SELLING STOCKHOLDERS

        We are registering for resale pursuant to this prospectus 183,000 shares of our common stock held by the stockholders identified below.

        The table below presents information regarding the beneficial ownership of outstanding shares of common stock by the selling stockholders and the shares that such selling stockholder may sell or otherwise dispose of from time to time under this prospectus. Information concerning the selling stockholders may change from time to time, and any changed information will be presented in a prospectus supplement if and when necessary and required. The shares of our common stock covered by this prospectus may also be sold by certain transferees or successors-in-interest of the selling stockholders.

        The number of shares of common stock in the column "Number of Shares Offered Hereby" represents all of the shares of common stock that the respective selling stockholders may offer under this prospectus. In addition, the table assumes that the selling stockholders sell all of such shares. However, because the selling stockholders may offer from time to time all or some of such shares under this prospectus, or in another permitted manner, we cannot assure you as to the actual number of shares that will be sold or otherwise disposed of by the selling stockholders or that will be held byupon the selling stockholders after completion of such sales.

        We have determined beneficial ownership in accordance with the rulesconversion of the Securities and Exchange Commission. In computing the number of shares beneficially owned by a person and the percentage ownership of that person, shares of common stock subject to options held by that person that are currently exercisable or exercisable within 60 days of January 15, 2008 are deemed outstanding. Such shares, however, are not deemed outstanding for the purposes of computing the percentage ownership of any other person. Except as indicated in the footnotes to the following table or pursuant to applicable community property laws, each of the selling stockholders have sole voting and investment power with respect to the shares set forth opposite such selling stockholder's name. The percentage of beneficial ownership is based on 28,625,833 shares of voting common stock outstanding on January 15, 2008.senior secured convertible notes.

*

Less than 1%.

(1)

Includes 502,188 shares beneficially owned by Cross Atlantic Partners IV, K/S, 93,658 shares beneficially owned by Nordea Bank Danmark, A/S and 13,274 shares issuable upon the exercise of stock options that are owned by Sandra Panem, Ph.D, for the benefit of Cross Atlantic Partners IV, K/S. Cross Atlantic Partners has voting and dispository authority over the shares owned by Nordea Bank. In addition to the sale by Cross Atlantic Partners of 83,000 shares pursuant to this prospectus (as indicated in the table above), following the date of this prospectus and in accordance with the terms of certain agreements between Nordea Bank and Cross Atlantic Partners IV, Nordea Bank may sell up to 17,000 shares in the open market. Dr. Panem, who has been a member of our Board of Directors since, 1998, is a partner of Cross Atlantic Partners and exercises investment and voting power over these shares. Dr. Panem disclaims beneficial ownership of these shares. The address of Cross Atlantic Partners IV, K/S is 551 Madison Avenue, New York, NY 10022.

DESCRIPTION OF SECURITIES

        The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement relating to any securities the particular terms of the securities offered by that prospectus supplement. If indicated in the applicable prospectus supplement, the terms of the securities that we offer may differ from the terms summarized below. We will also include information in the prospectus supplement, where applicable, about material United States federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.

        We may sell, from time to time, in one or more offerings:

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common stock;



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preferred stock;



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debt securities; and



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warrants.

        In addition, the selling stockholders may sell common stock from time to time, in one or more offerings.

Common Stock

We have the authority to issue 80,000,000 shares of common stock, par value $0.001 per share. As of September 30, 2007, 28,574,344June 26, 2020, there were 47,981,098 shares of our voting common stock were issued and outstanding (not including 29,304 shares of common stock that were held in treasury), and a maximum of 3,074,0946,720,805 shares of common stock were issuable upon the exercise of outstanding options.options and the vesting and settlement of restricted stock units.

The following description of our common stock is only a summary and is subject to and qualified in its entirety by reference to our amended and restated certificate of incorporation.incorporation (our “certificate of incorporation”), and our bylaws, as amended (our “bylaws”). Holders of common stock have one vote per share and have no preemption rights. Holders of common stock have the right to participate ratably in all distributions, whether of dividends or assets in liquidation, dissolution or winding up, subject to any superior rights of holders of preferred stock outstanding at the time. See "Preferred Stock" below. There are no redemption or sinking fund provisions applicable to the common stock.

        Registrar and TransferComputershare Trust Company, N.A. is the transfer agent and registrar for our common stock. Their address is 10 Commerce Drive, Cranford, NJ 07016P.O. Box 505000, Louisville, KY 40233-5000 and their telephone number is (800) 368-5948.

Preferred Stock

        We have the authority to issue 20,000,000 shares of preferred stock. As of September 30, 2007, no shares of our preferred stock were outstanding. The description of preferred stock provisions set forth below is only a summary and is subject to and qualified in its entirety by reference to our amended and restated certificate of incorporation and the certificate of designations relating to any series of preferred stock.

        The board of directors has the right, without the consent of holders of common stock, to designate and issue one or more series of preferred stock, which may be convertible into common stock at a ratio determined by the board. A series of preferred stock may bear rights superior to common stock as to voting, dividends, redemption, distributions in liquidation, dissolution, or winding up, and other relative rights and preferences. The board may set the following terms of any series of preferred stock, and a prospectus supplement will specify these terms for any series offered:

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the number of shares constituting the series and the distinctive designation of the series;

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dividend rates, whether dividends are cumulative, and if so, from what date; and the relative rights of priority of payment of dividends;



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voting rights and the terms of the voting rights;



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conversion privileges and the terms and condition of conversion, including provision for adjustment of the conversion rate;



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redemption rights and the terms and conditions of redemption, including the date or dates upon or after which shares may be redeemable, and the amount per share payable in case of redemption, which may vary under different conditions and at different redemption dates;



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sinking fund provisions for the redemption or purchase of shares;



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rights in the event of voluntary or involuntary liquidation, dissolution or winding up of the corporation, and the relative rights of priority of payment; and



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any other relative powers, preferences, rights, privileges, qualifications, limitations and restrictions of the series.

        The preferred stock will, if issued, be fully paid and nonassessable. The rights of the holders of preferred stock will be subordinate to those of our general creditors.

Debt Securities

        The following description, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provision of any debt securities that we may offer under this prospectus. While the terms we have summarized below will apply generally to any future debt securities we may offer, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities we may offer under a prospectus supplement may differ from the terms described below. For any debt securities that we may offer, an indenture (and any relevant supplemental indenture) will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus, or as an exhibit to a current report on Form 8-K, incorporated by reference in this prospectus.

        With respect to any debt securities that we issue, we will issue such debt securities under an indenture, which we would enter into with the trustee named in the indenture. Any indenture would be qualified under the Trust Indenture Act of 1939.

        With respect to any debt securities that we issue, we will describe in each prospectus supplement the following terms relating to a series of debt securities:

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the title;



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the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;



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any limit on the amount that may be issued;



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whether or not we will issue the series of debt securities in global form, and if so, the terms and who the depository will be;



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the maturity date;



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the principal amount due at maturity;

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whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a United States person for tax purposes, and whether we can redeem the debt securities if we have to pay such additional amounts;



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the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;



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whether or not the debt securities will be convertible into shares of common stock or preferred stock and, if so, the terms of such conversion;



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whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;



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the terms of the subordination of any series of subordinated debt;



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the place where payments will be payable;



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restrictions on transfer, sale or other assignment, if any;



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our right, if any, to defer payment or interest and the maximum length of any such deferral period;



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the date, if any, after which and the conditions upon which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemptions provisions;



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the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder's option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;



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whether the indenture will restrict our ability to pay dividends or will require us to maintain any asset ratios or reserves;



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whether we will be restricted from incurring any additional indebtedness, issuing additional securities, or entering into a merger, consolidation or sale of our business;



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a discussion of any material or special United States federal income tax considerations applicable to the debt securities;



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information describing any book-entry features;



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provisions for a sinking fund purchase or other analogous fund, if any;



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any provisions for payment of additional amounts for taxes;



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whether the debt securities are to be offered at a price such that they will be deemed to be offered at an "original issue discount" as defined in paragraph (a) of Section 1273 of the Internal Revenue Code of 1986, as amended;



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the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;



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events of default;



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whether we and/or the debenture trustee may change an indenture without the consent of any holders;



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the form of debt security and how it may be exchanged and transferred;

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description of the debenture trustee and paying agent, and the method of payments; and



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any other specified terms, preferences, rights or limitations of, or restrictions on, the debt securities and any terms that may be required by us or advisable under applicable laws or regulations.

Warrants

        The following description, together with the additional information we may include in any applicable prospectus supplement, summarizes the material terms and provisions of any warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. With respect to any warrants that we offer, specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a current report on Form 8-K, incorporated by reference in this prospectus.

        General.    With respect to any warrants that we offer, we will describe in the applicable prospectus supplement the terms of the series of warrants, including:

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the offering price and aggregate number of warrants offered;



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the currency for which the warrants may be purchased;



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



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if applicable, the date on and after which the warrants and the related securities will be separately transferable;



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in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon exercise;



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in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at which, and currently in which, this principal amount of debt securities may be purchased upon exercise;



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the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreement and the warrants;



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



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any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;



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



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the manner in which the warrant agreement and warrants may be modified;



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federal income tax consequences of holding or exercising the warrants;



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the terms of the securities issuable upon exercise of the warrants; and



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any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

        Before exercising their warrants, the holders of such warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

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in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or



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in the case of warrants 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 voting rights, if any.

        Exercise of Warrants.    With respect to any warrants that we issue, each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to 5:00 P.M. New York time on the expiration date set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

        Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

        Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for the warrants ("cashless exercise").

        Enforceability of Rights by Holders of Warrants.    With respect to any warrants that we issue, each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

DELAWARE LAW AND CERTAIN CHARTER AND BYLAW PROVISIONS

Section 203 of the Delaware General Corporation Law

We are subject to Section 203 of the Delaware General Corporation Law, which, subject to certain exceptions, prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the time that such stockholder became an interested stockholder, unless:

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prior to such time, the board of directors approved either the business combination or the transaction that resulted in the stockholder becoming an interested holder;

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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 for purposes of determining the number of shares outstanding those shares owned (a) by persons who are directors and also officers and (b) by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or



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at or subsequent to such time, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least two-thirds of the outstanding voting stock which is not owned by the interested stockholder.

In general, Section 203 defines "business combination"“business combination” to include the followingfollowing:

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any merger or consolidation involving the corporation and the stockholder;



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any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;



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



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



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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 "interested stockholder"“interested stockholder” as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by such entity or person.

Certificate of Incorporation and Bylaws

Our amended and restated certificate of incorporation and amended and restated bylaws include a number of provisions that may have the effect of deterring hostile takeovers or delaying or preventing changes in control or our management. For example, our amended and restated certificate of incorporation authorizes the issuance of up to 20,000,000 shares of preferred stock, par value $.001 per share.share, of which 1,000,000 shares have been designated as Series A Junior Participating Preferred Stock. The board of directors has the authority, without approval of the stockholders, to issue and determine the rights and preferences of series of preferred stock. The ability to authorize and issue preferred stock with voting or other rights or preferences makes it possible for our board of directors to issue preferred stock with super voting, special approval, dividend or other rights or preferences on a discriminatory basis that could impede the success of any attempt to acquire us.

Our amended and restated certificate of incorporation and amended and restated bylaws also provide that our board of directors is divided into three classes, each serving staggered three-year terms ending at the annual meeting of our stockholders. All directors elected to our classified board of directors will serve until the election and qualification of their respective successors or their earlier resignation or removal. Members of the board of directors may only be removed for cause and only by the affirmative vote of 75% of our outstanding voting stock. These provisions are likely to increase the time required for stockholders to change the composition of our board of directors.

Our amended and restated certificate of incorporation and amended and restated bylaws provide that a meeting of stockholders may only be called by our board of directors, the chairman of our board

of directors or our chief executive officer. Our amended and restated bylaws also specify requirements as to the form and content of a stockholder'sstockholder’s notice. The provisions may delay or preclude stockholders from calling a meeting of stockholders, bringing matters before a meeting of stockholders or from making nominations for directors at a stockholders'stockholders’ meeting, which could delay or deter takeover attempts or changes in management. Our amended and restated certificate of incorporation also does not provide for cumulative voting. The absence of cumulative voting may make it more difficult for stockholders owning less than a majority of our stock to elect any directors to our board of directors.

PRIVATE EXCHANGE OF CONVERTIBLE NOTES

On December 24, 2019, we completed the private exchange of $276.0 million aggregate principal amount of our outstanding 1.75% Convertible Senior Notes due 2021, or the 2021 Notes, for a combination of newly issued senior secured convertible notes and cash. For each $1,000 principal amount of exchanged 2021 notes, we issued $750 principal amount of senior secured convertible notes and made a cash payment of $200, which we refer to as the exchange. In the aggregate, we issued approximately $207.0 million aggregate principal amount of senior secured convertible notes and paid approximately $55.2 million in cash to participating holders. The exchange was conducted with a limited number of institutional holders of the 2021 notes pursuant to exchange agreements dated as of December 20, 2019.

The senior secured convertible notes were issued pursuant to an indenture, dated as of December 23, 2019, among us, our wholly owned subsidiary, Civitas Therapeutics, Inc. (along with any domestic subsidiaries acquired or formed after the date of issuance, the guarantors), and Wilmington Trust, National Association, as trustee and collateral agent. The senior secured convertible notes are senior obligations of us and the guarantors, secured by a first priority security interest in substantially all of our assets and the assets of the guarantors, subject to certain exceptions described in the security agreement, dated as of December 23, 2019, between the grantors party thereto and Wilmington Trust, National Association, as collateral agent.

The senior secured convertible notes will mature on December 1, 2024 unless earlier converted in accordance with their terms prior to such date. Interest on the senior secured convertible notes will be payable semi-annually in arrears at a rate of 6.00% per annum on each June 1 and December 1, beginning on June 1, 2020. We may elect to pay interest in cash or shares of our common stock, subject to the satisfaction of certain conditions. If we elect to pay interest in shares of our common stock, such common stock will have a per share value equal to 95% of the daily volume-weighted average price for the 10 trading days ending on and including the trading day immediately preceding the relevant interest payment date.

The senior secured convertible notes will be convertible at the option of the holder into shares of our common stock at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date. The initial conversion rate for the senior secured convertible notes is 285.7142 shares of our common stock per $1,000 principal amount of senior secured convertible notes, which is equivalent to an initial conversion price of approximately $3.50 per share of common stock. The conversion rate is subject to adjustment in certain circumstances as described in the indenture, including in the event of a make-whole fundamental change, in which case the conversion rate would increase up to 561.7977 shares of our common stock per $1,000 principal amount of senior secured convertible notes.

We may elect to settle conversions of the senior secured convertible notes in cash, shares of our common stock or a combination of cash and shares of our common stock. Holders who convert their senior secured convertible notes prior to June 1, 2023 (other than in connection with a make-whole fundamental change) also will be entitled to an interest make-whole payment equal to the sum of all regularly scheduled stated interest payments, if any, due on such senior secured convertible notes on each interest payment date occurring after the conversion date for such conversion and on or before June 1, 2023. In addition, we will have the right to cause all senior secured convertible notes then outstanding to be converted automatically if the volume-weighted average price per share of our common stock equals or exceeds 130% of the conversion price for a specified period of time and certain other conditions are satisfied.

Holders of the senior secured convertible notes will have the right, at their option, to require us to purchase their senior secured convertible notes if a fundamental change (as defined in the indenture) occurs, in each case, at a repurchase price equal to 100% of the principal amount of the senior secured convertible notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the applicable repurchase date.

Notwithstanding the foregoing, our ability to settle conversions and make interest payments using shares of our common stock is subject to certain limitations set forth in the indenture until such time, if any, that our stockholders have approved an amendment to our certificate of incorporation to increase the number of authorized shares. We intend to seek approval of this matter at a special meeting of stockholders.

Subject to a number of exceptions and qualifications, the indenture restricts our ability and the ability of certain of our subsidiaries to, among other things, pay dividends or make other payments or distributions on capital stock, or purchase, redeem, defease or otherwise acquire or retire for value any capital stock, (ii) make certain investments, (iii) incur indebtedness or issue preferred stock, other than certain forms of permitted debt, which includes, among other items, indebtedness incurred to refinance the 2021 notes, (iv) create liens on assets, (v) sell assets, (vi) enter into certain transactions with affiliates or (vii) merge, consolidate or sell of all or substantially all assets. The indenture also requires us to make an offer to repurchase the senior secured convertible notes upon the occurrence of certain asset sales.

The indenture provides that a number of events will constitute an event of default, including, among other things, (i) a failure to pay interest for 30 days, (ii) failure to pay the senior secured convertible notes when due at maturity, upon any required repurchase, upon declaration of acceleration or otherwise, (iii) failure to convert the senior secured convertible notes in accordance with the indenture and the failure continues for five business days, (iv) not issuing certain notices required by the indenture within a timely manner, (v) failure to comply with the other covenants or agreements in the indenture for 60 days following the receipt of a notice of non-compliance, (vi) a default or other failure by us to make required payments under other indebtedness of us or certain subsidiaries having an outstanding principal amount of $30.0 million or more, (vii) failure by us or certain subsidiaries to pay final judgments aggregating in excess of $30.0 million, (viii) certain events of bankruptcy or insolvency and (ix) the commercial launch in the United States of a product determined by the United States Food and Drug Administration to be bioequivalent to Inbrija. In the case of an event of default arising from certain events of bankruptcy or insolvency with respect to us, all outstanding senior secured convertible notes will become due and payable immediately without further action or notice. If any other event of default occurs and is continuing, the trustee or the holders of at least 25% in aggregate principal amount of the then outstanding senior secured convertible notes may declare all the notes to be due and payable immediately.

The 2021 notes received by the Company in the exchange were cancelled in accordance with their terms. Upon completion of the exchange, $69.0 million of 2021 notes remain outstanding.

On December 20, 2019, we also entered into a registration rights agreement with the holders participating in the exchange, pursuant to which we filed a Registration Statement on Form S-3 on January 15, 2020 (File No. 333-235929), which became effective on January 24, 2020, following the issuance of the senior secured convertible notes to register the resale of the shares of up to 9,598,979 shares of common stock issuable with respect to the senior secured convertible notes.

Under the registration rights agreement, we also agreed to file a registration statement within 10 business days following the date our stockholders approve the issuance of more than 19.99% of our outstanding shares in accordance with Nasdaq listing standards. On June 15, 2020, our stockholders approved such issuance above 19.99% of our outstanding shares. The registration statement of which this prospectus is a part registers the resale of those shares of common stock issuable with respect to the senior secured convertible notes in excess of the 9,598,979 shares registered with the January 15, 2020 registration statement. Notwithstanding the foregoing, the maximum number of shares that may be resold under this prospectus is 8,698,049, which, together with the 9,598,979 shares of common stock registered in January 2020, is the maximum number of shares that we may issue to settle conversions or make interest payments until the time, if any, that our stockholders have approved an amendment to our certificate of incorporation to increase the number of authorized shares.

Under the registration rights agreement, we agreed to use reasonable best efforts to cause the registration of all shares of common stock issuable with respect to the senior secured convertible notes to become effective and to thereafter maintain the effectiveness of such registration statements. The registration rights agreement includes customary indemnification rights in connection with the registration statements. The registration statement of which this prospectus is a part has been filed in accordance with the registration rights agreement.

SELLING STOCKHOLDERS

The shares of common stock being offered by the selling stockholders are those issuable to the selling stockholders upon conversion of or payment of interest with respect to the senior secured convertible notes. For additional information regarding the issuance of the senior secured convertible notes, see “Private Exchange of Convertible Notes” above. We are registering the shares of common stock in order to permit the selling stockholders to offer the shares for resale from time to time. Except for the ownership of the senior secured convertible notes and the 2021 notes, the selling stockholders have not had any material relationship with us within the past three years.

The table below lists the selling stockholders and other information regarding the beneficial ownership of the shares of common stock by each of the selling stockholders. The second column lists the number of shares of common stock beneficially owned by each selling stockholder, based on its ownership of the shares of common stock and the senior secured convertible notes, as of May 31, 2020, assuming full conversion of the senior secured convertible notes held by the selling stockholders on that date, without regard to any limitation on conversion.

In accordance with the terms of registration rights agreement with the holders of the senior secured convertible notes, this prospectus generally covers the resale of that number of shares of common stock equal to the number of shares of common stock issuable upon conversion of the related senior secured convertible notes, determined as if the outstanding senior secured convertible notes were converted, as applicable, in full (including the interest make-whole payment that would apply if the conversion had occurred on such date), in each case as of the trading day immediately preceding the date the registration statement of which this prospectus forms a part was initially filed with the SEC, less amounts that were previously registered for resale. Notwithstanding the foregoing, the maximum number of shares that may be resold under this prospectus is 8,698,049, which, together with the 9,598,979 shares of common stock registered in January 2020, is the maximum number of shares that we may issue to settle conversions or make interest payments until the time, if any, that our stockholders have approved an amendment to our certificate of incorporation to increase the number of authorized shares.

The amount listed in the third column reflects the number of shares being offered by each selling stockholder and the amount listed in the fourth column reflects the number of shares remaining following the sale of such shares and those that were previously registered for resale. The amounts listed do not assume sales by any other selling stockholder and are subject to the maximum number of shares that may be resold under this prospectus.

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PLAN OF DISTRIBUTION

We are registering the shares of common stock issuable upon conversion of or payment of interest with respect to the senior secured convertible notes to permit the resale of these shares of common stock by the holders from time to time after the date of this prospectus. We will not receive any of the proceeds from the sale by the selling stockholders of the shares of common stock. We will bear all fees and expenses incident to our obligation to register the shares of common stock.

The selling stockholders may sell securities under this prospectus in public offerings:

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all or a portion of the shares of common stock beneficially owned by them and offered hereby from time to time directly or through one or more underwriters, broker-dealers or dealers



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agents. If the shares of common stock are sold through other agents;underwriters or



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directly to purchasers.

        The securities that we or any of broker-dealers, the selling stockholders may sell under this prospectuswill be responsible for underwriting discounts or commissions or agent’s commissions. The shares of common stock may be priced:

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at a fixed public offering price or prices, which may be changed from time to time;



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at market prices prevailing at the times of sale;



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at prices calculated by a formula based on prevailing market prices;



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at negotiated prices; or



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in a combination of any of the above pricing methods.

        If we or any of the selling stockholders use underwriters for an offering, they will acquire securities for their own account and may resell them from time to timesold in one or more transactions at a fixed public offering price orprices, at prevailing market prices at the time of the sale, at varying prices determined at the time of sale. The obligationssale, or at negotiated prices. These sales may be effected in transactions, which may involve crosses or block transactions,

If the selling stockholders effect such transactions by selling shares of common stock to or through underwriters, to purchase the securities will be subject to the conditions set forthbroker-dealers or agents, such underwriters, broker-dealers or agents may receive commissions in the applicable underwriting agreement. Weform of discounts, concessions or anycommissions from the selling stockholders or commissions from purchasers of the shares of common stock for whom they may act as agent or to whom they may sell as principal (which discounts, concessions or commissions as to particular underwriters, broker-dealers or agents may be in excess of those customary in the types of transactions involved). In connection with sales of the shares of common stock or otherwise, the selling stockholders may enter into hedging transactions with broker-dealers, which may in turn engage in short

sales of the shares of common stock in the course of hedging in positions they assume. The selling stockholders may also sell shares of common stock short and deliver shares of common stock covered by this prospectus to close out short positions and to return borrowed shares in connection with such short sales. The selling stockholders may also loan or pledge shares of common stock to broker-dealers that in turn may sell such shares.

The selling stockholders may pledge or grant a security interest in some or all of the senior secured convertible notes or shares of common stock owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the securitiesshares of common stock from time to time pursuant to this prospectus or any amendment or supplement to this prospectus under Rule 424(b)(3) or other applicable provision of the public through underwriting syndicates represented by managing underwritersSecurities Act of 1933, as amended, amending, if necessary, the list of selling stockholders to include the pledgee, transferee or by underwriters without a syndicate. Subject to certain conditions,other successors in interest as selling stockholders under this prospectus. The selling stockholders also may transfer and donate the underwritersshares of common stock in other circumstances in which case the transferees, donees, pledgees or other successors in interest will be obligated to purchase all the securities offered by the prospectus supplement. selling beneficial owners for purposes of this prospectus.

The public offering priceselling stockholders and any broker-dealer participating in the distribution of the shares of common stock may be deemed to be “underwriters” within the meaning of the Securities Act, and any commission paid, or any discounts or concessions allowed to, any such broker-dealer may be deemed to be underwriting commissions or discounts under the Securities Act. At the time a particular offering of the shares of common stock is made, a prospectus supplement, if required, will be distributed which will set forth the aggregate amount of shares of common stock being offered and the terms of the offering, including the name or names of any broker-dealers or agents, any discounts, commissions and other terms constituting compensation from the selling stockholders and any discounts, commissions or concessions allowed or reallowed or paid to dealersbroker-dealers.

Under the securities laws of some states, the shares of common stock may changebe sold in such states only through registered or licensed brokers or dealers. In addition, in some states the shares of common stock may not be sold unless such shares have been registered or qualified for sale in such state or an exemption from time to time. Only underwriters named in a prospectus supplement are underwritersregistration or qualification is available and is complied with.

There can be no assurance that any selling stockholder will sell any or all of the securities offered by that prospectus supplement.

        If thisshares of common stock registered pursuant to the registration statement is used for an "atof which this prospectus forms a part.

The selling stockholders and any other person participating in such distribution will be subject to applicable provisions of the market offering"Securities Exchange Act of 1934, as definedamended, and the rules and regulations thereunder, including, without limitation, Regulation M of the Securities Exchange Act of 1934, as amended, which may limit the timing of purchases and sales of any of the shares of common stock by the selling stockholders and any other participating person. Regulation M may also restrict the ability of any person engaged in Rule 415(a)(4)the distribution of the shares of common stock to engage in market-making activities with respect to the shares of common stock. All of the foregoing may affect the marketability of the shares of common stock and the ability of any person or entity to engage in market-making activities with respect to the shares of common stock.

We will pay all expenses of the registration of the shares of common stock pursuant to the registration rights agreement, estimated to be approximately $61,000 in total, including, without limitation, Securities and Exchange Commission filing fees and expenses of compliance with state securities or “blue sky” laws; provided, however, that a selling stockholder will pay all underwriting discounts and selling commissions, if any. We will indemnify the selling stockholders against liabilities, including some liabilities under the Securities Act, in accordance with the amount of securities registered under this registration statement for such an offering may not exceed 10% of the aggregate market value of our outstanding voting stock as proscribed by Rule 415(a)(4) of the Securities Act.

        Werights agreements, or any of the selling stockholders will be entitled to contribution. We may also sell securities directly or through agents. We or any such selling stockholders will name any agent involved in an offering and we or any such selling stockholders will describe any commissions we or any such selling stockholders will pay the agent in the applicable prospectus supplement. Unless the prospectus supplement states otherwise, our or the applicable selling stockholder's agents will act on a best-efforts basis.

        We or any ofbe indemnified by the selling stockholders may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us or any such selling stockholders at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We or any such selling