly, such terms, when first mentioned in this prospectus supplement or the accompanying prospectus, appear with the trade name, trademark or service mark notice and then throughout the remainder of this prospectus supplement and the accompanying prospectus without the trade name, trademark or service mark notices for convenience only and should not be construed as being used in a descriptive or generic sense. Unless otherwise indicated, all statistical information provided about our business in this prospectus supplement and the accompanying prospectus is as of March 31, 2017.

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PROSPECTUS SUPPLEMENT

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ABOUT THIS PROSPECTUS SUPPLEMENT

        This prospectus supplement and the accompanying prospectus are part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, using a "shelf" registration process. We provide information to you about this offering of shares of our common stock and accompanying warrants in two separate documents that are bound together: (1) this prospectus supplement, which describes the specific details regarding this offering; and (2) the accompanying base prospectus, which provides general information, some of which may not apply to this offering. Generally, unless the context indicates otherwise, when we refer to this "prospectus," we are referring to both documents combined, as well as the information incorporated herein by reference. If information in this prospectus supplement is inconsistent with the accompanying base prospectus, you should rely on this prospectus supplement. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date (for example, a document incorporated by reference in this prospectus supplement), the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates. You should also read and consider the additional information under the captions "Information Incorporated by Reference and Available Information" in this prospectus supplement.

        In making your investment decision, you should rely only on the information contained or incorporated by reference in this prospectus supplement, in the accompanying base prospectus and in any free writing prospectus with respect to this offering filed by us with the SEC. We have not authorized any person to provide you with different or additional information. If anyone provides you with different, additional or inconsistent information, you should not rely on it. You should assume that the information appearing in this prospectus supplement, the accompanying base prospectus, any free writing prospectus with respect to the offering filed by us with the SEC and the documents incorporated by reference herein and therein is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since those dates.

        Neither we nor any of the underwriters have authorized anyone to provide information different from that contained in this prospectus. When you make a decision about whether to invest in our common stock and accompanying warrants, you should not rely upon any information other than the information in this prospectus. Neither the delivery of this prospectus nor the sale of our common stock and accompanying warrants means that information contained in this prospectus is correct after the date of this prospectus. This prospectus is not an offer to sell or solicitation of an offer to buy these shares of common stock and accompanying warrants in any circumstances under which the offer or solicitation is unlawful.

        We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. In addition, the assertions embodied in any representations, warranties and covenants contained in such agreements may be subject to qualifications with respect to knowledge and materiality different from those applicable to investors and may be qualified by information in disclosure schedules. These disclosure schedules may contain information that modifies, qualifies and creates exceptions to the representations, warranties and covenants set forth in the agreements. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

        We obtained the industry, market and competitive position data in this prospectus from our own internal estimates and research, as well as from industry and general publications and research surveys

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and studies conducted by third parties. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the industry in which we operate is necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in "Risk Factors" and elsewhere in this prospectus. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and us.

        We are offering to sell, and seeking offers to buy, our securities only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying base prospectus and the offering of our securities in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying base prospectus must inform themselves about, and observe any restrictions relating to, the offering of our securities and the distribution of this prospectus supplement and the accompanying base prospectus outside the United States. This prospectus supplement and the accompanying base prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying base prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

        In this prospectus, we use the term "day" to refer to a calendar day, and we use the term "business day" to refer to any day other than Saturday, Sunday, a legal holiday or a day on which banks in New York City are authorized or required to close.

        We have filed or incorporated by reference exhibits to the registration statement of which this prospectus forms a part. You should read the exhibits carefully for provisions that may be important to you.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus supplement and the accompanying prospectus includes forward-looking statements. We may, in some cases, use terms such as "believes," "estimates," "anticipates," "expects," "plans," "intends," "may," "could," "might," "will," "should," "approximately" or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. Forward-looking statements appear in a number of places throughout this prospectus supplement and the accompanying prospectus and include statements regarding our intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things, the commercial success of our products and, if approved, our product candidates, our plans with regard to the commercialization of our products, including our ability to execute on our sales and marketing strategy, our ongoing and planned preclinical development and clinical trials, the timing of and our ability to make regulatory filings and obtain and maintain regulatory approvals for our product candidates, our intellectual property position, the degree of clinical utility of our products, particularly in specific patient populations, current and future government regulations and the impact of such regulations, expectations regarding clinical trial data, our business development plans, our results of operations, cash needs and ability to obtain additional funding, financial condition, liquidity, prospects, growth and strategies, foreign exchange rates, the industry in which we operate and the trends that may affect the industry or us.

        By their nature, forward-looking statements involve risks and uncertainties because they relate to events, competitive dynamics and industry change, and depend on the economic circumstances that may or may not occur in the future or may occur on longer or shorter timelines than anticipated. Although we believe that we have a reasonable basis for each forward-looking statement contained in this prospectus, we caution you that forward-looking statements are not guarantees of future performance and that our actual results of operations, financial condition and liquidity, and the development of the

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industry in which we operate, may differ materially from the forward-looking statements contained in this prospectus supplement and the accompanying prospectus. In addition, even if our results of operations, financial condition and liquidity, and the development of the industry in which we operate are consistent with the forward-looking statements contained in this prospectus supplement and the accompanying prospectus, they may not be predictive of results or developments in future periods.

        Actual results could differ materially from our forward-looking statements due to a number of factors, including risks related to:

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our estimates regarding expenses, future revenues, capital requirements and needs for additional financing;



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our current and future indebtedness;



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our ability to obtain additional financing;



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the level of commercial success of our products and, if approved, our product candidates;



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our ability to execute on our sales and marketing strategy, including developing relationships with customers, physicians, payors and other constituencies;



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the continued development of our currently limited commercialization capabilities, including sales and marketing capabilities and the outcome of the internalization of our previously external sales force;



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the success and timing of competing products that are or become available;



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the accuracy of our estimates of the size and characteristics of the potential markets for our product candidates and our ability to serve those markets;



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the rate and degree of market acceptance of our products and product candidates;



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the difficulties in obtaining and maintaining regulatory approval of our products and product candidates, and any related restrictions, limitations and/or warnings in the product label under any approval we may obtain;



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the performance of third parties, including contract research organizations, manufacturers and collaborators;



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our success with regard to any business development initiatives;



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the success and timing of our preclinical studies and clinical trials;



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our ability to recruit or retain key scientific or management personnel or to retain our executive officers;



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regulatory developments in the United States and foreign countries;



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obtaining and maintaining intellectual property protection for our products and product candidates and our proprietary technology;



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our ability to operate our business without infringing the intellectual property rights of others;



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recently enacted and future legislation regarding the healthcare system; and



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our ability to integrate and grow any businesses or products that we may require.

        You should also read carefully the factors described in the "Risk Factors" section of this prospectus supplement and the accompanying prospectus to better understand the risks and uncertainties inherent in our business and underlying any forward-looking statements. As a result of these factors, we cannot assure you that the forward- looking statements in this prospectus supplement

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and the accompanying prospectus will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not place undue reliance on these statements or regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified timeframe, or at all.

        Any forward-looking statements that we make in this prospectus supplement and the accompanying prospectus speak only as of the date of such statement, and, except as required by applicable law, we undertake no obligation to update such statements to reflect events or circumstances after the date of this prospectus supplement and the accompanying prospectus or to reflect the occurrence of unanticipated events. Comparisons of results for current and any prior periods are not intended to express any future trends or indications of future performance, unless expressed as such, and should only be viewed as historical data.

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RISK FACTORS

        Investing in our securities involves a high degree of risk. You should carefully consider the risks described below and under the section captioned "Risk Factors" contained in the accompanying prospectus and in our Annual Report on Form 10-K for the year ended December 31, 2016, as revised and supplemented by our Quarterly Report on Form 10-Q for the quarter ended March 31, 2017, each of which is incorporated by reference herein, together with the other information contained or incorporated by reference in this prospectus supplement before making a decision to invest in our common stock and accompanying warrants. We cannot assure you that any of the events discussed in the risk factors below will not occur. These risks could have a material and adverse impact on our business, results of operations, financial condition and cash flows, and our future prospects would likely be materially and adversely affected. If that were to happen, the trading price of our common stock could decline, and you could lose all or part of your investment. The risks discussed below also include forward-looking statements and our actual results may differ substantially from those discussed in these forward-looking statements. See "Special Note Regarding Forward-Looking Statements."

Risks Related to the Offering

Sales of a substantial number of shares of our common stock, or the perception that such sales might occur, could adversely affect the trading price of our common stock.

        As of June 22, 2017, we had 26,335,983 shares of our common stock outstanding. Also, we had, as of June 22, 2017, 4,830,312 shares of our common stock issuable upon the exercise of outstanding options, and up to 4,102,496 shares of our common stock issuable upon conversion of the Convertible Notes. After this offering, we will have 43,002,650 shares of common stock outstanding (assuming no exercise of the underwriter's option and that none of the warrants issued in this offering are exercised). Many of the outstanding shares of our common stock are, and all of the shares sold in this offering upon issuance will be, freely tradable without restriction or further registration under the Securities Act. The issuance of new shares of our common stock in this offering, and the potential issuance of additional shares of our common stock upon exercise of the accompanying warrants offered in this offering, could result in resales of our common stock by our current stockholders concerned about the potential dilution of their holdings. In turn, these resales could have the effect of depressing the market price for our common stock. A substantial majority of the outstanding shares of our common stock is, and all of the shares sold in this offering upon issuance will be, freely tradable without restriction or further registration under the Securities Act. We have filed registration statements on Form S-8 under the Securities Act covering all of the common stock subject to outstanding equity awards, as well as options and shares reserved for future issuance, under our 2013 Plan, Inducement Plan and Employee Stock Purchase Plan. A substantial portion of the outstanding shares of our common stock is, and the common stock underlying equity awards upon vesting and issuance and all of the shares sold in this offering upon issuance will be, freely tradable without restriction or further registration under the Securities Act unless these shares are owned or purchased by "affiliates" as that term is defined in Rule 144 under the Securities Act ("Rule 144"). Of our shares outstanding as of June 22, 2017, 1,923,077 are subject to a contractual lock-up with the underwriters for this offering for a period of 90 days following this offering.

        These shares can be sold, subject to any applicable volume limitations under federal securities laws, after the earlier of the expiration of, or release from, the 90-day lock-up period. Sales of a substantial number of shares of our common stock, or the perception that such sales might occur, could adversely affect the trading price of our common stock. Further, sales of shares underlying stock options or the conversion of our Convertible Notes into shares of common stock, or the perception in the market that the holders of a large number of shares intend to sell shares or that large number of convertible noteholders intend to convert their notes, could reduce the market price of our common stock. We cannot predict the effect, if any, that market sales of shares of our common stock or the

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availability of those shares of common stock for sale will have on the market price of our common stock.

Our stock price has been and may in the future be extremely volatile and our common stock has historically been traded at low volume levels, which may make it difficult for our stockholders to sell our common stock when desired or at attractive prices. As a result, you may lose all or a significant portion of your investment.

        The market price of our common stock has been highly volatile. Since our initial public offering in February 2014, the closing sales price of our common stock have ranged from a high of $18.83 per share to a low of $1.63 per share. The stock market in general has also experienced periods of significant price and volume fluctuations, and the market prices of biotechnology companies in particular have historically been highly volatile, at times for reasons that have been unrelated to the operating performance of particular companies. In addition to this market risk, the market price for our common stock could fluctuate due to a number of factors such as those listed in the section titled "Risk Factors" in our Annual Report on Form 10-K, some of which are beyond our control, including:

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the level of commercial success of our products and, if approved, our product candidates;



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the rate and degree of market acceptance of our products and product candidates;



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the accuracy of our estimates of the size and characteristics of the potential markets for our product candidates and our ability to serve those markets;



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the success and timing of our preclinical studies and clinical trials;



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the difficulties in obtaining and maintaining regulatory approval of our products and product candidates, and any related restrictions, limitations and/or warnings in the product label under any approval we may obtain;



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obtaining and maintaining intellectual property protection for our products and product candidates and our proprietary technology;



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our ability to operate our business without infringing the intellectual property rights of others



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our estimates regarding expenses, future revenues, capital requirements and needs for additional financing;



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our current and future indebtedness; and



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our use of proceeds from this offering.

        Further, our common stock has historically been traded at low volume levels and may continue to trade at low volume levels. As a result, any large purchase or sale of our common stock could depress the price of our common stock, making it difficult for investors to sell our common stock in the market without depressing the market price for the common stock or at all.

        As a result of the foregoing, investors may not be able to resell their shares at or above the price they paid for such shares. Investors in our common stock must be willing to bear the risk of fluctuations in the price of our common stock and the risk that the value of their investment in our stock could decline.

You will experience immediate and substantial dilution in the value of the securities you purchase and may experience further dilution in the future as a result of equity offerings and other issuances of our common stock or other securities.

        The offering price of our common stock and accompanying warrants being offered is substantially higher than the net tangible book value per share of our common stock outstanding prior to this offering. Therefore, assuming we sell all of the securities in this offering at the public offering price of

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$1.80 per share, after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us, you will experience immediate dilution of approximately $1.65 per share, representing the difference between our as adjusted net tangible book value per share as of March 31, 2017 after giving effect to this offering and the public offering price, without giving effect to the potential exercise of the warrants being offered in this offering. For a further description of the dilution that you will experience immediately after this offering, see the section titled "Dilution."

        To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at a lower price than the price per share in this offering. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, or that investors purchasing shares or other securities in the future will not have rights superior to our existing stockholders.

        As of June 22, 2017, there were outstanding options representing the right to purchase a total of 4,830,312 shares of our common stock at a weighted average exercise price of $6.72 per share, 99,755 shares of our common stock reserved for future issuance under the 2013 Plan, 697,167 shares of our common stock reserved for future issuance under the Employee Stock Purchase Plan, 97,500 shares of our common stock reserved for future issuance under the Inducement Plan and up to 4,102,360 shares of our common stock issuable upon conversion of the Convertible Notes. You will incur dilution upon exercise of any outstanding stock options or upon the issuance of shares of common stock under our stock incentive programs.

The warrants are a risky investment. You may not be able to recover your investment in the warrants, and the warrants may expire worthless.

        Whether the warrants will have any value will depend on, among other things, the commercial success of our products, the development of our clinical product candidates, our business development efforts and market conditions generally, which conditions will depend on factors related and unrelated to the success of our products, our product candidates and our business development efforts, and cannot be predicted at this time.

        If our common stock price does not increase to an amount sufficiently above the exercise price of the warrants during the period the warrants are exercisable, you will be unable to recover any of your investment in the warrants. There can be no assurance that any of the factors that could impact the trading price of our common stock will result in the trading price increasing to an amount that will exceed the exercise price or the price required for you to achieve a positive return on your investment in the warrants.

Holders of the warrants will have no voting rights as common stockholders until they acquire our common stock.

        Until you acquire shares of our common stock upon exercise of the warrants, you will have no voting rights with respect to our common stock issuable upon exercise of the warrants. Upon exercise of your warrants, you will be entitled to exercise all the voting rights of a common stockholder only as to matters for which the record date occurs after the exercise date.

Significant holders or beneficial holders of our common stock may not be permitted to exercise warrants that they hold.

        The warrant agreement governing the warrants being offered hereby will prohibit a holder from exercising its warrants if doing so would result in such holder (together with such holder's affiliates and any other persons acting as a group together with such holder or any of such holder's affiliates) beneficially owning more than 4.99% of our common stock outstanding immediately after giving effect

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to the exercise, provided that, at the election of a holder and notice to us, such beneficial ownership limitation shall be 9.99% of our common stock outstanding immediately after giving effect to the exercise. As a result, if you hold a significant amount of our securities, you may not be able to exercise your warrants for shares of our common stock, in whole or in part, at a time when it would be financially beneficial for you to do so.

We may not have the sufficient resources to repurchase the warrants.

        Under certain circumstances, if a "Fundamental Transaction" (as defined in the warrant agreement) occurs, holders of the warrants may require us to repurchase the remaining unexercised portion of such warrants for an amount of cash equal to the value of the warrant as determined in accordance with the Black Scholes option pricing model and the terms of the warrants. Our ability to repurchase the warrants upon such an event will depend on our available cash resources at such time, which will also be subject to general economic, financial, competitive, legislative and regulatory factors and other factors that are beyond our control. We cannot assure you that we will maintain sufficient cash reserves or that our business will generate cash flow from operations at levels sufficient to permit us to repurchase the warrants.

The warrants will contain anti-dilution provisions which may affect the our ability to secure future equity financing or reduce the proceeds of any equity financings that would otherwise be available to us.

        The warrants contain anti-dilution provisions which provide that any new issuances of common stock or securities convertible into common stock at a price, exercise price or conversion price below those of the warrants will result in the exercise price of the warrants being reduced based upon the number of securities issued in such issuance and the number of shares of the Company's common stock then outstanding. These anti-dilution provisions may affect our ability to secure future equity financing or reduce the proceeds of any equity financings that would otherwise be available to us.

There is no public market for the warrants to purchase shares of common stock being offered in this offering.

        There is no established public trading market for the warrants being offered in this offering, and we do not expect a market to develop. In addition, we do not intend to apply to list the warrants on any national securities exchange or other nationally recognized trading system, including The NASDAQ Global Market. Without an active market, the liquidity of the warrants will be limited.

We will have broad discretion in the use of the net proceeds from this offering and may allocate the net proceeds from this offering in ways that you and other stockholders may not approve.

        Our management will have broad discretion in the use of the net proceeds, including for any of the purposes described in the section entitled "Use of Proceeds," and you will not have the opportunity as part of your investment decision to assess whether the net proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. The failure of our management to use these funds effectively could have a material adverse effect on our business, cause the market price of our common stock to decline and delay the development or commercialization of our products and product candidates. Pending their ultimate use, we intend to invest the net proceeds in short-term, investment-grade, interest-bearing instruments. We may also use a portion of the net proceeds to acquire or invest in complementary businesses, products, and technologies. These investments may not yield a favorable return to our stockholders.

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Because we do not intend to declare cash dividends on our shares of common stock in the foreseeable future, stockholders must rely on appreciation of the value of our common stock for any return on their investment and may not receive any funds without selling their shares.

        We have never declared or paid cash dividends on our common stock and do not anticipate declaring or paying any cash dividends in the foreseeable future. In addition, the terms of any existing or future debt agreements may preclude us from paying dividends. As a result, we expect that only appreciation of the price of our common stock, if any, will provide a return to investors in this offering for the foreseeable future. In addition, because we do not pay cash dividends, if our stockholders want to receive funds in respect of our common stock, they must sell their shares to do so.

Servicing our $141 million aggregate principal amount of debt and related obligations requires a significant amount of cash, and we may not have sufficient cash flow from our operations to pay our substantial debt.

        In April 7, 2015, we issued $61.0 million aggregate principal amount of 5.50% Convertible Senior Notes due 2020 (the "Convertible Senior Notes"). As of March 31, 2017, $61.0 million of principal amount of the Convertible Senior Notes remained outstanding. On August 31, 2016, we completed the initial closing of our offering of up to $80.0 million aggregate principal amount of our Senior Secured Notes and entered into an indenture governing the Senior Secured Notes with the guarantors party thereto and U.S. Bank National Association, a national banking association, as Trustee and collateral agent (the "Senior Secured Notes Indenture") and issued $40.0 million aggregate principal amount of the Senior Secured Notes. In addition, in connection with the FDA's approval of ARYMO ER on January 9, 2017 and pursuant to the terms of the Senior Secured Notes Indenture, we issued an additional $40.0 million aggregate principal amount of the Senior Secured Notes on January 18, 2017. Our ability to make scheduled payments of the principal of, to pay interest on or to refinance our indebtedness and related obligations, including the Convertible Senior Notes and Senior Secured Notes, is subject to economic, financial, competitive and other factors beyond our control. We may be required to use a substantial portion of our cash flow from operations in the future to make debt service payments; alternatively, our business may not generate cash flow from operations in the future sufficient to service our debt and make necessary capital expenditures. If we are unable to generate such cash flow, we may be required to adopt one or more alternatives, such as selling assets, restructuring debt or obtaining additional equity capital on terms that may be onerous or highly dilutive. Our ability to refinance our indebtedness will depend on the capital markets and our financial condition at such time. We may not be able to engage in any of these activities or engage in these activities on desirable terms, which could result in a default on our debt obligations.

Our amended and restated certificate of incorporation designates the Court of Chancery of the State of Delaware as the sole and exclusive forum for certain types of actions and proceedings that may be initiated by our stockholders, which could limit our stockholders' ability to obtain a favorable judicial forum for disputes with us or our directors, officers or other employees.

        Our amended and restated certificate of incorporation provides that, with certain limited exceptions, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for any stockholder (including any beneficial owner) to bring (i) any derivative action or proceeding brought on our behalf, (ii) any action asserting a claim of breach of fiduciary duty owed by any director or officer of the Company owed to us or our stockholders, (iii) any action asserting a claim against us arising pursuant to any provision of the Delaware General Corporation Law or our certificate of incorporation or our bylaws, or (iv) any action asserting a claim against the Company governed by the internal affairs doctrine, in each case subject to the Court of Chancery having personal jurisdiction of the indispensable parties named as defendants. Any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock is deemed to have received notice of and consented to the foregoing provisions. This choice of

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forum provision may limit a stockholder's ability to bring a claim in a judicial forum that it finds favorable for disputes with us or our directors, officers or other employees, which may discourage such lawsuits against us and our directors, officers and employees. Alternatively, if a court were to find this choice of forum provision inapplicable to, or unenforceable in respect of, one or more of the specified types of actions or proceedings, we may incur additional costs associated with resolving such matters in other jurisdictions, which could adversely affect our business, financial condition or results of operations.

Changes in tax laws and regulations or in our operations may impact our effective tax rate and may adversely affect our business, financial condition and operating results.

        Changes in tax laws in any of the jurisdictions in which we operate, or adverse outcomes from tax audits that we may be subject to in any of the jurisdictions in which we operate, could result in an unfavorable change in our effective tax rate, which could adversely affect our business, financial condition and operating results.

        Additionally, we continue to assess the impact of various United States (the "U.S.") federal or state legislative proposals that could result in a material increase to our U.S. federal or state taxes. We cannot predict whether any specific legislation will be enacted or the terms of any such legislation. However, if such proposals were to be enacted, or if modifications were to be made to certain existing regulations, the consequences could have a material adverse impact on us, including increasing our tax burden, increasing the cost of tax compliance or otherwise adversely affecting our financial position, results of operations, cash flows and liquidity.

We may be limited in our ability to utilize, or may not be able to utilize, net operating loss carryforwards to reduce our future tax liability as a result of this offering.

        As disclosed in our most recent Annual Report on Form 10-K, under Section 382 of the Internal Revenue Code of 1986, as amended, if a corporation undergoes an "ownership change," generally defined as a greater than 50% change (by value) in its equity ownership over a three-year period, the corporation's ability to use its pre-change net operating losses ("NOLs") and other pre-change tax attributes (such as research tax credits) to offset its post-change income may be limited.

        This offering may, alone or in conjunction with other changes in our stock ownership that we cannot control, result in an ownership change for purposes of Section 382. If we undergo an ownership change, our ability to use our NOL carryforwards would become subject to certain limitations, although the extent of such limitations cannot presently be known. We may also experience ownership changes in the future as a result of subsequent changes in our stock ownership, which may be outside of our control. As a result, if we earn net taxable income, our ability to use our NOL carryforwards determined on the date of our ownership change to offset U.S. federal taxable income may be subject to limitations, which could potentially result in increased future tax liability to us.

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USE OF PROCEEDS

        We estimate that the net proceeds from the sale of the shares of common stock and accompanying warrants offered pursuant to this prospectus supplement, after deducting underwriting discounts and commissions and estimated offering expenses payable by us, will be approximately $28.6 million, or approximately $32.9 million if the underwriters exercise their option to purchase additional shares and warrants in full, based on the public offering price of $1.80 per share. The above does not give effect to any exercise of the warrants being offered and issued in the offering or the receipt of proceeds therefrom.

        We plan to use the net proceeds from this offering, together with our existing cash, cash equivalents and marketable securities available for sale, to provide additional resources for our commercial sales and marketing efforts with respect to ARYMO ER, (morphine sulfate) extended-release tablets for oral use—CII, SPRIX® (ketorolac tromethamine) Nasal Spray and OXAYDO® (oxycodone HCI, USP) tablets for oral use only—CII and for general corporate purposes, including potential business development opportunities. We may also use a portion of the net proceeds for the licensing or acquisition of complementary products, technologies or businesses. However, we have no present plans, agreements or commitments with respect to any potential acquisition, investment or license.

        As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses of the proceeds from this offering. The timing and amount of our actual expenditures will be based on many factors. Unless otherwise indicated in the prospectus supplement, our management will have broad discretion to allocate the net proceeds of the offerings and the occurrence of unforeseen events or changed business conditions could result in the application of the proceeds of the offering in a manner other than as described in this prospectus supplement. Pending their ultimate use, we intend to invest the net proceeds in short-term, investment-grade, interest-bearing instruments.

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CAPITALIZATION

        The following table sets forth our consolidated cash and capitalization as of March 31, 2017:

•

on an actual basis;



•

on a pro forma basis to give effect to the issuance and sale of 938,556 shares of our common stock by us pursuant to the 2015 Sales Agreement in the second quarter of 2017 at an average public offering price of $3.08 and the cancellation of 10,000 shares of restricted stock under the 2013 Plan in June 2017; and



•

on a pro forma as adjusted basis to give effect to the issuance and sale of 16,666,667 shares of our common stock by us and the receipt of the estimated net proceeds from such sale, at the public offering price of $1.80 per share and accompanying warrant (but excluding shares of common stock to be issued and any proceeds received upon exercise of the warrants), and after deducting underwriting discounts and commissions and estimated expenses payable by us.

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DILUTION

        If you invest in our common stock and accompanying warrants in this offering, your interest will be diluted immediately to the extent of the difference between the public offering price per share and accompanying warrant you will pay in this offering, and the as adjusted net tangible book value per share of our common stock and accompanying warrant after this offering. Our historical net tangible book value as of March 31, 2017, was $(25,035,000), or approximately $(0.99) per share, based on 25,407,427 shares of common stock outstanding as of such date. Net tangible book value per share is determined by dividing our total tangible assets, less total liabilities, by the number of shares of our common stock outstanding as of March 31, 2017.

        After giving effect to (i) the issuance and sale of 938,556 shares of our common stock by us pursuant to the 2015 Sales Agreement in the second quarter of 2017 at an average public offering price of $3.08 (the "Sales Agreement Shares"), (ii) the cancellation of 10,000 shares of restricted stock pursuant to the 2013 Plan in June 2017 and (iii) the issuance and sale of 16,666,667 shares of common stock and accompanying warrants by us at the public offering price of $1.80 per share and accompanying warrant (excluding shares of common stock to be issued and any proceeds received upon exercise of the warrants), after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of March 31, 2017 would have been approximately $6.4 million, or $0.15 per share. Assuming the completion of the offering, this represents an immediate increase in net tangible book value of $0.99 per share to existing stockholders and immediate dilution in net tangible book value of $1.65 per share to new investors participating in this offering at the public offering price. The following table illustrates this dilution on a per share basis:

        If the underwriter exercises in full its option to purchase up to 2,500,000 additional shares of common stock and accompanying warrants at the public offering price of $1.80 per share and accompanying warrant (excluding shares of common stock to be issued and any proceeds to be received upon exercise of the warrants), the as adjusted net tangible book value after this offering would be $0.23 per share, representing an increase in net tangible book value of $1.08 per share to existing stockholders and immediate dilution in net tangible book value of $1.57 per share to investors purchasing our common stock in this offering at the public offering price.

        To the extent that outstanding options or warrants are exercised, Convertible Notes are converted into common stock or we issue shares of common stock under our stock incentive plans, investors purchasing our common stock in this offering may experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

        The information does not give effect to the potential exercises of the warrants offered by the prospectus supplement. Investors that purchase common stock upon the exercise of the warrants offered hereby may experience dilution depending on our net tangible book value at the time of exercise.

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DESCRIPTION OF THE SECURITIES WE ARE OFFERING

        In this offering, we are offering 16,666,667 shares of common stock and warrants to purchase up to 16,666,667 shares of common stock. Each warrant will have an exercise price of $2.70 per share of common stock. No fractional warrants will be issued. The common stock and the warrants are immediately separable and will be issued separately. This prospectus supplement also relates to the offering of the shares of common stock issuable upon exercise of the offered warrants.

Common Stock

        The material terms and provisions of our common stock are described under the caption "Description of Capital Stock" starting on page 6 of the accompanying prospectus.

Warrants

        The material terms and provisions of the warrants being issued in this offering are summarized below. The following description is subject to, and qualified in its entirety by, the form of warrant and the warrant agreement between us and the warrant agent, each of which will be filed as an exhibit to a Current Report on Form 8-K to be filed by us with the SEC in connection with this offering. You should review the form of warrant and the warrant agreement for a complete description of the terms and conditions applicable to the warrants. See "Information Incorporated by Reference and Available Information" on page S-28.

        General.    Each purchaser of shares will receive a warrant to purchase a number of shares of common stock equal to the number of shares of common stock purchased by such investor in this offering.

        Exercisability.    The warrants may be exercised at any time on or after their date of issuance, will have an exercise price of $2.70 per share and are exercisable until the fifth year anniversary of the original issuance date. The warrants will be exercisable, at the option of each holder, in whole or in part by delivering to the warrant agent a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise. The exercise price of the warrant is subject to adjustment in the event of stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock.

        Exercise Limitations.    A holder of a warrant will not have the right to exercise any portion of the warrant if the holder (together with its affiliates) would beneficially own in excess of 4.99% of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the warrants. However, any holder may increase or decrease such percentage to any other percentage not in excess of 9.99% upon at least 61 days' prior notice from the holder to us.

        Transferability.    Subject to applicable laws, the warrants are separately tradeable immediately after issuance at the option of the holders and may be transferred at the option of the holders. The warrants will be issued in book-entry form under a warrant agreement between the warrant agent and us, and shall initially be represented by one or more book-entry certificates deposited with The Depository Trust Company, or DTC, and registered in the name of Cede & Co., a nominee of DTC, or as otherwise directed by DTC.

        No Listing.    There is no established public trading market for the warrants and we do not expect a market to develop. In addition, we do not intend to apply for listing of the warrants on any securities exchange or recognized trading system. Without an active market, the liquidity of the warrants will be limited.

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        Fundamental Transactions.    In the event of an "fundamental transaction," as defined in the warrant agreement and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common stock, the holders of the warrants will be entitled to receive upon exercise of the warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the warrants immediately prior to such fundamental transaction. In the event of a fundamental transaction of which we are not the surviving entity and certain other fundamental transactions, we or any successor entity will pay at the holder's option, exercisable at any time concurrently with or within 30 days after the consummation of the fundamental transaction, an amount of cash equal to the value of the warrant as determined in accordance with the Black Scholes option pricing model and the terms of the warrants.

        Anti-Dilution.    The warrants contain a price protection feature, to the extent such warrants have not been exercised previously, to adjust the exercise price if shares of common stock are sold or issued in the future for a consideration per share less than the exercise price per share then in effect, based on the number of shares then outstanding and the number of shares being issued in such offering.

        Cashless Exercise.    If, at the time a holder exercises its warrant, there is no effective registration statement registering, or the prospectus contained therein is not available for an issuance of the shares underlying the warrant to the holder, and the holder is not able to sell the shares issuable upon exercise of the warrant without limitations on volume pursuant to Rule 144, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net number of shares of our common stock determined according to a formula set forth in the warrant. In the event of a cashless exercise, if we fail to timely deliver the shares underlying the warrants, we will be subject to certain buy-in provisions.

        Variable Rate Transactions.    During the term of the warrant, we are prohibited from effecting or entering into any issuance of common stock or Common Stock Equivalents (as defined in the warrant agreement) involving a Variable Rate Transaction (as defined in the warrant agreement).

        Rights as a Stockholder.    Except as otherwise provided in the warrant or by virtue of a holder's ownership of shares of our common stock, the holders of the warrants do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise their warrants.

        Amendments.    Amendments and waivers of the terms of the warrants require the written consent of the holders of warrants representing not less than a majority of the shares issuable upon exercise of the warrants then outstanding and us, as well as any warrant holder that would be disproportionately and materially adversely impacted by the amendment.

        No Fractional Shares.    No fractional shares or scrip representing fractional shares shall be issued upon the exercise of the warrants. As to any fraction of a share which the holder would otherwise be entitled to purchase upon such exercise, we shall cause the warrant agent to, at our option, pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the exercise price of the warrant per whole share or round such fractional share up to the nearest whole share.

        Warrant Agent.    Our warrant agent is Broadridge Corporate Issuer Solutions, Inc.

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS

        The following is a general discussion of the material U.S. federal income considerations applicable to the ownership and disposition of shares of our common stock and warrants acquired in this offering. This discussion is for general information only and is not tax advice. Accordingly, all prospective holders of our common stock and warrants should consult their own tax advisors with respect to the U.S. federal, state, local and non-U.S. tax consequences of the purchase, ownership and disposition of our common stock and warrants. This discussion is based on current provisions of the U.S. Internal Revenue Code of 1986, as amended, which we refer to as the Code, existing and proposed U.S. Treasury Regulations promulgated thereunder, current administrative rulings and judicial decisions, all as in effect as of the date of this prospectus supplement, all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any change could alter the tax consequences described in this prospectus supplement. We assume in this discussion that each holder holds shares of our common stock and warrants as capital assets within the meaning of Section 1221 of the Code (generally property held for investment).

        This discussion does not address all aspects of U.S. federal income taxation that may be relevant to a particular holder in light of that holder's individual circumstances, does not address the alternative minimum or Medicare contribution taxes, and does not address any aspects of U.S. state, local or non-U.S. taxes or any U.S. federal taxes other than income tax. This discussion also does not consider any specific facts or circumstances that may apply to a non-U.S. holder and does not address aspects of U.S. federal income taxation that may be applicable to investors that are subject to special tax rules, including without limitation:

•

insurance companies;



•

tax-exempt organizations;



•

financial institutions;



•

brokers or dealers in securities;



•

regulated investment companies;



•

real estate investment trusts;



•

pension plans, individual retirement accounts and other tax deferred accounts;



•

persons that mark their securities to market;



•

controlled foreign corporations;



•

passive foreign investment companies;



•

"dual resident" corporations;



•

persons that receive our common stock or warrants as compensation for the performance of services;



•

owners that hold our common stock or warrants as part of a straddle, hedge, conversion transaction, synthetic security or other integrated investment;



•

owners that own, or are deemed to own, more than 5% of our capital stock (except to the extent specifically set forth below);



•

persons that have a functional currency other than the U.S. dollar; and



•

certain U.S. expatriates.

        In addition, this discussion does not address the tax treatment of partnerships or other pass-through entities for U.S. federal income tax purposes, or persons who hold our common stock or warrants through partnerships or other pass-through entities for U.S. federal income tax purposes. A partner in a partnership or other pass-through entity that will hold our common stock or warrants

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should consult his, her or its own tax advisor regarding the tax consequences of acquiring, holding and disposing of our common stock or warrants through a partnership or other pass-through entity, as applicable.

        There can be no assurance that the Internal Revenue Service, which we refer to as the IRS, will not challenge one or more of the tax consequences described herein. We have not obtained, nor do we intend to obtain, a ruling from the IRS with respect to the U.S. federal income tax consequences of the purchase, ownership or disposition of our common stock or warrants.

Allocation of Purchase Price Between Common Stock and Warrants to Purchase Our Common Stock

        Each share of common stock will be issued together with a warrant, and each holder of our common stock and warrants must allocate the purchase price paid by such holder for our common stock and a warrant between the share of common stock and the warrant based on the relative fair market value of each. This allocation will establish a holder's initial tax basis for U.S. federal income tax purposes in their shares of common stock and warrants. We will not be providing holders with such allocation, and it is possible that different holders will reach different determinations regarding such allocation. A holder's allocation of purchase price between common stock and warrants is not binding on the IRS or the courts, and no assurance can be given that the IRS or the courts will agree with a holder's allocation.

        Accordingly, each prospective holder should consult their own tax advisor with respect to the risks associated with an allocation of the purchase price between our common stock and the warrants.

U.S. Holders

        This section applies to you if you are a "U.S. holder." For purposes of this discussion, a "U.S. holder" means a beneficial owner of our common stock and warrants who is for U.S. federal income tax purposes: (i) an individual who is a citizen or resident of the United States; (ii) a corporation, or any other organization taxable as a corporation for U.S. federal income tax purposes, created or organized in the United States or under the laws of the United States or of any state thereof or the District of Columbia; (iii) an estate, the income of which is subject to U.S. federal income tax regardless of its source; or (iv) a trust if (1) a U.S. court is able to exercise primary supervision over the trust's administration and one or more U.S. persons have the authority to control all of the trust's substantial decisions or (2) the trust has a valid election in effect under applicable U.S. Treasury Regulations to be treated as a U.S. person.

Distributions on Our Common Stock and Warrants

        Distributions, if any, on our common stock generally will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits as determined under U.S. federal income tax principles. If a distribution exceeds our current and accumulated earnings and profits, the excess will be treated as a tax-free return of the U.S. holder's investment, up to such U.S. holder's tax basis in the common stock. Any remaining excess will be treated as capital gain, subject to the tax treatment described below in "—Gain on Sale, Exchange or Other Taxable Disposition of Our Common Stock." Dividends paid by us will generally be eligible for the reduced rates of tax for qualified dividend income allowed to individual U.S. holders and for the dividends received deduction allowed to corporate U.S. holders, in each case assuming that certain holding period and other requirements are satisfied.

        While it is not free from doubt, we expect that cash distributions paid on the warrants, on an "as-converted" basis, if any, are subject to the same tax consequences as described in the preceding paragraph for the common stock; however, distributions received in respect of a warrant may not qualify for the lower tax rates applicable to qualified dividend income. U.S. holders should consult their own tax advisors regarding the proper treatment of any distributions paid on the warrants.

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Conversion of Warrants into Our Common Stock

        Except as discussed below with respect to the cashless exercise of a warrant, a U.S. holder will not recognize gain or loss on the conversion of warrants into our common stock. A U.S. holder's tax basis in the common stock received upon a conversion will equal the sum of (i) the initial tax basis of the warrants converted and (ii) price paid upon exercise. The U.S. holder's holding period for the common stock received upon exercise of the warrants will begin on the date following the date of exercise of the warrants and will not include the period during which the U.S. holder held the warrants.

        The tax consequences of a cashless exercise of a warrant are not clear under current U.S. tax law. A cashless exercise may be tax-free, either because the exercise is not a realization event or because the exercise is treated as a recapitalization for U.S. federal income tax purposes. In this case, a U.S. holder's basis in the common stock received would equal the U.S. holder's basis in the warrant. If the cashless exercise were treated as a recapitalization, the holding period of the common stock would include the holding period of the warrant.

        It is possible that a cashless exercise could be treated in part as a taxable exchange in which gain or loss would be recognized with respect to the warrants surrendered to pay the exercise price for warrants converted into common stock. In that event, a U.S. holder could be deemed to have surrendered only those warrants used to satisfy the exercise price for an amount equal to the aggregate fair market value of the exercise price of the total number of warrants to be exercised. The U.S. holder would recognize capital gain or loss in an amount equal to the difference between the amount deemed realized and the U.S. holder's tax basis in the warrants surrendered to pay the exercise price. In this case, a U.S. holder's tax basis in the common stock received would equal the sum of the U.S. holder's initial investment in the converted warrants (i.e., the portion of the U.S. holder's purchase price for the shares of common stock that is allocated to the warrants, as described above under "—Allocation of Purchase Price between Common Stock and Warrants") and the exercise price of the warrants converted. A U.S. holder's holding period for the common stock would commence on the date following the date of exercise.

        Due to the absence of authority on the U.S. federal income tax treatment of a cashless exercise, there can be no assurance which, if any, of the alternative tax consequences and holding periods described above would be adopted by the IRS or a court of law. Accordingly, U.S. holders should consult their own tax advisors regarding the tax consequences of a cashless exercise.

        If a warrant is allowed to lapse unexercised, a U.S. holder generally will recognize a capital loss equal to such holder's tax basis in the warrant.

Sale, Exchange or Other Taxable Disposition of Our Common Stock or Warrants

        Upon the sale, exchange, or other taxable disposition of our common stock or warrants, a U.S. holder will recognize gain or loss equal to the difference between the amount realized upon the disposition and the U.S. holder's tax basis in the common stock or warrants sold or exchanged. Any gain or loss generally will be capital gain or loss, and will be long-term capital gain or loss if the U.S. holder's holding period for the common stock or warrants exceeded one year at the time of the disposition. Certain U.S. holders (including individuals) are currently eligible for preferential rates of U.S. federal income taxation in respect of long-term capital gains. The deductibility of capital losses is subject to significant limitations.

Information Reporting and Backup Withholding

        In general, information reporting requirements may apply to dividends paid to a U.S. holder on our common stock or the warrants, and to the proceeds of the sale, exchange or other disposition of our common stock and warrants, unless the U.S. holder is an exempt recipient. Backup withholding may apply to such payments if the U.S. holder fails to provide a taxpayer identification number, a certification of exempt status or has been notified by the IRS that it is subject to backup withholding

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(and such notification has not been withdrawn). Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules will be allowed as a refund or a credit against a U.S. holder's U.S. federal income tax liability provided the required information is timely furnished to the IRS.

Non-U.S. Holders

        This section applies to you if you are a "non-U.S. holder". For purposes of this discussion, a "non-U.S. holder" means a person who is not a U.S. holder (as defined above under "U.S. Holders").

Distributions on Our Common Stock and Warrants

        Distributions, if any, on our common stock generally will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. If a distribution exceeds our current and accumulated earnings and profits, the excess will be treated as a tax-free return of the non-U.S. holder's investment, up to such non-U.S. holder's tax basis in the common stock. Any remaining excess will be treated as capital gain, subject to the tax treatment described below in "Gain on Sale, Exchange or Other Taxable Disposition of Our Common Stock."

        While it is not free from doubt, we expect that cash distributions paid on the warrants, on an "as-converted" basis, if any, are subject to the same tax consequences as described in the preceding paragraph for the common stock. Non-U.S. Holders should consult their own tax advisors regarding the proper treatment of any distributions paid on the warrants.

        Subject to the discussions below regarding backup withholding and the Foreign Account Tax Compliance Act, or FATCA, dividends paid to a non-U.S. holder generally will be subject to withholding of U.S. federal income tax at a rate of 30% of the gross amount or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence, unless such dividends are effectively connected with a trade or business conducted by a non U.S. holder within the U.S (as discussed below). A non-U.S. holder of our common stock or warrants who claims the benefit of an applicable income tax treaty between the United States and such holder's country of residence generally will be required to provide a properly executed IRS Form W-8BEN or W-8BEN-E (or successor form), as applicable, and satisfy applicable certification and other requirements. Non-U.S. holders are urged to consult their own tax advisors regarding their entitlement to benefits under a relevant income tax treaty. A non-U.S. holder that is eligible for a reduced rate of U.S. withholding tax under an income tax treaty may be able to obtain a refund or credit of any excess amounts withheld by timely filing the required information with the IRS.

        Subject to the discussions below regarding backup withholding and FATCA, dividends that are treated as effectively connected with a trade or business conducted by a non-U.S. holder within the United States and, if an applicable income tax treaty so provides, that are attributable to a "permanent establishment" or a "fixed base" maintained by the non-U.S. holder within the United States, are generally exempt from the 30% withholding tax if the non-U.S. holder satisfies applicable certification and disclosure requirements. U.S. effectively connected income, net of specified deductions and credits, is generally taxed at the same graduated U.S. federal income tax rates applicable to United States persons (as defined in the Code). Any U.S. effectively connected income received by a non-U.S. holder that is a corporation may also be subject to an additional "branch profits tax" at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence.

Conversion of Warrants into Our Common Stock

        The U.S. federal income tax treatment of a non-U.S. holder's exercise of a warrant, or the lapse of a warrant held by a Non-U.S. Holder, generally will correspond to the U.S. federal income tax

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treatment of the exercise or lapse of a warrant by a U.S. Holder, as described under "U.S. Holders—Conversion of Warrants into Common Stock" above.

Gain on Sale, Exchange or Other Taxable Disposition of Our Common Stock or Warrants

        Subject to the discussions below regarding backup withholding and FATCA, in general, a non-U.S. holder will not be subject to any U.S. federal income tax on any gain realized upon such holder's sale, exchange or other taxable disposition of shares of our common stock or warrants unless:

•

the gain is effectively connected with the non-U.S. holder's conduct of a U.S. trade or business and, if an applicable income tax treaty so provides, is attributable to a "permanent establishment" or a "fixed base" maintained by such non-U.S. holder in the United States, in which case the non-U.S. holder generally will be taxed on such gain at the graduated U.S. federal income tax rates applicable to United States persons (as defined in the Code) and, if the non-U.S. holder is a foreign corporation, the branch profits tax described above in "Distributions on Our Common Stock" also may apply to such gain;



•

the non-U.S. holder is a nonresident alien individual who is present in the United States for 183 days or more in the taxable year of the taxable disposition and certain other conditions are met, in which case the non-U.S. holder will be subject to a 30% tax (or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence) on the net gain derived from the taxable disposition, which may be offset by certain U.S. source capital losses of the non-U.S. holder, if any; or



•

we are, or have been, at any time during the five-year period preceding such taxable disposition (or the non-U.S. holder's holding period, if shorter) a "U.S. real property holding corporation," unless our common stock is regularly traded on an established securities market and the non-U.S. holder holds no more than 5% of our outstanding common stock, directly or indirectly, during the shorter of the 5-year period ending on the date of the taxable disposition or the period that the non-U.S. holder held our common stock. If we are determined to be a U.S. real property holding corporation and the foregoing exception does not apply, then a purchaser may withhold 15% of the proceeds payable to a non-U.S. holder from a sale of our common stock or warrants, and the non-U.S. holder generally will be taxed on its net gain derived from the disposition at the graduated U.S. federal income tax rates applicable to United States persons (as defined in the Code). Generally, a corporation is a U.S. real property holding corporation only if the fair market value of its U.S. real property interests equals or exceeds 50% of the sum of the fair market value of its worldwide real property interests plus its other assets used or held for use in a trade or business. Although there can be no assurance, we do not believe that we are, or have been, a U.S. real property holding corporation, or that we are likely to become one in the future. No assurance can be provided that our common stock will be regularly traded on an established securities market for purposes of the rules described above.

Backup Withholding and Information Reporting

        We must report annually to the IRS and to each non-U.S. holder the gross amount of the distributions paid on our common stock or warrants to such holder and the tax withheld, if any, with respect to such distributions. Non-U.S. holders may have to comply with specific certification procedures to establish that the holder is not a United States person (as defined in the Code) in order to avoid backup withholding at the applicable rate with respect to dividends on our common stock or warrants. Dividends paid to non-U.S. holders subject to the U.S. withholding tax, as described above in "Distributions on Our Common Stock and Warrants," generally will be exempt from U.S. backup withholding.

        Information reporting and backup withholding generally will apply to the proceeds of a disposition of our common stock and warrants by a non-U.S. holder effected by or through the U.S. office of any

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broker, U.S. or foreign, unless the holder certifies its status as a non-U.S. holder and satisfies certain other requirements, or otherwise establishes an exemption. Generally, information reporting and backup withholding will not apply to a payment of disposition proceeds to a non-U.S. holder where the transaction is effected outside the United States through a non-U.S. office of a broker. However, for information reporting purposes, dispositions effected through a non-U.S. office of a broker with substantial U.S. ownership or operations generally will be treated in a manner similar to dispositions effected through a U.S. office of a broker. Non-U.S. holders should consult their own tax advisors regarding the application of the information reporting and backup withholding rules to them.

        Copies of information returns may be made available to the tax authorities of the country in which the non-U.S. holder resides or is incorporated under the provisions of a specific treaty or agreement.

        Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder can be refunded or credited against the non-U.S. holder's U.S. federal income tax liability, if any, provided that an appropriate claim is filed with the IRS.

Withholding and Information Reporting Requirements—FATCA

        FATCA may impose a U.S. federal withholding tax at a rate of 30% on payments of dividends on, or gross proceeds from the sale or other disposition of, our common stock or warrants paid to certain foreign entities, unless (i) if the foreign entity is a "foreign financial institution," such foreign entity undertakes certain due diligence, reporting, withholding, and certification obligations, (ii) if the foreign entity is not a "foreign financial institution," such foreign entity either certifies that it does not have any "substantial United States owners" (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (iii) the foreign entity otherwise qualifies from an exemption these rules. Under applicable U.S. Treasury Regulations, withholding under FATCA currently applies to payments of dividends paid on our common stock or deemed paid on the warrants and is scheduled to apply to gross proceeds from a sale or other disposition of our common stock or warrants made on or after January 1, 2019. A Non-U.S. holder that is not subject to FATCA withholding generally may certify its exempt status by furnishing a properly executed IRS Form W-8BEN or Form W-8BEN-E (or successor form), as applicable. Under certain circumstances, a non-U.S. holder may be eligible for refunds or credits of the tax. Certain intergovernmental agreements between the United States and other countries may modify these rules. Non-U.S. holders should consult their own tax advisors regarding the possible implications of this legislation on their investment in our common stock and the entities through which they hold our common stock, including, without limitation, the process and deadlines for meeting the applicable requirements to prevent the imposition of the 30% withholding tax under FATCA.

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UNDERWRITING

        Subject to the terms and conditions set forth in the underwriting agreement, dated July 6, 2017, between us and Cantor Fitzgerald & Co., as the sole book-running manager of this offering, we have agreed to sell to Cantor, and Cantor has agreed to purchase from us, the shares of common stock and accompanying warrants offered by this prospectus.

        The underwriting agreement provides that the obligations of Cantor are subject to certain conditions precedent such as the receipt by Cantor of officers' certificates and legal opinions and approval of certain legal matters by its counsel. The underwriting agreement provides that Cantor will purchase all of the shares of common stock and accompanying warrants if any of them are purchased. We have agreed to indemnify Cantor and certain of its controlling persons against certain liabilities, including liabilities under the Securities Act, and to contribute to payments that Cantor may be required to make in respect of those liabilities.

        Cantor is offering the shares of common stock and accompanying warrants, subject to prior sale, when, as and if issued to and accepted by it, subject to approval of legal matters by its counsel and other conditions specified in the underwriting agreement. Cantor reserves the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

Option to Purchase Additional Shares and Warrants

        We have granted to Cantor an option, exercisable for 30 days from the date of this prospectus supplement, to purchase, from time to time, in whole or in part, up to an aggregate of 2,500,000 shares of common stock and accompanying warrants from us at the public offering price set forth on the cover page of this prospectus supplement, less underwriting discounts and commissions.

Commission and Expenses

        Cantor has advised us that it proposes to offer the shares of common stock and accompanying warrants to the public at the public offering price set forth on the cover page of this prospectus supplement and to certain dealers, which may include the underwriters, at that price less a concession not in excess of $0.0432 per share of common stock and accompanying warrants. After the offering, Cantor may change the offering price and other selling terms.

        The following table shows the public offering price, the underwriting discounts and commissions that we are to pay Cantor and the proceeds, before expenses, to us in connection with this offering. Such amounts are shown assuming both no exercise and full exercise of Cantor's option to purchase additional shares and warrants.

        We estimate expenses payable by us in connection with this offering, other than the underwriting discounts and commissions referred to above, will be approximately $200,000. We have also agreed to

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reimburse the underwriters for up to $15,000 for their FINRA counsel's fees and expenses, which reimbursed fee is deemed underwriting compensation for this offering by FINRA.

Listing

        Our common stock is listed on The NASDAQ Global Market under the trading symbol "EGLT." There is no established public trading market for the warrants and we do not expect a market to develop. In addition, we do not intend to apply for listing of the warrants on any securities exchange or recognized trading system. The warrants will be issued in book-entry form pursuant to a warrant agreement between us and Broadridge Corporate Issuer Solutions, Inc., as warrant agent.

No Sales of Similar Securities

        We, our officers and our directors have agreed, subject to certain specified exceptions, not to directly or indirectly, for a period of 90 days after the date of the underwriting agreement:

•

sell, offer, contract or grant any option to sell (including any short sale), pledge, transfer, establish an open "put equivalent position" within the meaning of Rule 16a-l(h) under the Securities Exchange Act of 1934, as amended, or otherwise dispose of, any shares of common stock, options or warrants to acquire shares of common stock, or securities exchangeable or exercisable for or convertible into shares of common stock currently or hereafter owned either of record or beneficially;



•

enter into any swap, hedge or other agreement or transaction that transfers, in whole or in part, the economic consequence of ownership of common stock, or securities exchangeable or exercisable for or convertible into shares of common stock; or



•

publicly announce an intention to do any of the foregoing for a period of 90 days after the date of this prospectus supplement without the prior written consent of Cantor.

        In addition, we and each such person agrees that, without the prior written consent of Cantor, we or such other person will not, during the restricted period, make any demand for, or exercise any right with respect to, the registration of any shares of common stock or any security convertible into or exercisable or exchangeable for common stock.

        Cantor may, in its sole discretion and at any time or from time to time before the termination of the 90-day period release all or any portion of the securities subject to lock-up agreements.

Stabilization

        The underwriter has advised us that it, pursuant to Regulation M under the Securities Exchange Act of 1934, as amended, may engage in short sale transactions, stabilizing transactions, syndicate covering transactions or the imposition of penalty bids in connection with this offering. These activities may have the effect of stabilizing or maintaining the market price of the common stock at a level above that which might otherwise prevail in the open market. Establishing short sales positions may involve either "covered" short sales or "naked" short sales.

        "Covered" short sales are sales made in an amount not greater than the underwriter's option to purchase additional shares of our common stock in this offering. The underwriter may close out any covered short position by either exercising its option to purchase additional shares of our common stock or purchasing shares of our common stock in the open market. In determining the source of shares to close out the covered short position, the underwriter will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which it may purchase shares through the option to purchase additional shares.

        "Naked" short sales are sales in excess of the option to purchase additional shares of our common stock. The underwriter must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriter is concerned that there

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may be downward pressure on the price of the shares of our common stock in the open market after pricing that could adversely affect investors who purchase in this offering.

        A stabilizing bid is a bid for the purchase of shares of common stock on behalf of the underwriter for the purpose of fixing or maintaining the price of the common stock. A syndicate covering transaction is the bid for or the purchase of shares of common stock on behalf of the underwriter to reduce a short position incurred by the underwriter in connection with the offering. Similar to other purchase transactions, the underwriter's purchases to cover the syndicate short sales may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock may be higher than the price that might otherwise exist in the open market. A penalty bid is an arrangement permitting the underwriter to reclaim the selling concession otherwise accruing to a syndicate member in connection with the offering if the common stock originally sold by such syndicate member are purchased in a syndicate covering transaction and therefore have not been effectively placed by such syndicate member.

        Neither we nor the underwriter make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common stock. The underwriter is not obligated to engage in these activities and, if commenced, may end any of these activities at any time.

Passive Market Making

        The underwriter may also engage in passive market making transactions in our common stock on the NASDAQ in accordance with Rule 103 of Regulation M during a period before the commencement of offers or sales of shares of our common stock in this offering and extending through the completion of distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker's bid, that bid must then be lowered when specified purchase limits are exceeded. Passive market making may cause the price of our common stock to be higher than the price that otherwise would exist in the open market in the absence of those transactions. The underwriter is not required to engage in passive market making and, if commenced, may end passive market making activities at any time.

Electronic Distribution

        A prospectus in electronic format may be made available by e-mail or on the web sites or through online services maintained by one or more of the underwriters, selling group members (if any) or their affiliates. The underwriter may agree with us to allocate a specific number of securities for sale to online brokerage account holders. Any such allocation for online distributions will be made by the underwriter on the same basis as other allocations. Other than the prospectus in electronic format, the information on the underwriter's web site and any information contained in any other web site maintained by the underwriter is not part of this prospectus supplement, has not been approved and/or endorsed by us or the underwriter and should not be relied upon by investors.

Other Activities and Relationships

        Cantor and certain of its affiliates are full service financial institutions engaged in a wide range of activities for their own accounts and the accounts of customers, which may include, among other things, corporate finance, mergers and acquisitions, merchant banking, equity and fixed income sales, trading and research, derivatives, foreign exchange, futures, asset management, custody, clearance and securities lending. Cantor and certain of its affiliates have, from time to time, performed, and may in the future perform, various investment banking and financial advisory services for us and our affiliates, for which it received or will receive customary fees and expenses.

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        In addition, in the ordinary course of its business, Cantor and its affiliates may, directly or indirectly, hold long or short positions, trade and otherwise conduct such activities in or with respect to debt or equity securities and/or bank debt of, and/or derivative products. Such investment and securities activities may involve our securities and instruments. Cantor and its affiliates may also make investment recommendations or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long or short positions in such securities and instruments.

        Cantor is the sales agent under our 2015 Sales Agreement, accordingly Cantor has received and may receive customary fees and commissions for these transactions.

Stamp Taxes

        If you purchase securities offered in this prospectus supplement, you may be required to pay stamp taxes and other charges under the laws and practices of the country of purchase, in addition to the offering price listed on the cover page of this prospectus supplement.

Notice to Investors

Canada

        This prospectus supplement constitutes an "exempt offering document" as defined in and for the purposes of applicable Canadian securities laws. No prospectus has been filed with any securities commission or similar regulatory authority in Canada in connection with the offer and sale of the securities. No securities commission or similar regulatory authority in Canada has reviewed or in any way passed upon this prospectus supplement or on the merits of the securities and any representation to the contrary is an offence.

        Canadian investors are advised that this prospectus supplement has been prepared in reliance on section 3A.3 of National Instrument 33-105 Underwriting Conflicts ("NI 33-105"). Pursuant to section 3A.3 of NI 33-105, this prospectus supplement is exempt from the requirement that the Company and the underwriter(s) provide investors with certain conflicts of interest disclosure pertaining to "connected issuer" and/or "related issuer" relationships that may exist between the Company and the underwriter(s) as would otherwise be required pursuant to subsection 2.1(1) of NI 33-105.

Resale Restrictions

        The offer and sale of the securities in Canada is being made on a private placement basis only and is exempt from the requirement that the Company prepares and files a prospectus under applicable Canadian securities laws. Any resale of the securities acquired by a Canadian investor in this offering must be made in accordance with applicable Canadian securities laws, which may vary depending on the relevant jurisdiction, and which may require resales to be made in accordance with Canadian prospectus requirements, pursuant to a statutory exemption from the prospectus requirements, in a transaction exempt from the prospectus requirements or otherwise under a discretionary exemption from the prospectus requirements granted by the applicable local Canadian securities regulatory authority. These resale restrictions may under certain circumstances apply to resales of the securities outside of Canada.

Representations of Purchasers

        Each Canadian investor who purchases the securities will be deemed to have represented to the Company and the underwriter(s) that the investor (i) is purchasing the securities as principal, or is deemed to be purchasing as principal in accordance with applicable Canadian securities laws, for investment only and not with a view to resale or redistribution; (ii) is an "accredited investor" as such term is defined in section 1.1 of National Instrument 45-106 Prospectus Exemptions ("NI 45-106") or, in

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Ontario, as such term is defined in section 73.3(1) of the Securities Act (Ontario); and (iii) is a "permitted client" as such term is defined in section 1.1 of National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations.

Taxation and Eligibility for Investment

        Any discussion of taxation and related matters contained in this prospectus supplement does not purport to be a comprehensive description of all of the tax considerations that may be relevant to a Canadian investor when deciding to purchase the securities and, in particular, does not address any Canadian tax considerations. No representation or warranty is hereby made as to the tax consequences to a resident, or deemed resident, of Canada of an investment in the securities or with respect to the eligibility of the securities for investment by such investor under relevant Canadian federal and provincial legislation and regulations.

Rights of Action for Damages or Rescission

        Securities legislation in certain of the Canadian jurisdictions provides certain purchasers of securities pursuant to an offering memorandum (such as this prospectus supplement), including where the distribution involves an "eligible foreign security" as such term is defined in Ontario Securities Commission Rule 45-501 Ontario Prospectus and Registration Exemptions and in Multilateral Instrument 45-107 Listing Representation and Statutory Rights of Action Disclosure Exemptions, as applicable, with a remedy for damages or rescission, or both, in addition to any other rights they may have at law, where the offering memorandum, or other offering document that constitutes an offering memorandum, and any amendment thereto, contains a "misrepresentation" as defined under applicable Canadian securities laws. These remedies, or notice with respect to these remedies, must be exercised or delivered, as the case may be, by the purchaser within the time limits prescribed under, and are subject to limitations and defences under, applicable Canadian securities legislation. In addition, these remedies are in addition to and without derogation from any other right or remedy available at law to the investor.

Language of Documents

        Upon receipt of this document, each Canadian investor hereby confirms that it has expressly requested that all documents evidencing or relating in any way to the sale of the securities described herein (including for greater certainty any purchase confirmation or any notice) be drawn up in the English language only. Par la réception de ce document, chaque investisseur Canadien confirme par les présentes qu'il a expressément exigé que tous les documents faisant foi ou se rapportant de quelque manière que ce soit à la vente des valeurs mobilières décrites aux présentes (incluant, pour plus de certitude, toute confirmation d'achat ou tout avis) soient rédigés en anglais seulement.

Australia

        This prospectus is not a disclosure document for the purposes of Australia's Corporations Act 2001 (Cth) of Australia, or Corporations Act, has not been lodged with the Australian Securities & Investments Commission and is only directed to the categories of exempt persons set out below. Accordingly, if you receive this prospectus in Australia:

        You confirm and warrant that you are either:

•

a "sophisticated investor" under section 708(8)(a) or (b) of the Corporations Act;



•

a "sophisticated investor" under section 708(8)(c) or (d) of the Corporations Act and that you have provided an accountant's certificate to the company which complies with the requirements of section 708(8)(c)(i) or (ii) of the Corporations Act and related regulations before the offer has been made; or



•

a "professional investor" within the meaning of section 708(11)(a) or (b) of the Corporations Act.

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        To the extent that you are unable to confirm or warrant that you are an exempt sophisticated investor or professional investor under the Corporations Act any offer made to you under this prospectus is void and incapable of acceptance.

        You warrant and agree that you will not offer any of the securities issued to you pursuant to this prospectus for resale in Australia within 12 months of those securities being issued unless any such resale offer is exempt from the requirement to issue a disclosure document under section 708 of the Corporations Act.

European Economic Area

        In relation to each member state of the European Economic Area which has implemented the Prospectus Directive, each referred to herein as a Relevant Member State, with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State, referred to herein as the Relevant Implementation Date, no offer of any securities which are the subject of the offering contemplated by this prospectus has been or will be made to the public in that Relevant Member State other than any offer where a prospectus has been or will be published in relation to such securities that has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the relevant competent authority in that Relevant Member State in accordance with the Prospectus Directive, except that with effect from and including the Relevant Implementation Date, an offer of such securities may be made to the public in that Relevant Member State:

•

to any legal entity which is a "qualified investor" as defined in the Prospectus Directive;



•

to fewer than 100 or, if the Relevant Member State has implemented the relevant provision of the 2010 PD Amending Directive, 150, natural or legal persons (other than qualified investors as defined in the Prospectus Directive), as permitted under the Prospectus Directive, subject to obtaining the prior consent of the representatives of the underwriters for any such offer; or



•

in any other circumstances falling within Article 3(2) of the Prospectus Directive,

provided that no such offer of securities shall require the Company or any of the underwriters to publish a prospectus pursuant to Article 3 of the Prospectus Directive or supplement a prospectus pursuant to Article 16 of the Prospectus Directive.

        For the purposes of this provision, the expression an "offer to the public" in relation to any securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to purchase or subscribe the securities, as the same may be varied in that Relevant Member State by any measure implementing the Prospectus Directive in that Relevant Member State and the expression "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in the Relevant Member State and the expression "2010 PD Amending Directive" means Directive 2010/73/EU.

Hong Kong

        No securities have been offered or sold, and no securities may be offered or sold, in Hong Kong, by means of any document, other than to persons whose ordinary business is to buy or sell shares or debentures, whether as principal or agent; or to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or in other circumstances which do not result in the document being a "prospectus" as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32) of Hong Kong. No document, invitation or

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advertisement relating to the securities has been issued or may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted under the securities laws of Hong Kong) other than with respect to securities which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance.

        This prospectus has not been registered with the Registrar of Companies in Hong Kong. Accordingly, this prospectus may not be issued, circulated or distributed in Hong Kong, and the securities may not be offered for subscription to members of the public in Hong Kong. Each person acquiring the securities will be required, and is deemed by the acquisition of the securities, to confirm that he is aware of the restriction on offers of the securities described in this prospectus and the relevant offering documents and that he is not acquiring, and has not been offered any securities in circumstances that contravene any such restrictions.

Japan

        The offering has not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948 of Japan, as amended), or FIEL, and the Initial Purchaser will not offer or sell any securities, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means, unless otherwise provided herein, any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIEL and any other applicable laws, regulations and ministerial guidelines of Japan.

Singapore

        This prospectus has not been and will not be lodged or registered with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or the invitation for subscription or purchase of the securities may not be issued, circulated or distributed, nor may the securities be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to the public or any member of the public in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore, or the SFA, (ii) to a relevant person as defined under Section 275(2), or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions, specified in Section 275 of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of any other applicable provision of the SFA.

        Where the securities are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

•

a corporation (which is not an accredited investor as defined under Section 4A of the SFA) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or



•

a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary is an accredited investor,

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shares, debentures and units of shares and debentures of that corporation or the beneficiaries' rights and interest in that trust shall not be transferable for six months after that corporation or that trust has acquired the Offer Shares under Section 275 of the SFA except:

•

to an institutional investor under Section 274 of the SFA or to a relevant person defined in Section 275(2) of the SFA, or to any person pursuant to an offer that is made on terms that such shares, debentures and units of shares and debentures of that corporation or such rights and interest in that trust are acquired at a consideration of not less than $200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, and further for corporations, in accordance with the conditions, specified in Section 275 of the SFA;



•

where no consideration is given for the transfer; or



•

where the transfer is by operation of law.

Switzerland

        The securities may not be publicly offered in Switzerland and will not be listed on the SIX Swiss Exchange, or SIX, or on any other stock exchange or regulated trading facility in Switzerland. This prospectus has been prepared without regard to the disclosure standards for issuance prospectuses under art. 652a or art. 1156 of the Swiss Code of Obligations or the disclosure standards for listing prospectuses under art. 27 ff. of the SIX Listing Rules or the listing rules of any other stock exchange or regulated trading facility in Switzerland. Neither this prospectus nor any other offering or marketing material relating to the securities or the offering may be publicly distributed or otherwise made publicly available in Switzerland.

        Neither this prospectus nor any other offering or marketing material relating to the offering, the Company or the securities have been or will be filed with or approved by any Swiss regulatory authority. In particular, this prospectus will not be filed with, and the offer of securities will not be supervised by, the Swiss Financial Market Supervisory Authority FINMA, or FINMA, and the offer of securities has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes, or CISA. The investor protection afforded to acquirers of interests in collective investment schemes under the CISA does not extend to acquirers of securities.

Israel

        This document does not constitute a prospectus under the Israeli Securities Law, 5728-1968, or the Securities Law, and has not been filed with or approved by the Israel Securities Authority. In the State of Israel, this document is being distributed only to, and is directed only at, and any offer of the shares is directed only at, investors listed in the first addendum, or the Addendum, to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and "qualified individuals", each as defined in the Addendum (as it may be amended from time to time), collectively referred to as qualified investors (in each case purchasing for their own account or, where permitted under the Addendum, for the accounts of their clients who are investors listed in the Addendum). Qualified investors will be required to submit written confirmation that they fall within the scope of the Addendum, are aware of the meaning of same and agree to it.

United Kingdom

        This prospectus is only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors (as defined in the Prospectus Directive) that are also

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(i) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, referred to herein as the Order, and/or (ii) high net worth entities falling within Article 49(2)(a) to (d) of the Order and other persons to whom it may lawfully be communicated. Each such person is referred to herein as a Relevant Person.

        This prospectus and its contents are confidential and should not be distributed, published or reproduced (in whole or in part) or disclosed by recipients to any other persons in the United Kingdom. Any person in the United Kingdom that is not a Relevant Person should not act or rely on this document or any of its contents.

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LEGAL MATTERS

        The validity of the securities offered by this prospectus will be passed upon for Egalet Corporation by Dechert LLP, New York, New York. Certain legal matters will be passed upon for the underwriters by Cooley LLP, New York, New York.

EXPERTS

        Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2016, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in this registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young's report, given on their authority as experts in accounting and auditing.

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INFORMATION INCORPORATED BY REFERENCE AND AVAILABLE INFORMATION

        The SEC allows us to "incorporate by reference" into this prospectus the information contained in documents that we file with them, which means that we can disclose important information to you by referring you to those documents. Any information incorporated by reference is considered to be part of this prospectus. In the event of any conflict between any information in this prospectus and information incorporated by reference that we filed with the SEC before the date of this prospectus, the information in this prospectus shall supersede such other information, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we will make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), prior to the termination or completion of the offering of securities under this prospectus. Notwithstanding the foregoing, unless specifically stated to the contrary, none of the information that is not deemed "filed" with the SEC, including information furnished under Items 2.02 or 7.01 of any Current Report on Form 8-K, will be incorporated by reference into, or otherwise included in, this prospectus:

1.

our Annual Report on Form 10-K for the fiscal year ended December 31, 2016, filed with the SEC on March 13, 2017;



2.

our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2017 filed with the SEC on May 10, 2017;



3.

the description of our common stock contained in our Registration Statement on Form 8-A, filed with the SEC on February 3, 2014 pursuant to Section 12(b) of the Exchange Act; and



4.

our Current Reports on Form 8-K, originally filed with the SEC (only with respect to information included or incorporated into Item 8.01 thereof) on January 9, 2017, January 18, 2017, March 6, 2017, March 29, 2017, April 10, 2017, June 6, 2017 and June 13, 2017, June 20, 2017, July 5, 2017 and July 6, 2017.

        This prospectus supplement is part of a registration statement that we filed with the SEC. The registration statement contains more information than this prospectus supplement and the accompanying prospectus regarding us and the securities, including certain exhibits and schedules. Whenever a reference is made in this prospectus supplement and the accompanying prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated herein by reference for a copy of such contract, agreement or other document. We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. You may also read and copy any document we file at the SEC's Public Reference Room, 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room.

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        We make available, free of charge, through our website our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. You may also obtain, free of charge, a copy of any of these documents (other than exhibits to these documents unless the exhibits are specifically incorporated by reference into these documents or referred to in this prospectus) by writing or calling us at the following address and telephone number:

Egalet Corporation
600 Lee Road
Suite 100
Wayne, PA 19087
(610) 833-4200

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PROSPECTUS

$150,000,000

EGALET CORPORATION

Common Stock
Preferred Stock
Warrants
Debt Securities
Rights to Purchase Common Stock, Preferred Stock,
Debt Securities or Units
Units

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        We may offer and sell from time to time our shares of common stock, shares of preferred stock, warrants, debt securities and rights to purchase common stock, preferred stock, debt securities or units, as well as units that include any of these securities. We may sell any combination of these securities in one or more offerings with an aggregate initial offering price of up to $150,000,000.

        This prospectus provides you with a general description of the securities we may offer. Each time we offer securities pursuant to this prospectus, we will provide a prospectus supplement containing specific terms of the particular offering together with this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you invest in any securities. The prospectus supplement also may add, update or change information contained in this prospectus. This prospectus may not be used to offer and sell securities unless accompanied by the applicable prospectus supplement.

        Our common stock is listed on the NASDAQ Global Market under the symbol "EGLT." On February 10, 2016, the closing price of our common stock was $7.51.

        Investing in our securities involves significant risks. We strongly recommend that you read carefully the risks we describe in this prospectus and in any accompanying prospectus supplement, as well as the risk factors that are incorporated by reference into this prospectus from our filings made with the Securities and Exchange Commission. See "Risk Factors" on page 4 of this prospectus.

        We may sell the securities directly or to or through underwriters or dealers, and also to other purchasers or through agents. The names of any underwriters or agents that are included in a sale of securities to you, and any applicable commissions or discounts, will be stated in an accompanying prospectus supplement. In addition, the underwriters, if any, may over-allot a portion of the securities.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is February 11, 2016

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ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, (the "SEC"), using a "shelf" registration process. Under this shelf registration process, we may offer and sell from time to time any combination of the securities described in this prospectus in one or more offerings in amounts, at prices and on terms that we determine at the time of the offering, with an aggregate initial offering price of up to $150,000,000. This prospectus provides you with a general description of the securities we may offer. Each time we offer securities under this registration statement we will provide a prospectus supplement that describes the terms of the relevant offering. The prospectus supplement also may add, update or change information contained in this prospectus. Before making an investment decision, you should read carefully both this prospectus and any prospectus supplement together with the documents incorporated by reference into this prospectus as described below under the heading "Information Incorporated by Reference."

        The registration statement that contains this prospectus, including the exhibits to the registration statement and the information incorporated by reference, provides additional information about us and our securities. That registration statement can be read at the SEC website (www.sec.gov) or at the SEC public reference room, as discussed below under the heading "Where You Can Find More Information."

        You should rely only on the information provided in the registration statement, this prospectus and in any prospectus supplement, including the information incorporated by reference. We have not authorized anyone to provide you with different information. You should not assume that the information in this prospectus or any supplement to this prospectus is accurate at any date other than the date indicated on the cover page of these documents or the filing date of any document incorporated by reference, regardless of its time of delivery. We are not making an offer to sell the securities in any jurisdiction where the offer or sale is not permitted.

        We may sell our securities to or through underwriters, initial purchasers, dealers or agents, directly to purchasers or through a combination of any of these methods of sale, as designated from time to time. We and our agents reserve the sole right to accept or reject in whole or in part any proposed purchase of our securities. An applicable prospectus supplement, which we will provide each time we offer the securities, will set forth the names of any underwriters, initial purchasers, dealers or agents involved in the sale of our securities, and any related fee, commission or discount arrangements. See "Plan of Distribution."

        The terms "Egalet," the "Company," "our," "us" and "we," as used in this prospectus, refer to Egalet Corporation and its wholly-owned subsidiaries, unless we state otherwise or the context indicates otherwise.

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EGALET CORPORATION

        We are a fully integrated specialty pharmaceutical company developing, manufacturing and commercializing innovative medicines for patients with acute and chronic pain while helping to protect physicians, families and communities from the burden of prescription abuse. We are marketing two innovative pain products, SPRIX® (ketorolac tromethamine) Nasal Spray and OXAYDO^TM (oxycodone HCI, USP) tablets for oral use only—CII. SPRIX Nasal Spray, a non-steroidal anti-inflammatory drug ("NSAID"), is indicated in adult patients for the short-term (up to five days) management of moderate to moderately severe pain that requires analgesia at the opioid level. OXAYDO is the first and only approved immediate-release ("IR") oxycodone product formulated to deter abuse via snorting, for the management of acute and chronic moderate to severe pain where an opioid is appropriate.

        In addition, using our proprietary Guardian™ Technology, we are developing a pipeline of clinical-stage, opioid-based product candidates that are specifically designed to deter abuse by physical and chemical manipulation. On December 15, 2015, we submitted a new drug application for our product candidate ARYMO (morphine sulfate) extended-release tablets for the management of pain sever enough to require daily, around-the-clock opioid treatment and for which alternative treatments are inadequate. We plan to submit an NDA for our second product candidate, an abuse-deterrent, extended release oxycodone, in mid-2017. We plan to file an IND in the second half of 2016 for our third product candidate, an abuse-deterrent stimulant. Our Guardian Technology can be applied broadly across different classes of pharmaceutical products and can be used to develop combination products that include multiple active pharmaceutical ingredients with similar or different release profiles and offers us a number of long-term growth opportunities.

        Our filings with the SEC are posted on our website at www.egalet.com. The information found on our website is not part of this or any other report we file with or furnish to the SEC. The public can also obtain copies of these filings by visiting the SEC's Public Reference Room at 100 F Street NE, Washington DC 20549, or by calling the SEC at 1-800-SEC-0330 or by accessing the SEC's website at www.sec.gov.

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FORWARD-LOOKING STATEMENTS

        This registration statement on Form S-3 contains forward-looking statements within the meaning of the federal securities laws. Statements that are not historical facts, including statements about the Company's beliefs and expectations, are forward-looking statements. We may, in some cases, use terms such as "believes," "estimates," "anticipates," "expects," "plans," "intends," "may," "could," "might," "will," "should," "approximately" or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. Forward-looking statements appear in a number of places throughout this registration statements and include statements regarding our intentions, beliefs, projections, outlook, analyses or current expectations concerning, among other things, our ongoing and planned preclinical development and clinical trials, our ability to successfully commercialize Sprix and OXAYDO, the timing of and our ability to make regulatory filings and obtain and maintain regulatory approvals for our product candidates, our intellectual property position, the degree of clinical utility of our products, particularly in specific patient populations, our ability to develop commercial functions, expectations regarding clinical trial data, our results of operations, cash needs, spending of the proceeds from this offering, financial condition, liquidity, prospects, growth and strategies, the industry in which we operate and the trends that may affect the industry or us.

        Except as required by applicable law, including the securities laws of the United States and the rules and regulations of the SEC, we are under no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. You should not place undue reliance on our forward-looking statements. Although we believe that the expectations reflected in forward-looking statements are reasonable, we cannot guarantee future results or performance. Before you invest in our common stock, you should be aware that the occurrence of the events described in the "Risk Factors" included in our Annual Report on Form 10-K for the year ended December 31, 2014, and in subsequent filings, which are incorporated by reference into this prospectus, could harm our business, prospects, operating results, and financial condition.

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RISK FACTORS

        Investing in our securities involves risk. You should carefully consider the specific risks discussed or incorporated by reference into the applicable prospectus supplement, together with all the other information contained in the prospectus supplement or incorporated by reference into this prospectus and the applicable prospectus supplement. You should also consider the risks, uncertainties and assumptions discussed under the caption "Risk Factors" included in our Annual Report on Form 10-K for the year ended December 31, 2014 and in subsequent filings, which are incorporated by reference into this prospectus. These risk factors may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future or by a prospectus supplement relating to a particular offering of our securities. These risks and uncertainties are not the only risks and uncertainties we face. Additional risks and uncertainties not presently known to us, or that we currently view as immaterial, may also impair our business. If any of the risks or uncertainties described in our SEC filings or any prospectus supplement or any additional risks and uncertainties actually occur, our business, financial condition and results of operations could be materially and adversely affected. In that case, the trading price of our securities could decline and you might lose all or part of your investment.

RATIO OF EARNINGS TO FIXED CHARGES

        Our ratio of earnings to fixed charges for each of the five most recently completed fiscal years and any required interim periods will each be specified in a prospectus supplement or in a document that we file with the SEC and incorporate by reference pertaining to the issuance, if any, by us of debt securities in the future.

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USE OF PROCEEDS

        Unless otherwise indicated in the applicable prospectus supplement, we will use the net proceeds from the sale of the securities offered hereby for general corporate purposes, which include, but are not limited to, providing financing for clinical trials, acquisitions, capital expenditures, additions to working capital and expanding our commercial sales and marketing infrastructure or other corporate obligations.

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DESCRIPTION OF CAPITAL STOCK

        The following description is a general summary of the terms of the shares of common stock or shares of preferred stock that we may issue. The description below and in any prospectus supplement does not include all of the terms of the shares of common stock or shares of preferred stock and should be read together with our Third Amended and Restated Certificate of Incorporation, as amended (our "Certificate of Incorporation"), and our Amended and Restated Bylaws (our "Bylaws"), copies of which have been filed previously with the SEC. For more information on how you can obtain copies of our Certificate of Incorporation and our Bylaws, see "Where You Can Find More Information."

Common Stock

General

        Our Certificate of Incorporation provides the authority to issue 75,000,000 shares of common stock, par value $0.001 per share. At February 2, 2016, there were 25,045,554 shares of common stock outstanding. Each share of our common stock has the same relative rights and is identical in all respects to each other share of our common stock. The rights, preferences and privileges of holders of our common stock are subject to the rights, preferences and privileges of the holders of shares of any series of preferred stock that we have issued or may issue in the future.

Voting Rights

        The holders of our common stock are entitled to one vote per share on any matter to be voted upon by our stockholders. Our Certificate of Incorporation does not permit cumulative voting in connection with the election of directors.

Dividends

        The holders of our common stock are entitled to dividends, if any, as our Board of Directors may declare from time to time from funds legally available for that purpose, subject to the holders of other classes of stock, if any, at the time outstanding having prior rights as to dividends, if any.

Liquidation Rights

        Upon any voluntary or involuntary liquidation, dissolution, or winding up of our affairs, the holders of our common stock are entitled to share ratably in all assets remaining after the payment of creditors, subject to any prior liquidation distribution rights of holders of other classes of stock, if any, at the time outstanding.

Miscellaneous

        Holders of our common stock have no preemptive, conversion, redemption or sinking fund rights. The outstanding shares of our common stock are, and the shares of common stock to be offered hereby when issued will be, validly issued, fully paid and non-assessable.

NASDAQ Listing

        Our common stock is listed on the NASDAQ Global Market under the symbol "EGLT."

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is Broadridge Corporate Issuer Solutions, Inc. whose address is 44 West Lancaster Avenue, Ardmore, PA 19003.

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Preferred Stock

General

        Our Certificate of Incorporation authorizes the issuance of up to 5,000,000 shares of preferred stock, par value $0.001 per share, none of which are issued and outstanding as of the date of this prospectus. We may issue, from time to time in one or more series, the terms of which may be determined at the time of issuance by our board of directors, without further action by our stockholders, shares of preferred stock and such shares may include voting rights, preferences as to dividends and liquidation, conversion rights, redemption rights and sinking fund provisions. The shares of each series of preferred stock shall have preferences, limitations and relative rights, including voting rights, identical with those of other shares of the same series and, except to the extent provided in the description of such series, of those of other series of preferred stock.

        The issuance of any preferred stock could adversely affect the rights of the holders of common stock and, therefore, reduce the value of the common stock. The ability of our board of directors to issue preferred stock could discourage, delay or prevent a takeover or change in control.

        The description of the terms of a particular series of preferred stock in the applicable prospectus supplement will not be complete. You should refer to the applicable certificate of designation for complete information regarding a series of preferred stock. The prospectus supplement will also contain a description of U.S. federal income tax consequences relating to the preferred stock, if material.

        The terms of any particular series of preferred stock will be described in the prospectus supplement relating to that particular series of preferred stock, including, where applicable:

•

the series designation, stated value and liquidation preference of such preferred stock and the number of shares offered;



•

the offering price;



•

the dividend rate or rates (or method of calculation), the date or dates from which dividends shall accrue, and whether such dividends shall be cumulative or noncumulative and, if cumulative, the dates from which dividends shall commence to cumulate;



•

any redemption or sinking fund provisions;



•

the amount that shares of such series shall be entitled to receive in the event of our liquidation, dissolution or winding-up;



•

the terms and conditions, if any, on which shares of such series shall be convertible or exchangeable for shares of our stock of any other class or classes, or other series of the same class;



•

the voting rights, if any, of shares of such series in addition to those set forth under the caption entitled, "Voting Rights" below;



•

the status as to reissuance or sale of shares of such series redeemed, purchased or otherwise reacquired, or surrendered to us on conversion or exchange;



•

the conditions and restrictions, if any, on the payment of dividends or on the making of other distributions on, or the purchase, redemption or other acquisition by us, of our common stock or of any other class of our stock ranking junior to the shares of such series as to dividends or upon liquidation (including, but not limited to, at such times as there are arrearages in the payment of dividends or sinking fund installments);

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•

the conditions and restrictions, if any, on the creation of Company indebtedness, or on the issue of any additional stock ranking on a parity with or prior to the shares of such series as to dividends or upon liquidation; and



•

any additional dividend, liquidation, redemption, sinking or retirement fund and other rights, preferences, privileges, limitations and restrictions of such preferred stock.

        If we issue shares of preferred stock under this prospectus and any related prospectus supplement, the shares will be fully paid and non-assessable and will not have, or be subject to, any preemptive or similar rights.

Voting Rights

        The General Corporation Law of Delaware provides that the holders of preferred stock will have the right to vote separately as a class on any proposal involving fundamental changes in the rights of holders of that preferred stock. This right is in addition to any voting rights that may be provided for in the applicable certificate of designation.

Transfer Agent and Registrar

        The transfer agent and registrar for any series of preferred stock will be set forth in the applicable prospectus supplement.

Other

        Our issuance of preferred stock could decrease the amount of earnings and assets available for distribution to the holders of common stock or could adversely affect the rights and powers, including voting rights, of the holders of common stock. The issuance of preferred stock could have the effect of decreasing the market price of our common stock.

Delaware Law and Certain Provisions in our Certificate of Incorporation and our Bylaws

        The provisions of Delaware law and of our Certificate of Incorporation and our Bylaws discussed below could discourage or make it more difficult to acquire control of the Company by means of a tender offer, open market purchases, a proxy contest or otherwise, or to remove incumbent officers and directors. Our Board of Directors believes that these charter provisions are appropriate to protect our interests and the interests of our stockholders. A summary of these provisions is set forth below. This summary does not purport to be complete and is qualified in its entirety by reference to the Delaware General Corporation Law and our Certificate of Incorporation and our Bylaws.

        Delaware Anti-Takeover Law.    We are subject to Section 203 of the Delaware General Corporation Law. Section 203 generally prohibits a public Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:

•

prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;



•

upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding specified shares; or



•

at or subsequent to the date of the transaction, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by

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written consent, by the affirmative vote of at least 66²/3% of the outstanding voting stock which is not owned by the interested stockholder.

        Section 203 defines a "business combination" to include:

•

any merger or consolidation involving the corporation and the interested stockholder;



•

any sale, lease, exchange, mortgage, pledge, transfer or other disposition of 10% or more of the assets of the corporation to or with the interested stockholder;



•

subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;



•

subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or



•

the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

        In general, Section 203 defines an "interested stockholder" as any person that is:

•

the owner of 15% or more of the outstanding voting stock of the corporation;



•

an affiliate or associate of the corporation who was the owner of 15% or more of the outstanding voting stock of the corporation at any time within three years immediately prior to the relevant date; or



•

the affiliates and associates of the above.

        Certificate of Incorporation and Bylaws.    Under specific circumstances, Section 203 makes it more difficult for an "interested stockholder" to effect various business combinations with a corporation for a three-year period, although the stockholders may, by adopting an amendment to the corporation's certificate of incorporation or bylaws, elect not to be governed by this section, effective 12 months after adoption.

        Our Certificate of Incorporation and our Bylaws do not exclude us from the restrictions of Section 203. We anticipate that the provisions of Section 203 might encourage companies interested in acquiring us to negotiate in advance with our board of directors since the stockholder approval requirement would be avoided if a majority of the directors then in office approve either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder.

        Our Certificate of Incorporation and our Bylaws include a number of provisions that may have the effect of deterring hostile takeovers or delaying or preventing changes in control of the management of the Company.

        First, our Certificate of Incorporation provides that all stockholder actions must be effected at a duly called meeting of holders and not by a consent in writing.

        Second, our Bylaws provide that special meetings of the holders may be called only pursuant to a resolution adopted by a majority of the total number of authorized directors.

        Third, our Certificate of Incorporation provides that our Board of Directors can issue up to 5,000,000 shares of Preferred Stock without further action by our stockholders.

        Fourth, our Certificate of Incorporation and Bylaws provide for a classified Board of Directors in which approximately one-third of the directors are elected each year. Consequently, any potential acquirer would need to successfully complete two proxy contests in order to take control of our Board

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of Directors. As a result of the provisions of our Certificate of Incorporation and Delaware law, stockholders will not be able to cumulate votes for directors.

        Fifth, our Bylaws establish procedures, including advance notice procedures, with regard to the nomination of candidates for election as directors and stockholder proposals. These provisions of our Certificate of Incorporation and Bylaws could discourage potential acquisition proposals and could delay or prevent a change in control of the management of our company.

        Finally, our Certificate of Incorporation prohibits a business combination with an interested stockholder without the approval of the holders of 75% of all voting shares and the vote of a majority of the voting shares held by disinterested stockholders, unless it has been approved by a majority of the disinterested directors.

Indemnification

        We have included in our Certificate of Incorporation and our Bylaws provisions to eliminate the personal liability of our directors for monetary damages resulting from breaches of their fiduciary duty to the extent permitted by the Delaware General Corporation Law, and to indemnify our directors and officers to the fullest extent permitted by Section 145 of the Delaware General Corporation Law, including circumstances in which indemnification is otherwise discretionary. These provisions may have the effect of reducing the likelihood of derivative litigation against our directors and may discourage or deter stockholders or management from bringing a lawsuit against our directors for breach of their duty of care, even though such an action, if successful, might otherwise have benefited the Company and our stockholders. We believe that these provisions are necessary to attract and retain qualified persons as directors and officers.

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DESCRIPTION OF WARRANTS

        We may issue warrants for the purchase of shares of our common stock, shares of our preferred stock or debt securities. The following description sets forth certain general terms and provisions of the warrants that we may offer pursuant to this prospectus. The particular terms of the warrants and the extent, if any, to which the general terms and provisions may apply to the warrants so offered will be described in the applicable prospectus supplement.

        Warrants may be issued independently or together with other securities and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants and will not have any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

        A copy of the forms of the warrant agreement and the warrant certificate relating to any particular issue of warrants will be filed with the SEC each time we issue warrants, and you should read those documents for provisions that may be important to you. For more information on how you can obtain copies of the forms of the warrant agreement and the related warrant certificate, see "Where You Can Find More Information."

Stock Warrants

        The prospectus supplement relating to a particular issue of warrants to issue shares of our common stock or shares of our preferred stock will describe the terms of the common share warrants and preferred share warrants, including the following:

•

the title of the warrants;



•

the offering price for the warrants, if any;



•

the aggregate number of the warrants;



•

the designation and terms of the shares of common stock or shares of preferred stock that may be purchased upon exercise of the warrants;



•

the terms for changes or adjustments to the exercise price of the warrants;



•

if applicable, the designation and terms of the securities that the warrants are issued with and the number of warrants issued with each security;



•

if applicable, the date from and after which the warrants and any securities issued with the warrants will be separately transferable;



•

the number of shares of common stock or shares of preferred stock that may be purchased upon exercise of a warrant and the price at which the shares may be purchased upon exercise;



•

the dates on which the right to exercise the warrants commence and expire;



•

if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;



•

the currency or currency units in which the offering price, if any, and the exercise price are payable;



•

if applicable, a discussion of material United States federal income tax considerations;



•

anti-dilution provisions of the warrants, if any;



•

redemption or call provisions, if any, applicable to the warrants;

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any additional terms of the warrants, including terms, procedures and limitations relating to the exchange and exercise of the warrants; and



•

any other information we think is important about the warrants.

Debt Warrants

        The prospectus supplement relating to a particular issue of warrants to issue debt securities will describe the terms of those warrants, including the following:

•

the title of the warrants;



•

the offering price for the warrants, if any;



•

the aggregate number of the warrants;



•

the designation and terms of the debt securities purchasable upon exercise of the warrants;



•

the terms for changes or adjustments to the exercise price of the warrants;



•

if applicable, the designation and terms of the debt securities that the warrants are issued with and the number of warrants issued with each debt security;



•

if applicable, the date from and after which the warrants and any debt securities issued with them will be separately transferable;



•

the principal amount of debt securities that may be purchased upon exercise of a warrant and the price at which the debt securities may be purchased upon exercise;



•

the dates on which the right to exercise the warrants will commence and expire;



•

if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;



•

whether the warrants represented by the warrant certificates or debt securities that may be issued upon exercise of the warrants will be issued in registered or bearer form;



•

information relating to book-entry procedures, if any;



•

the currency or currency units in which the offering price, if any, and the exercise price are payable;



•

if applicable, a discussion of material United States federal income tax considerations;



•

anti-dilution provisions of the warrants, if any;



•

redemption or call provisions, if any, applicable to the warrants;



•

any additional terms of the warrants, including terms, procedures and limitations relating to the exchange and exercise of the warrants; and



•

any other information we think is important about the warrants.

Exercise of Warrants

        Each warrant will entitle the holder of the warrant to purchase at the exercise price set forth in the applicable prospectus supplement the number of shares of common stock, shares of preferred stock or the principal amount of debt securities being offered. Holders may exercise warrants at any time up to the close of business on the expiration date set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants are void. Holders may exercise warrants as set forth in the prospectus supplement relating to the warrants being offered.

        Until a holder exercises the warrants to purchase our shares of common stock, shares of preferred stock or debt securities, the holder will not have any rights as a holder of our shares of common stock, shares of preferred stock or debt securities, as the case may be, by virtue of ownership of warrants.

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DESCRIPTION OF DEBT SECURITIES

        The following is a general description of the terms of debt securities we may issue from time to time unless we provide otherwise in the applicable prospectus supplement. Particular terms of any debt securities we offer will be described in the prospectus supplement relating to such debt securities.

        As required by Federal law for all bonds and notes of companies that are publicly offered, any debt securities we issue will be governed by a document called an "indenture." An indenture is a contract between us and a financial institution acting as trustee on behalf of the holders of the debt securities, and is subject to and governed by the Trust Indenture Act of 1939, as amended. The trustee has two main roles. First, the trustee can enforce holders' rights against us if we default. There are some limitations on the extent to which the trustee acts on holders' behalf, described in the second paragraph under "Description of Debt Securities—Events of Default." Second, the trustee performs certain administrative duties, such as sending interest and principal payments to holders.

        Because this section is a summary, it does not describe every aspect of any debt securities we may issue or the indenture governing any such debt securities. Particular terms of any debt securities we offer will be described in the prospectus supplement relating to such debt securities, and we urge you to read the applicable indenture, which will be filed with the SEC at the time of any offering of debt securities, because it, and not this description, will define the rights of holders of such debt securities.

        A prospectus supplement will describe the particular terms of any series of debt securities we may issue, including some or all of the following:

•

the designation or title of the series of debt securities;



•

the total principal amount of the series of debt securities, the denominations in which the offered debt securities will be issued and whether the offering may be reopened for additional securities of that series and on what terms;



•

the percentage of the principal amount at which the series of debt securities will be offered;



•

the date or dates on which principal will be payable;



•

the rate or rates (which may be either fixed or variable) and/or the method of determining such rate or rates of interest, if any;



•

the date or dates from which any interest will accrue, or the method of determining such date or dates, and the date or dates on which any interest will be payable;



•

the terms for redemption, extension or early repayment, if any;



•

the currencies in which the series of debt securities are issued and payable;



•

whether the amount of payments of principal, interest or premium, if any, on a series of debt securities will be determined with reference to an index, formula or other method and how these amounts will be determined;



•

the place or places of payment, transfer, conversion and/or exchange of the debt securities;



•

the provision for any sinking fund;



•

any restrictive covenants;



•

events of default;



•

whether the series of debt securities are issuable in certificated form;



•

any provisions for legal defeasance or covenant defeasance;

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whether and under what circumstances we will pay additional amounts in respect of any tax, assessment or governmental charge and, if so, whether we will have the option to redeem the debt securities rather than pay the additional amounts (and the terms of this option);



•

any provisions for convertibility or exchangeability of the debt securities into or for any other securities;



•

whether the debt securities are subject to subordination and the terms of such subordination;



•

any listing of the debt securities on any securities exchange;



•

if applicable, a discussion of certain U.S. Federal income tax considerations, including those related to original issue discount, if applicable; and



•

any other material terms.

        The debt securities may be secured or unsecured obligations. Unless the prospectus supplement states otherwise, principal, interest and premium, if any, will be paid by us in immediately available funds.

General

        The indenture may provide that any debt securities proposed to be sold under this prospectus and the applicable prospectus supplement relating to such debt securities ("offered debt securities") and any debt securities issuable upon conversion or exchange of other offered securities ("underlying debt securities") may be issued under the indenture in one or more series.

        For purposes of this prospectus, any reference to the payment of principal of, or interest or premium, if any, on, debt securities will include additional amounts if required by the terms of the debt securities.

        Debt securities issued under an indenture, when a single trustee is acting for all debt securities issued under the indenture, are called the "indenture securities." The indenture may also provide that there may be more than one trustee thereunder, each with respect to one or more different series of securities issued thereunder. See "Description of Debt Securities—Resignation of Trustee" below. At a time when two or more trustees are acting under an indenture, each with respect to only certain series, the term "indenture securities" means the one or more series of debt securities with respect to which each respective trustee is acting. In the event that there is more than one trustee under an indenture, the powers and trust obligations of each trustee described in this prospectus will extend only to the one or more series of indenture securities for which it is trustee. If two or more trustees are acting under an indenture, then the indenture securities for which each trustee is acting would be treated as if issued under separate indentures.

        We refer you to the applicable prospectus supplement relating to any debt securities we may issue from time to time for information with respect to any deletions from, modifications of or additions to the Events of Default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection, that will be applicable with respect to such debt securities.

        We have the ability to issue indenture securities with terms different from those of indenture securities previously issued and, without the consent of the holders thereof, to reopen a previous issue of a series of indenture securities and issue additional indenture securities of that series unless the reopening was restricted when that series was created.

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Conversion and Exchange

        If any debt securities are convertible into or exchangeable for other securities, the related prospectus supplement will explain the terms and conditions of the conversion or exchange, including the conversion price or exchange ratio (or the calculation method), the conversion or exchange period (or how the period will be determined), if conversion or exchange will be mandatory or at the option of the holder or us, provisions for adjusting the conversion price or the exchange ratio and provisions affecting conversion or exchange in the event of the redemption of the underlying debt securities. These terms may also include provisions under which the number or amount of other securities to be received by the holders of the debt securities upon conversion or exchange would be calculated according to the market price of the other securities as of a time stated in the prospectus supplement.

Payment and Paying Agents

        We will pay interest to the person listed in the applicable trustee's records as the owner of the debt security at the close of business on a particular day in advance of each due date for interest, even if that person no longer owns the debt security on the interest due date. That day, often approximately two weeks in advance of the interest due date, is called the "record date." Because we will pay all the interest for an interest period to the holders on the record date, holders buying and selling debt securities must work out between themselves the appropriate purchase price. The most common manner is to adjust the sales price of the debt securities to prorate interest fairly between buyer and seller based on their respective ownership periods within the particular interest period. This prorated interest amount is called "accrued interest."

Events of Default

        Holders of debt securities of any series will have rights if an Event of Default occurs in respect of the debt securities of such series and is not cured, as described later in this subsection. The term "Event of Default" in respect of the debt securities of any series means any of the following:

•

we do not pay the principal of, or any premium on, a debt security of the series on its due date;



•

we do not pay interest on a debt security of the series or of any coupon appertaining thereto within 30 days of its due date;



•

we do not deposit any sinking fund payment in respect of debt securities of the series on its due date and we do not cure this default within five days;



•

we remain in breach of a covenant in respect of debt securities of the series for 90 days after we receive a written notice of default stating we are in breach. The notice must be sent by either the trustee or holders of at least 25% of the principal amount of debt securities of the series;



•

we file for bankruptcy or certain other events of bankruptcy, insolvency or reorganization occur; and



•

any other Event of Default occurs in respect of debt securities of the series described in the prospectus supplement.

        An Event of Default for a particular series of debt securities does not necessarily constitute an Event of Default for any other series of debt securities issued under the same or any other indenture. The trustee may withhold notice to the holders of debt securities of any default, except in the payment of principal, premium or interest, if it considers the withholding of notice to be in the best interests of the holders. However, if an Event of Default arises due to the occurrence of certain specified bankruptcy, insolvency or reorganization events, the unpaid principal, premium, if any, and accrued interest, if any, of each issue or debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

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Remedies if an Event of Default Occurs

        If an Event of Default has occurred and has not been cured or waived, the trustee or the holders of not less than 25% in principal amount of the debt securities of the affected series may declare the entire principal amount of all the debt securities of that series to be due and immediately payable. This is called a declaration of acceleration of maturity. A declaration of acceleration of maturity may be canceled by the holders of a majority in principal amount of the debt securities of the affected series if the default is cured or waived and certain other conditions are satisfied.

        Except in cases of default, where the trustee has some special duties, the trustee typically is not required to take any action under an indenture at the request of any holders unless the holders offer the trustee reasonable protection from expenses and liability (called an "indemnity"). If reasonable indemnity is provided, the holders of a majority in principal amount of the outstanding debt securities of the relevant series may direct the time, method and place of conducting any lawsuit or other formal legal action seeking any remedy available to the trustee. The trustee may refuse to follow those directions in certain circumstances.

        Before a holder is allowed to bypass the trustee and bring its own lawsuit or other formal legal action or take other steps to enforce its rights or protect its interests relating to any debt securities, the following must occur:

•

the holder must give the trustee written notice that an Event of Default has occurred and remains uncured;



•

the holders of at least 25% in principal amount of all outstanding debt securities of the relevant series must make a written request that the trustee take action because of the default and must offer reasonable indemnity to the trustee against the cost and other liabilities of taking that action;



•

the trustee must not have taken action for 60 days after receipt of the above notice and offer of indemnity; and



•

the holders of a majority in principal amount of the debt securities must not have given the trustee a direction inconsistent with the above notice during that 60-day period.

        However, a holder is entitled at any time to bring a lawsuit for the payment of money due on its debt securities on or after the due date. Each year, we will furnish to each trustee a written statement of certain of our officers certifying that to their knowledge we are in compliance with the indenture and the debt securities, or else specifying any default.

Waiver of Default

        The holders of a majority in principal amount of the relevant series of debt securities may waive a default for all such series of debt securities. If this happens, the default will be treated as if it had not occurred. No one can waive a payment default on a holder's debt security, however, without the holder's approval.

Merger or Consolidation

        Under the terms of an indenture, we may be permitted to consolidate or merge with another entity. We may also be permitted to sell all or substantially all of our assets to another entity. However, typically we may not take any of these actions unless all the following conditions are met:

•

if we do not survive such transaction or we convey, transfer or lease our properties and assets substantially as an entirety, the acquiring company must be a corporation, limited liability company, partnership or trust, or other corporate form, organized under the laws of any state of

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the United States or the District of Columbia, and such company must agree to be legally responsible for our debt securities, and, if not already subject to the jurisdiction of any state of the United States or the District of Columbia, the new company must submit to such jurisdiction for all purposes with respect to the debt securities and appoint an agent for service of process;

•

alternatively, we must be the surviving company;



•

immediately after the transaction no Event of Default will exist;



•

we must deliver certain certificates and documents to the trustee; and



•

we must satisfy any other requirements specified in the prospectus supplement relating to a particular series of debt securities.

Modification or Waiver

        There are three types of changes we may make to an indenture and the debt securities issued thereunder.

Changes Requiring Approval

        First, there are changes that we cannot make to debt securities without specific approval of all of the holders. The following is a list of the types of changes that may require specific approval:

•

change the stated maturity of the principal of or rate of interest on a debt security;



•

reduce any amounts due on a debt security;



•

reduce the amount of principal payable upon acceleration of the maturity of a security following a default;



•

at any time after a change of control has occurred, reduce any premium payable upon a change of control;



•

change the place or currency of payment on a debt security (except as otherwise described in the prospectus or prospectus supplement);



•

impair the right of holders to sue for payment;



•

adversely affect any right to convert or exchange a debt security in accordance with its terms;



•

reduce the percentage of holders of debt securities whose consent is needed to modify or amend the indenture;



•

reduce the percentage of holders of debt securities whose consent is needed to waive compliance with certain provisions of the indenture or to waive certain defaults;



•

modify any other aspect of the provisions of the indenture dealing with supplemental indentures, modification and waiver of past defaults, changes to the quorum or voting requirements or the waiver of certain covenants; and



•

change any obligation we have to pay additional amounts.

Changes Not Requiring Approval

        The second type of change does not require any vote by the holders of the debt securities. This type is limited to clarifications and certain other changes that would not adversely affect holders of the outstanding debt securities in any material respect, including the addition of covenants and guarantees. We also do not need any approval to make any change that affects only debt securities to be issued under the indenture after the change takes effect.

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Changes Requiring Majority Approval

        Any other change to the indenture and the debt securities may require the following approval:

•

if the change affects only one series of debt securities, it must be approved by the holders of a majority in principal amount of that series; and



•

if the change affects more than one series of debt securities issued under the same indenture, it must be approved by the holders of a majority in principal amount of all of the series affected by the change, with all affected series voting together as one class for this purpose.

        The holders of a majority in principal amount of all of the series of debt securities issued under an indenture, voting together as one class for this purpose, may waive our compliance obligations with respect to some of our covenants in that indenture. However, we cannot obtain a waiver of a payment default or of any of the matters covered by the bullet points included above under "Description of Debt Securities—Modification or Waiver—Changes Requiring Approval."

Further Details Concerning Voting

        When taking a vote on proposed changes to the indenture and the debt securities, we expect to use the following rules to decide how much principal to attribute to a debt security:

•

for original issue discount securities, we will use the principal amount that would be due and payable on the voting date if the maturity of these debt securities were accelerated to that date because of a default;



•

for debt securities whose principal amount is not known (for example, because it is based on an index), we will use a special rule for that debt security described in the related prospectus supplement; and



•

for debt securities denominated in one or more foreign currencies, we will use the U.S. dollar equivalent.

        Debt securities will not be considered outstanding, and therefore not eligible to vote, if we have deposited or set aside in trust money for their payment or redemption. Debt securities will also not be eligible to vote if they have been fully defeased as described later under "Description of Debt Securities—Defeasance—Legal Defeasance."

        We generally will be entitled to set any day as a record date for the purpose of determining the holders of outstanding indenture securities that are entitled to vote or take other action under the indenture. If we set a record date for a vote or other action to be taken by holders of one or more series, that vote or action may be taken only by persons who are holders of outstanding indenture securities of those series on the record date and must be taken within 11 months following the record date.

        Book-entry and other indirect holders will need to consult their banks or brokers for information on how approval may be granted or denied if we seek to change the indenture or the debt securities or request a waiver.

Defeasance

        The following provisions will be applicable to each series of debt securities unless we state in the applicable prospectus supplement that the provisions of covenant defeasance and legal defeasance will not be applicable to that series.

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Covenant Defeasance

        We can make the deposit described below and be released from some of the restrictive covenants in the indenture under which the particular series was issued. This is called "covenant defeasance." In that event, the holders would lose the protection of those restrictive covenants but would gain the protection of having money and government securities set aside in trust to repay holders' debt securities. If applicable, a holder also would be released from the subordination provisions described under "Description of Debt Securities—Indenture Provisions—Subordination" below. In order to achieve covenant defeasance, we must do the following:

•

If the debt securities of the particular series are denominated in U.S. dollars, we must deposit in trust for the benefit of all holders of such debt securities a combination of money and U.S. government or U.S. government agency notes or bonds that will generate enough cash to make interest, principal and any other payments on the debt securities on their various due dates;



•

We may be required to deliver to the trustee a legal opinion of our counsel confirming that, under current U.S. Federal income tax law, we may make the above deposit without causing the holders to be taxed on the debt securities any differently than if we did not make the deposit and just repaid the debt securities ourselves at maturity; and



•

We must deliver to the trustee certain documentation stating that all conditions precedent to covenant defeasance have been complied with.

        If we accomplish covenant defeasance, holders can still look to us for repayment of the debt securities if there were a shortfall in the trust deposit or the trustee is prevented from making payment. In fact, if one of the remaining Events of Default occurred (such as our bankruptcy) and the debt securities became immediately due and payable, there might be a shortfall. Depending on the event causing the default, holders may not be able to obtain payment of the shortfall.

Legal Defeasance

        As described below, we can legally release ourselves from all payment and other obligations on the debt securities of a particular series (called "legal defeasance"), (1) if there is a change in U.S. Federal tax law that allows us to effect the release without causing the holders to be taxed any differently than if the release had not occurred, and (2) if we put in place the following other arrangements for holders to be repaid:

•

If the debt securities of the particular series are denominated in U.S. dollars, we must deposit in trust for the benefit of all holders of such debt securities a combination of money and U.S. government or U.S. government agency notes or bonds that will generate enough cash to make interest, principal and any other payments on the debt securities on their various due dates;



•

We may be required to deliver to the trustee a legal opinion confirming that there has been a change in current U.S. Federal tax law or an Internal Revenue Service ruling that allows us to make the above deposit without causing the holders to be taxed on the debt securities any differently than if we did not make the deposit and just repaid the debt securities ourselves at maturity. Under current U.S. Federal tax law, the deposit and our legal release from the debt securities would be treated as though we paid each holder its share of the cash and notes or bonds at the time the cash and notes or bonds were deposited in trust in exchange for its debt securities and holders would recognize gain or loss on the debt securities at the time of the deposit; and



•

We must deliver to the trustee a legal opinion and officers' certificate stating that all conditions precedent to legal defeasance have been complied with.

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        If we ever did accomplish legal defeasance, as described above, holders would have to rely solely on the trust deposit for repayment of the debt securities. Holders could not look to us for repayment in the unlikely event of any shortfall. Conversely, the trust deposit would most likely be protected from claims of our lenders and other creditors if we ever became bankrupt or insolvent. If applicable, holders would also be released from the subordination provisions described later under "Description of Debt Securities—Indenture Provisions—Subordination."

Resignation of Trustee

        Each trustee may resign or be removed with respect to one or more series of indenture securities provided that a successor trustee is appointed to act with respect to such series. In the event that two or more persons are acting as trustee with respect to different series of indenture securities under the indenture, each of the trustees will be a trustee of a trust separate and apart from the trust administered by any other trustee.

Indenture Provisions—Subordination

        Upon any distribution of our assets upon our dissolution, winding up, liquidation or reorganization, the payment of the principal of (and premium, if any) and interest on any indenture securities denominated as subordinated debt securities is to be subordinated to the extent provided in the indenture in right of payment to the prior payment in full of all Senior Indebtedness (defined below), but our obligation to holders to make payment of the principal of (and premium, if any) and interest on such subordinated debt securities will not otherwise be affected. In addition, no payment on account of principal (or premium, if any), interest or sinking fund, if any, may be made on such subordinated debt securities at any time unless full payment of all amounts due in respect of the principal (and premium, if any), interest and sinking fund, if any, on Senior Indebtedness has been made or duly provided for in money or money's worth.

        In the event that, notwithstanding the foregoing, any payment from us is received by the trustee in respect of subordinated debt securities or by the holders of any of such subordinated debt securities before all Senior Indebtedness is paid in full, the payment or distribution must be paid over to the holders of the Senior Indebtedness or on their behalf for application to the payment of all the Senior Indebtedness remaining unpaid until all the Senior Indebtedness has been paid in full, after giving effect to any concurrent payment or distribution to the holders of the Senior Indebtedness. Subject to the payment in full of all Senior Indebtedness, the holders of such subordinated debt securities will be subrogated to the rights of the holders of the Senior Indebtedness to the extent of payments made to the holders of the Senior Indebtedness out of the distributive share of such subordinated debt securities.

        By reason of this subordination, in the event of a distribution of our assets upon our insolvency, certain of our senior creditors may recover more, ratably, than holders of any subordinated debt securities. The related indenture will provide that these subordination provisions will not apply to money and securities held in trust under the defeasance provisions of the indenture.

        "Senior Indebtedness" will be defined in an applicable indenture as the principal of (and premium, if any) and unpaid interest on:

•

our indebtedness (including indebtedness of others guaranteed by us), whenever created, incurred, assumed or guaranteed, for money borrowed (other than indenture securities issued under the indenture and denominated as subordinated debt securities), unless in the instrument creating or evidencing the same or under which the same is outstanding it is provided that this indebtedness is not senior or prior in right of payment to the subordinated debt securities; and



•

renewals, extensions, modifications and refinancings of any of such indebtedness.

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        The prospectus supplement accompanying any series of indenture securities denominated as subordinated debt securities will set forth the approximate amount of our Senior Indebtedness outstanding as of a recent date.

Trustee

        We intend to name the indenture trustee for each series of indenture securities in the related prospectus supplement.

Certain Considerations Relating to Foreign Currencies

        Debt securities denominated or payable in foreign currencies may entail significant risks. These risks include the possibility of significant fluctuations in the foreign currency markets, the imposition or modification of foreign exchange controls and potential illiquidity in the secondary market. These risks will vary depending upon the currency or currencies involved and will be more fully described in the applicable prospectus supplement.

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DESCRIPTION OF RIGHTS

        The following is a general description of the terms of the rights we may issue from time to time unless we provide otherwise in the applicable prospectus supplement. Particular terms of any rights we offer will be described in the prospectus supplement relating to such rights.

General

        We may issue rights to purchase common stock, preferred stock, debt securities or units. Rights may be issued independently or together with other securities and may or may not be transferable by the person purchasing or receiving the rights. In connection with any rights offering to our stockholders, we may enter into a standby underwriting, backstop or other arrangement with one or more underwriters or other persons pursuant to which such underwriters or other persons would purchase any offered securities remaining unsubscribed for after such rights offering. In connection with a rights offering to our stockholders, we would distribute certificates evidencing the rights and a prospectus supplement to our stockholders on or about the record date that we set for receiving rights in such rights offering.

        The applicable prospectus supplement will describe the following terms of any rights we may issue, including some or all of the following:

•

the title and aggregate number of the rights;



•

the subscription price or a formula for the determination of the subscription price for the rights and the currency or currencies in which the subscription price may be payable;



•

if applicable, the designation and terms of the securities with which the rights are issued and the number of rights issued with each such security or each principal amount of such security;



•

the number or a formula for the determination of the number of the rights issued to each stockholder;



•

the extent to which the rights are transferable;



•

in the case of rights to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one right;



•

in the case of rights to purchase common stock or preferred stock, the type of stock and number of shares of stock purchasable upon exercise of one right;



•

the date on which the right to exercise the rights will commence, and the date on which the rights will expire (subject to any extension);



•

if applicable, the minimum or maximum amount of the rights that may be exercised at any one time;



•

the extent to which such rights include an over-subscription privilege with respect to unsubscribed securities;



•

if applicable, the procedures for adjusting the subscription price and number of shares of common stock or preferred stock purchasable upon the exercise of each right upon the occurrence of certain events, including stock splits, reverse stock splits, combinations, subdivisions or reclassifications of common stock or preferred stock;



•

the effect on the rights of any merger, consolidation, sale or other disposition of our business;



•

the terms of any rights to redeem or call the rights;



•

information with respect to book-entry procedures, if any;

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•

the terms of the securities issuable upon exercise of the rights;



•

if applicable, the material terms of any standby underwriting, backstop or other purchase arrangement that we may enter into in connection with the rights offering;



•

if applicable, a discussion of certain U.S. Federal income tax considerations; and



•

any other terms of the rights, including terms, procedures and limitations relating to the exchange and exercise of the rights.

Exercise of Rights

        Each right will entitle the holder to purchase for cash or other consideration such shares of stock or principal amount of securities at the subscription price as shall in each case be set forth in, or be determinable as set forth in, the prospectus supplement relating to the rights offered thereby. Rights may be exercised as set forth in the applicable prospectus supplement beginning on the date specified therein and continuing until the close of business on the expiration date set forth in the prospectus supplement relating to the rights offered thereby. After the close of business on the expiration date, unexercised rights will become void.

        Upon receipt of payment and a subscription certificate properly completed and duly executed at the corporate trust office of the subscription agent or any other office indicated in the prospectus supplement, we will, as soon as practicable, forward the securities purchasable upon such exercise. If less than all of the rights represented by such subscription certificate are exercised, a new subscription certificate will be issued for the remaining rights. If we so indicate in the applicable prospectus supplement, holders of the rights may surrender securities as all or part of the exercise price for rights.

        We may determine to offer any unsubscribed offered securities directly to stockholders, persons other than stockholders, to or through agents, underwriters or dealers or through a combination of such methods, including pursuant to standby underwriting, backstop or other arrangements, as set forth in the applicable prospectus supplement.

        Prior to exercising their rights, holders of rights will not have any of the rights of holders of the securities purchasable upon subscription, including, in the case of rights to purchase common stock or preferred stock, the right to receive dividends, if any, or payments upon our liquidation, dissolution or winding up or to exercise any voting rights or, in the case of rights to purchase debt securities, the right to receive principal, premium, if any, or interest payments, on the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture.

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DESCRIPTION OF UNITS

        We may issue units comprising one or more securities described in this prospectus in any combination. The following description sets forth certain general terms and provisions of the units that we may offer pursuant to this prospectus. The particular terms of the units and the extent, if any, to which the general terms and provisions may apply to the units so offered will be described in the applicable prospectus supplement.

        Each unit will be issued so that the holder of the unit also is the holder of each security included in the unit. Thus, the unit will have the rights and obligations of a holder of each included security. Units will be issued pursuant to the terms of a unit agreement, which may provide that the securities included in the unit may not be held or transferred separately at any time or at any time before a specified date. A copy of the forms of the unit agreement and the unit certificate relating to any particular issue of units will be filed with the SEC each time we issue units, and you should read those documents for provisions that may be important to you. For more information on how you can obtain copies of the forms of the unit agreement and the related unit certificate, see "Where You Can Find More Information."

        The prospectus supplement relating to any particular issuance of units will describe the terms of those units, including, to the extent applicable, the following:

•

the designation and terms of the units and the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;



•

any provision for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and



•

whether the units will be issued in fully registered or global form.

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PLAN OF DISTRIBUTION

        We may sell the securities offered by this prospectus in any one or more of the following ways from time to time:

•

to or through one or more underwriters, initial purchasers, brokers or dealers;



•

through agents to investors or the public;



•

in short or long transactions;



•

through put or call option transactions relating to our common stock;



•

directly to agents or other purchasers;



•

in "at the market offerings" within the meaning of Rule 415(a)(4) of the Securities Act, to or through a market maker or into an existing trading market, on an exchange or otherwise;



•

though a combination of any such methods of sale; or



•

through any other method described in the applicable prospectus supplement.

        The applicable prospectus supplement will set forth the terms of the offering and the method of distribution and will identify any firms acting as underwriters, initial purchasers, dealers or agents in connection with the offering, including:

•

the terms of the offering;



•

the names of any underwriters, dealers or agents;



•

the name or names of any managing underwriter or underwriters;



•

the purchase price of the securities and the proceeds to us from the sale;



•

any over-allotment options under which the underwriters may purchase additional shares of common stock from us;



•

any underwriting discounts, concessions, commissions or agency fees and other items constituting compensation to underwriters, dealers or agents;



•

any delayed delivery arrangements;



•

any public offering price;



•

any discounts or concessions allowed or re-allowed or paid by underwriters or dealers to other dealers; or



•

any securities exchange or market on which the common stock offered in the prospectus supplement may be listed.

        If we use underwriters for a sale of securities, the underwriters will acquire the securities for their own account for resale to the public, either on a firm commitment basis or a best efforts basis. The underwriters may resell the securities in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Underwriters may offer the securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. If an underwriter or underwriters are used in the sale of securities hereunder, an underwriting agreement will be executed with the underwriter or underwriters at the time an agreement for sale is reached. Unless we inform you otherwise in the applicable prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions. We may change from time to time any public offering price and any discounts or concessions the underwriters allow or pay to dealers.

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        During and after an offering through underwriters, the underwriters may purchase and sell the securities in the open market. These transactions may include overallotment and stabilizing transactions and purchases to cover syndicate short positions created in connection with the offering. The underwriters may also impose a penalty bid, which means that selling concessions allowed to syndicate members or other broker-dealers for the offered securities sold for their account may be reclaimed by the syndicate if the offered securities are repurchased by the syndicate in stabilizing or covering transactions. These activities may stabilize, maintain or otherwise affect the market price of the offered securities, which may be higher than the price that might otherwise prevail in the open market. If commenced, the underwriters may discontinue these activities at any time.

        Some or all of the securities that we offer though this prospectus may be new issues of securities with no established trading market. Any underwriters to whom we sell our securities for public offering and sale may make a market in those securities, but they will not be obligated to do so and they may discontinue any market making at any time without notice. Accordingly, we cannot assure you of the liquidity of, or continued trading markets for, any securities that we offer.

        If dealers are used for the sale of securities, we, or an underwriter, will sell the securities to them as principals. The dealers may then resell those securities to the public at varying prices determined by the dealers at the time of resale. We will include in the applicable prospectus supplement the names of the dealers and the terms of the transaction.

        We may also sell the securities through agents designated from time to time. In the applicable prospectus supplement, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable to the agent. Unless we inform you otherwise in the applicable prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

        We may sell the securities directly in transactions not involving underwriters, dealers or agents.

        We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. We will describe the terms of any such sales in the prospectus supplement.

        Underwriters, dealers and agents that participate in the distribution of the securities may be underwriters as defined in the applicable securities laws and any discounts or commissions they receive from us and any profit on their resale of the securities may be treated as underwriting discounts and commissions under the applicable securities laws. We will identify in the applicable prospectus supplement any underwriters, dealers or agents and will describe their compensation. We may have agreements with the underwriters, dealers and agents to indemnify them against specified civil liabilities, including liabilities under the applicable securities laws.

        Underwriters, dealers and agents may engage in transactions with or perform services for us in the ordinary course of their businesses for which they may receive customary fees and reimbursement of expenses.

        We may use underwriters with whom we have a material relationship. We will describe the nature of such relationship in the applicable prospectus supplement.

        Under the securities laws of some states, the securities offered by this prospectus may be sold in those states only through registered or licensed brokers or dealers.

        We may enter into hedging transactions with broker-dealers and the broker-dealers may engage in short sales of the securities in the course of hedging the positions they assume with us, including, without limitation, in connection with distributions of the securities by those broker-dealers. We may enter into option or other transactions with broker-dealers that involve the delivery of the securities offered hereby to the broker-dealers, who may then resell or otherwise transfer those securities. We may also loan or pledge the securities offered hereby to a broker-dealer and the broker-dealer may sell the securities offered hereby so loaned or upon a default may sell or otherwise transfer the pledged securities offered hereby.

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LEGAL MATTERS

        The validity of the securities being offered hereby will be passed upon for us by Dechert LLP, New York, New York.

EXPERTS

        The audited financial statements incorporated by reference in this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the report of Grant Thornton LLP, independent registered public accountants, upon the authority of said firm as experts in accounting and auditing.

        The statements of assets acquired of SPRIX Nasal Spray (A Product Line of Luitpold Pharmaceuticals, Inc.), as of December 31, 2014 and March 31, 2014, and the related statements of net revenues and direct expenses for the periods then ended, have been incorporated by reference herein and in the registration statement in reliance upon the report of KPMG LLP, independent registered public accounting firm, and upon the authority of said firm as experts in accounting and auditing. The audit report covering the abbreviated financial statements of SPRIX Nasal Spray (A Product Line of Luitpold Pharmaceuticals, Inc.) contains an emphasis of matter paragraph that draws attention to Note 1 to the abbreviated financial statements, which describes that the abbreviated financial statements were prepared to present the SPRIX assets acquired by Egalet US, Inc. pursuant to a product acquisition agreement, and are not intended to be a complete presentation of SPRIX's assets and liabilities. The audit report was not modified with respect to this matter.

WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and other reports, proxy and information statements and other information with the Securities and Exchange Commission. Copies of these materials may be inspected and copied at the public reference facilities maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of its public reference room. The SEC maintains a website that contains reports, proxy statements and other information regarding us. The address of the SEC website is http://www.sec.gov. We maintain a website at www.egalet.com. Information contained on our website is not incorporated into this prospectus and you should not consider information contained on our website to be part of this prospectus or any prospectus supplement.

INFORMATION INCORPORATED BY REFERENCE

        The SEC allows us to "incorporate by reference" into this prospectus the information contained in documents that we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC before the date of this prospectus, while information that we file later with the SEC will automatically update and supersede prior information. Any information so updated and superseded shall not be deemed, except as so updated and superseded, to constitute a part of this prospectus. We incorporate by reference the documents listed below and any future filings we will make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, prior to the termination of the offering. Notwithstanding the foregoing, unless specifically stated to the contrary, none of the information that is not deemed "filed" with the SEC, including information furnished under Items 2.02 or 7.01 of any Current Report on Form 8-K, will be incorporated by reference into, or otherwise included in, this prospectus:

1.

our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 filed with the SEC on March 16, 2015;

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2.

our Quarterly Report on Form 10-Q for the fiscal quarters ended March 31, 2015, June 30, 2015 and September 30, 2015, as filed with the SEC on May 8, 2015, August 7, 2015 and November 6, 2015, respectively;



3.

our Current Reports on Form 8-K originally filed with the Commission on January 12, 2015, January 13, 2015 (as amended March 25, 2015), January 22, 2015, February 12, 2015, March 11, 2015, March 18, 2015, March 23, 2015, March 25, 2015, March 25, 2015, April 2, 2015, April 6, 2015, April 8, 2015, April 14, 2015, May 19, 2015, June 4, 2015, June 10, 2015, June 16, 2015, June 19, 2015, June 25, 2015, June 29, 2015, June 30, 2015, July 1, 2015, July 2, 2015, July 28, 2015, July 31, 2015, September 9, 2015, September 10, 2015, September 29, 2015, November 16, 2015, November 20, 2015, December 2, 2015, December 9, 2015, December 15, 2015 and January 7, 2016; and



4.

our Definitive Proxy Statement on Schedule 14A, which was filed with the Commission on April 28, 2015, to the extent incorporated by reference into the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2014.

        We make available, free of charge, through our website our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. You may also obtain, free of charge, a copy of any of these documents (other than exhibits to these documents unless the exhibits are specifically incorporated by reference into these documents or referred to in this prospectus) by writing or calling us at the following address and telephone number:

Egalet Corporation
460 E. Swedesford Road
Suite 1050
Wayne, PA 19087
(610) 833-4200

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                      16,666,667 Shares of Common Stock
Warrants to Purchase up to 16,666,667 Shares of Common Stock

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PROSPECTUS SUPPLEMENT

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Sole Book-Running Manager

Cantor Fitzgerald & Co.

July 6, 2017

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