As filed with the Securities and Exchange Commission on MayAugust 20, 20152021

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON,Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

OXiGENE, INC.Oncotelic Therapeutics, Inc.

(Exact name of registrantRegistrant as specified in its charter)

701 Gateway Boulevard, Suite 210

South San Francisco, CA 94080

(650) 635-7000

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)Copies to

William D. Schwieterman, M.D.Daniel W. Rumsey, Esq.

President and Chief Executive OfficerJohn P. Kennedy, Esq.

OXiGENE, Inc.Disclosure Law Group, a Professional Corporation

701 Gateway Boulevard,655 West Broadway, Suite 210870

South San Francisco,Diego, CA 9408092101

(650) 635-7000Telephone: (619) 272-7050

(Name, address, including zip code, and telephone number, including area code, of agent for service)Facsimile: (619) 330-2101

With a copy to:

Megan N. Gates, Esq.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

One Financial Center

Boston, Massachusetts 02111

(617) 542-6000

Approximate date of commencement of proposed sale to the public: From time to timepublic: As soon as practicable after the effective date of this registration statement as determined by the registrant.becomes effective.

If the only securities being registered on this Formform are being offered pursuant to dividend or interest reinvestment plans, please check the following box:  ¨box. ☐

If any of the securities being registered on this Formform are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box:   xbox. ☒

If this Formform is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨☐

If this Formform is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨☐

If this Formform is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ¨☐

If this Formform is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ¨☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”filer,” “smaller reporting company,” and “smaller reporting“emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

CALCULATION OF REGISTRATION FEE

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) OF THE SECURITIES ACT OFof the Securities Act of 1933 AS AMENDED, OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SAID SECTIONor until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), MAY DETERMINE.may determine.

ONCOTELIC THERAPEUTICS, INC.

THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. WE MAY NOT SELL THESE SECURITIES UNTIL THE REGISTRATION STATEMENT FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.70,618,065 Shares of Common Stock

SUBJECT TO COMPLETION, DATED MAY 20, 2015

PROSPECTUS

OXIGENE, INC.

$75,000,000

COMMON STOCK

PREFERRED STOCK

DEBT SECURITIES

WARRANTS

RIGHTS

PURCHASE CONTRACTS

UNITS

This prospectus will allow usrelates to issue,the offer and sale of up to 70,618,065 shares of Common Stock of Oncotelic Therapeutics, Inc., a Delaware corporation (the “Company”) by the selling stockholders identified herein. The shares of Common Stock being registered hereunder (the “Shares”) include 42,737,500 shares of Common Stock issuable upon exercise of common stock purchase warrants (the “Warrants”), 4,000,000 shares of Common Stock issuable upon conversion of convertible debentures (the “Debentures”), and 23,880,565 shares of Common Stock issuable upon conversion of convertible notes (the “Notes”) held by the selling stockholders. The Warrants, Debentures and Notes were issued by the Company to the selling stockholders in various transactions that occurred from time to time at pricesbetween April 2018 and on terms to be determined at or prior toAugust 2021 (the “Equity Transactions”). See the timesection titled The Corporate Equity Transactions in this prospectus for a description of these Equity Transactions.

We are not selling any securities under this prospectus and will not receive any of the offering, up to $75,000,000proceeds from the sale of any combinationshares by the selling stockholder, but we will receive proceeds from the exercise of the securitiesWarrants, if exercised in cash.

The selling stockholders may sell the shares of Common Stock described in this prospectus either individuallyin a number of different ways, and the prices at which the selling stockholders may sell the shares will be determined by the prevailing market price for the shares or in units.negotiated transactions. We may also offer common stock or preferred stock upon conversion of or exchange forwill bear the debt securities; common stock upon conversion of or exchange forcosts relating to the preferred stock; common stock, preferred stock or debt securities upon the exercise of warrants, rights or performance of purchase contracts; or any combinationregistration of these securities uponshares. See Plan of Distribution for more information about how the performance of purchase contracts.

The market value of our outstanding common equity held by non-affiliates on May 12, 2015 was approximately $37,122,000, based on 26,544,934selling stockholders may sell the shares of outstanding common stock, of which 26,515,810 are held by non-affiliates, and a per share price of $1.40 basedCommon Stock being registered pursuant to this prospectus.

Our Common Stock is currently listed on the closing sale price of our common stock on May 12, 2015. As of the date of this prospectus, we have sold securities in an aggregate offering amount of $16,000,009.00 pursuant to General Instruction I.B.6. of Form S-3 during the 12 calendar month period that ends on, and includes, the date of this prospectus.

This prospectus describes the general terms of these securities and the general manner in which these securities will be offered. We will provide you with the specific terms of any offering in one or more supplements to this prospectus. The prospectus supplements will also describe the specific manner in which these securities will be offered and may also supplement, update or amend information contained in this document. You should read this prospectus and any prospectus supplement, as well as any documents incorporated by reference into this prospectus or any prospectus supplement, carefully before you invest.

Our securities may be sold directly by us to you, through agents designated from time to time or to or through underwriters or dealers. For additional information on the methods of sale, you should refer to the section entitled “Plan of Distribution” in this prospectus and in the applicable prospectus supplement. If any underwriters or agents are involved in the sale of our securities with respect to which this prospectus is being delivered, the names of such underwriters or agents and any applicable fees, commissions or discounts and over-allotment options will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds that we expect to receive from such sale will also be set forth in a prospectus supplement.

Our common stock is listed on The Nasdaq CapitalOTCQB Market under the symbol “OXGN.”“OTLC”. On May 12, 2015,August 20, 2021, the last reported sale price of our common stockCommon Stock was $1.40$0.13 per share. The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on The Nasdaq Capital Market or any securities market or other securities exchange of the securities covered by the prospectus supplement. Prospective purchasers of our securities are urged to obtain current information as to the market prices of our securities, where applicable.

Investing in our securitiesCommon Stock involves a high degree of risk. Before deciding whether to invest in our securities, youYou should considerreview carefully the risks that we haveand uncertainties described under “Risk Factors” beginning on page 115 of this prospectus, and under the caption “Risk Factors.” We may include specific risk factorssimilar headings in any amendments or supplements to this prospectus under the caption “Risk Factors.” This prospectus may not be used to sell our securities unless accompanied by a prospectus supplement.prospectus.

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

The date of this prospectus is MayAugust 20, 2015.

TABLE OF CONTENTS

RISK FACTORS

Our Annual Report on Form 10-K for the fiscal year ended December 31, 2020 and our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2021 and June 30, 2021, which are incorporated by reference into this prospectus, as well as our other filings with the SEC, include material risk factors relating to our business. Those risks and uncertainties are not the only risks and uncertainties that we face. Additional risks and uncertainties that are not presently known to us or that we currently deem immaterial or that are not specific to us, such as general economic conditions, may also materially and adversely affect our business and operations.

RATIO OF EARNINGS TO FIXED CHARGES

If any debtof those risks and uncertainties actually occur, our business, financial condition or results of operations could be harmed substantially. In such a case, you may lose all or part of your investment. You should carefully consider the risks and uncertainties described below and incorporated by reference herein, and all other information contained in or incorporated by reference into this prospectus, as updated by our subsequent filings under the Exchange Act, before making an investment decision with respect to our Common Stock.

Risks Related to this Offering

The price of our Common Stock is volatile, and is likely to continue to fluctuate due to reasons beyond our control; a limited public trading market may cause volatility in the price of our Common Stock.

The market price of our Common Stock has been, and likely will continue to be, highly volatile. Factors, including our financial results or our competitors’ financial results, clinical trial and research development announcements and government regulatory action affecting our potential products in both the United States and foreign countries, have had, and may continue to have, a significant effect on our results of operations and on the market price of our Common Stock. We cannot assure you that an investment in our Common Stock will not fluctuate significantly. One or more of these factors could significantly harm our business and cause a decline in the price of our Common Stock in the public market. Substantially all of the shares of our Common Stock issuable upon exercise of outstanding options and warrants have been registered or are likely to be registered for resale or are available for sale pursuant to Rule 144 under the Securities Act, and may be sold from time to time. As of August 10, 2021, we had approximately 371,354,911 shares of Common Stock underlying currently outstanding warrants and options. Sales of any of these shares on the market, as well as future sales of our Common Stock by existing stockholders, or the perception that sales may occur at any time, could adversely affect the market price of our Common Stock.

Our Common Stock is currently quoted on the OTCQB Market. The quotation of our Common Stock on the OTCQB Market does not assure that a meaningful, consistent and liquid trading market currently exists, and in recent years such market has experienced extreme price and volume fluctuations that have particularly affected the market prices of many smaller companies like us. Our Common Stock is subject to this volatility. Sales of substantial amounts of Common Stock, or the perception that such sales might occur, could adversely affect prevailing market prices of our Common Stock and our stock price may decline substantially in a short time and our stockholders could suffer losses or be unable to liquidate their holdings.

Our Common Stock is currently subject to the “Penny Stock” Rules of the SEC and the trading market in our securities is limited, which makes transactions in our stock cumbersome and may reduce the value of an investment in our stock.

As of June 30, 2021, we had net tangible assets of less than $0.7 million and our Common Stock had a market price per share of less than $5.00. As a result, transactions in our Common Stock are subject to the SEC’s “penny stock” rules. The designation of our Common Stock as a “penny stock” likely limits the liquidity of our Common Stock. Prices for penny stocks are often not available to buyers and sellers and the market may be very limited. Penny stocks are among the riskiest equity investments. Broker-dealers who sell penny stocks must provide purchasers of these stocks with a standardized risk-disclosure document prepared by the SEC. The document provides information about penny stocks and the nature and level of risks involved in investing in the penny stock market. A broker must also provide purchasers with bid and offer quotations and information regarding broker and salesperson compensation and make a written determination that the penny stock is a suitable investment for the purchaser and obtain the purchaser’s written agreement to the purchase. Many brokers choose not to participate in penny stock transactions. Because of the penny stock rules, there may be less trading activity in penny stocks. Because shares of our Common Stock are currently subject to these penny stock rules, your ability to trade or dispose of shares of our Common Stock may be adversely affected.

We may not be able to achieve secondary trading of our stock in certain states because our Common Stock is no longer nationally traded, which could subject our stockholders to significant restrictions and costs.

Our Common Stock is not currently eligible for trading on the Nasdaq Capital Market or on a national securities exchange. Therefore, our Common Stock is subject to the securities laws of the various states and jurisdictions of the United States in addition to federal securities law. While we may register our Common Stock or qualify for exemptions for our Common Stock in one of more states, if we fail to do so the investors in those states where we have not taken such steps may not be allowed to purchase our stock or those who presently hold our stock may not be able to resell their shares without substantial effort and expense. These restrictions and potential costs could be significant burdens on our stockholders.

Issuance of additional equity securities may adversely affect the market price of our Common Stock.

We were authorized to issue up to 750,000,000 shares of our Common Stock. As of August 10, 2021, we had 371,354,911 shares of Common Stock issued and outstanding, including 1,019,303 shares of Common Stock to be issued. As of August 10, 2021, we also had approximately 42,737,500 warrants outstanding, approximately 9,444,062 options and approximately 23,880,565 shares of Common Stock issuable upon conversion of convertible notes. To the extent that additional shares of Common Stock are issued or options and warrants are exercised, holders of our Common Stock will experience dilution. In addition, in the event of any future issuances of equity securities or securities convertible into or exchangeable for Common Stock, holders of our Common Stock may experience dilution.

We are also currently authorized to issue up to 15,000,000 shares of preferred stock. As of August 10, 2021, we had no shares of preferred stock outstanding. Our Board of Directors is authorized to issue preferred stock without any action on the part of our stockholders. Our Board of Directors also has the power, without stockholder approval, to set the terms of any such preferred stock that may be issued, including voting rights, conversion rights, dividend rights, preferences over our Common Stock with respect to dividends or if we liquidate, dissolve or wind up our business and other terms. If we issue preferred stock in the future that has preference over our Common Stock with respect to the payment of dividends or upon our liquidation, dissolution or winding up, or if we issue preferred stock with voting rights that dilute the voting power of our Common Stock, the market price of our Common Stock could decrease. Any provision permitting the conversion of any such preferred stock into our Common Stock could result in significant dilution to the holders of our Common Stock.

We also consider from time to time various strategic alternatives that could involve issuances of additional common or preferred stock, are offered pursuantincluding but not limited to this prospectus, we will provide a table setting forth our ratio of earningsacquisitions and business combinations.

We have no plans to fixed charges or ratio of combined fixed charges and preferred stockpay dividends on a historical basisour Common Stock, and you may not receive funds without selling your Common Stock.

We have not declared or paid any cash dividends on our Common Stock, nor do we expect to pay any cash dividends on our Common Stock for the foreseeable future. We currently intend to retain any future earnings, if any, to finance our operations and growth and, potentially, for future stock repurchases and, therefore, we have no plans to pay cash dividends on our Common Stock. Any future determination to pay cash dividends on our Common Stock will be at the discretion of our Board of Directors and will be dependent on our earnings, financial condition, operating results, capital requirements, any contractual restrictions, and other factors that our board of directors deems relevant.

Accordingly, you may have to sell some or all of your Common Stock in order to generate cash from your investment in the applicable prospectus supplement, if required.

SPECIAL NOTECAUTIONARY NOTES REGARDING FORWARD-LOOKING STATEMENTS

The SEC encourages companies to disclose forward-looking information so that investors can better understand a company’s future prospects and make informed investment decisions. This prospectus andcontained in this Prospectus, including in the documents we have filed with the SECincorporated by reference into this Prospectus, includes some statements that are incorporated herein by reference contain suchnot purely historical and that are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995.

statements.” Such statements in connection with any discussion of future operations or financial performance are identified by terminology such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “project,” “contemplate,” “believe,” “estimate,” “potential,” “indicate,” or “continue” or the negative of these terms or other similar words, although not all forward-looking statements contain these words. Forward-looking statements include, but are not limited to, statements regarding our or our management’s expectations, hopes, beliefs, intentions and/or strategies regarding the future, such asincluding our estimates regarding anticipated operating losses, future performance, future revenues and projected expenses; our liquidity and our expectations regarding our needs for and ability to raise additional capital; our ability to manage our expenses effectively and raise the funds needed to continue our business; our ability to retain the services of our current executive officers, directors and principal consultants; the competitive nature of our industry and the possibility that our products or product candidates may become obsolete; our ability to obtain and maintain regulatory approval of our existing products and any future products we may develop; our ability to expand our commercial operations; the clinical development of and the process of commercializing fosbretabulin tromethamine; the clinical development of and the process of commercializing OXi4503, the initiation, timing, progressfinancial condition and results of our preclinicaloperations. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipates,” “believes,” “continue,” “could,” “estimates,” “expects,” “intends,” “may,” “might,” “plans,” “possible,” “potential,” “predicts,” “projects,” “seeks,” “should,” “would” and clinical trials, researchsimilar expressions, or the negatives of such terms, may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking.

The forward-looking statements contained in this Prospectus are based on current expectations and development programs; regulatorybeliefs concerning future developments and legislativethe potential effects on the parties and the transaction. There can be no assurance that future developments actually affecting us will be those anticipated. These that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements, including the following forward-looking statements involve a number of risks, uncertainties (some of which are beyond the parties’ control) or other assumptions.

THE CORPORATE EQUITY TRANSACTIONS

The Company has financed its operations, in part, through the issuance and sale of equity and debt securities, including the issuance of the Warrants, Debentures and Notes. Information about the transactions resulting in the United Statesissuance of the Warrants and foreign countries;Notes follows below:

April 2018 Warrants

On April 12, 2018, we entered into subscription agreements certain investors in connection with the timing, costssale of an aggregate of 59.5 units (the “2018 Units”), at a purchase price of $50,000 per 2018 Unit. The 2018 Units were sold as part of a private placement (the “2018 Private Placement”). Each 2018 Unit consisted of 250,000 shares of Common Stock, Series A Warrants to purchase up to 125,000 shares of Common Stock at an exercise price of $0.20 per share, and other limitations involved in obtaining regulatory approval for any product;Series B Warrants to purchase up to 125,000 shares of Common Stock at an exercise price of $0.20 per share (the “2018 Warrants”). The estimated net proceeds from the further preclinical or clinical development2018 Private Placement were $2.4 million.

In February 2020, the Company offered to cancel the 2018 Warrants and commercializationto reissue new warrants with an exercise price of our product candidates; the potential benefits$0.20 per share (the “Reissue Warrants”) to such warrant holders. Holders of our product candidates over other therapies; our ability15,237,500 warrants opted to enter into any collaboration with respect to product candidates; our ability to continue to develop or commercialize our products or product candidatesparticipate in the event any license agreements in place with third parties expire or are terminated; the performance of third parties, including our third-party manufacturers; our ability to obtain and maintain intellectual property protection for our products and operate our business without infringing upon the intellectual property rights of others; the potential liability exposure related to our products and our insurance coverage for such exposure; the successful development of our sales and marketing capabilities; the size and growthreissuance. All other terms of the potential markets for our products and our ability to serve those markets;Reissue Warrants remained the rate and degreesame as the 2018 Warrants.

An aggregate of market acceptance15,237,500 shares of any future products; the potential for provisions set forth in our certificate of incorporation or amended and restated bylaws to deter potential acquisition offers; the volatilityCommon Stock issuable upon conversion of the price of our common stock; our ability to maintain an effective system of internal controls; the payment and reimbursement methods used by private or governmental third-party payers; and other factors detailed under the heading “Risk Factors”2020 Reissue Warrants are included in this prospectus as updated and supplementedbeing registered hereunder. If all of the 2020 Reissue Warrants are exercised for cash, we will receive gross proceeds of $3,047,500.

April 2019 Convertible Debentures

On April 17, 2019, the Company entered into a Securities Purchase Agreement (the “Bridge SPA”) with the Vuong Trieu, Ph. D., the Chief Executive Officer of the Company, and another investor (the “Bridge Investor”) with a commitment to purchase convertible notes in the aggregate of $400,000.

On April 23, 2019, the Company entered into a convertible note with Vuong Trieu, Ph. D. (the “Trieu Note”). The Trieu Note has a principal balance of $164,444, including a 10% OID of $16,444, resulting in net proceeds of $148,000, with a maturity date of April 23, 2022. Upon the occurrence of certain events of default, the Buyer, amongst other remedies, has the right to charge a penalty in a range of 18% to 40% dependent on the specific default event. Amounts due under the Convertible Note may also be converted into shares (the “Trieu Conversion Shares”) of the Company’s Common Stock at any time, at the option of the holder, at a conversion price of $0.10 per share (the “Fixed Price”), at the lower of the Fixed Price or 65% of the Company’s lowest traded price after the 180^th day or at the lower of the Fixed Price or 55% of the Company’s traded stock price under certain circumstances. The Company has agreed to, at all times, reserve and keep available out of its authorized Common Stock a number of shares equal to at least two times the full number of Conversion Shares. The Company may redeem the Convertible Note at rates of 110% to 140% rates over the principal balance dependent on certain events and redeem the value with accrued interest thereon, if any.

On April 23, 2019, pursuant to the Bridge SPA the Company entered into Convertible Note Tranche #1 (“Tranche #1”) with the Bridge Investor. Tranche #1 has a principal balance of $35,556, an OID of $3,556, resulting in net proceeds of $32,000, with a maturity date of April 23, 2022. Upon the occurrence of certain events of default, the Buyer, among other remedies, has the right to charge a penalty in a range of 18% to 40% dependent on the specific default event. Amounts due under Tranche #1 may also be converted into shares (the “Bridge SPA Conversion Shares”) of the Company’s Common Stock at any time, at (i) a conversion price, during the first 180 days, of $0.10 per share (the “Fixed Price”), and then (2) at the lower of the Fixed Price or 65% of the Company’s lowest traded price after the first 180 days or at the lower of the Fixed Price or 55% of the Company’s traded stock price under certain circumstances. The Company may redeem the Convertible Note at rates of 110% to 140% rates over the principal balance dependent on certain events and redeem the value with accrued interest thereon, if any.

On August 6, 2019, pursuant to the Bridge SPA the Company entered into Convertible Note Tranche #2 (“Tranche #2”, and together with the Trieu Note and Tranche #1, the “April 2019 Convertible Debentures”) with the Bridge Investor. Tranche #2 has a principal balance of $200,000, an OID of $20,000 and debt issuance costs of $5,000, resulting in net proceeds of $175,000, with a maturity date of August 6, 2022. Upon the occurrence of certain events of default, the Buyer, among other remedies, has the right to charge a penalty in a range of 18% to 40% dependent on the specific default event. Amounts due under Tranche #1 may also be converted into Bridge Conversion Shares of the Company’s Common Stock at any time, at the option of the holder, at a conversion price equal to the Fixed Price, at the lower of the Fixed Price or 65% of the Company’s lowest traded price after the 180^th day or at the lower of the Fixed Price or 55% of the Company’s traded stock price under certain circumstances. The Company may redeem the Convertible Note at rates of 110% to 140% rates over the principal balance dependent on certain events and redeem the value with accrued interest thereon, if any.

The April 2019 Bridge Notes reached the 180 days prior to the end of the three months ended March 31, 2020. As such, all the note holders had the ability to convert that debt into equity at the variable conversion price of 65% of the Company’s lowest traded price after the first 180 days or at the lower of the Fixed Price or 55% of the Company’s traded stock price under certain circumstances.

An aggregate of 4,000,000 shares of Common Stock issuable upon conversion of the April 2019 Convertible Debentures are included in this prospectus and being registered hereunder.

Fall 2019 Convertible Notes

In December 2019, the Company entered into Note Purchase Agreements (the “Note Purchase Agreements”) with certain accredited investors for the sale of convertible promissory notes (the “Fall 2019 Convertible Notes”) raising an additional $500,000 for gross proceeds of $1.0 million (the “Fall 2019 Debt Financing”). The Company also offset certain amounts due to Dr. Vuong Trieu, the Company’s Chief Executive Officer, Chulho Park, the Company’s Chief Technology Officer, and Amit Shah, the Company’s Chief Financial Officer and converted such amounts due into the Fall 2019 Convertible Notes, including $35,000 due to Dr. Vuong Trieu, $27,000 due to Chulho Park and $20,000 due to Amit Shah.

The Fall 2019 Convertible Notes provide for interest at the rate of 5% per annum and are unsecured. All amounts outstanding under the Fall 2019 Convertible Notes become due and payable upon the approval of the holders of a majority of the principal amount of outstanding Fall 2019 Convertible Notes (the “Majority Holders”) on or after (a) November 23, 2020 or (b) the occurrence of an event of default (either, the “Maturity Date”). The Company may prepay the Fall 2019 Convertible Notes at any time. Events of default under the Fall 2019 Convertible Notes include failure to make payments under the Fall 2019 Convertible Notes within thirty (30) days of the date due, failure to observe of the Note Purchase Agreement or Fall 2019 Convertible Notes which is not cured within thirty (30) days of notice of the breach, bankruptcy, or a change in control of the Company (as defined in the Note Purchase Agreement).

The Majority Holders have the right, at any time not more than five (5) days following the Maturity Date, to elect to convert all, and not less than all, of the outstanding accrued and unpaid interest and principal on the Fall 2019 Convertible Notes. The Fall 2019 Convertible Notes may be converted, at the election of the Majority Holders, either (a) into shares of the Company’s Common Stock at a conversion price of $0.18 per share, or (b) into shares of common stock of the Edgepoint, at a conversion price of $5.00 (based on a $5.0 million pre-money valuation) of Edgepoint and 1,000,000 shares outstanding.

An aggregate of 4,722,222 shares of Common Stock issuable upon conversion of the Fall 2019 Convertible Notes are included in this prospectus and being registered hereunder.

July 2020 to March 2021 Convertible Notes and Warrants - Private Placement through JH Darbie & Co., Inc.

Between July 2020 and March 2021, the Company offered and sold certain units (“JHD Units”) in a private placement (“PPM”) through JH Darbie & Co., Inc. (“JH Darbie”), with each unit consisting of: (i) 25,000 shares of Edgepoint common stock, par value $0.01 per share (“Edgepoint Common Stock”), for a price of $1.00 per share; (ii) one convertible promissory note issued by the discussionCompany (the “PPM Convertible Note”), convertible into up to 25,000 shares of risksEdgePoint Common Stock at a conversion price of $1.00 per share, or up to 138,889 shares of the Company’s Common Stock, at a conversion price of $0.18 per share; and uncertainties(iii) 300,000 warrants (the “PPM Warrants”), consisting of (a) 50,000 warrants to purchase an equivalent number of shares of EdgePoint Common Stock at $1.00 per share (“Edgepoint Warrant”), and (b) 250,000 warrants to purchase an equivalent number of shares of Company Common Stock at $0.20 per share (the “JH Darbie Financing”).

Between July 2020 and March 2021, the Company issued and sold a total of 100 JHD Units, and 10 JHD Units were issued to JH Darbie as fees. The JH Darbie Financing resulted in gross proceeds of $5 million to the Company. Placement agent fees of $0.65 million were paid to JH Darbie pursuant to that certain Placement Agent Agreement, dated February 25, 2020 between the Company and JH Darbie (the “Darbie Placement Agreement”).

An aggregate of 15,277,787 shares of Common Stock issuable upon conversion of PPM Convertible Notes issued in the JH Darbie Financing and 27,500,000 shares of Common Stock issuable upon exercise of PPM Warrants are included in this prospectus and being registered hereunder. If all of the PPM Warrants are exercised for cash, we will receive gross proceeds of $5,500,000.

August 2021 Debt Financing

On August 4, 2021, the Company entered into Note Purchase Agreements (collectively, the “2021 Note Purchase Agreements”) with (i) Autotelic Inc., an entity in which Dr. Vuong Trieu, the Company’s Chairman and Chief Executive Officer, is also the Chief Executive Officer, (ii) Amit Shah, the Chief Financial Officer of the Company, and (iii) certain other accredited investors. Under the terms of the 2021 Note Purchase Agreements, the Company issued an aggregate of $698,500 (the “Principal Amount”) in debt in the form of unsecured convertible promissory notes (collectively, the “Notes”).

The Notes are unsecured, and provide for interest at the rate of 5% per annum. All amounts outstanding under “Risk Factors” containedthe Notes become due and payable at such time as determined by the holders of a majority of the Principal Amount of the Notes (the “Majority Holders”), on or after (a) the one year anniversary of the Notes ,or (b) the occurrence of an Event of Default (as defined in the Note Purchase Agreements) (the “Maturity Date”). The Company may prepay the Notes at any supplementstime. Events of Default under the Notes include, without limitation, (i) failure to make payments under the Notes within thirty (30) days of the Maturity Date, (ii) breaches of the Note Purchase Agreement or Notes by the Company which is not cured within thirty (30) days of notice of the breach, (iii) bankruptcy, or (iv) a change in control of the Company (as defined in the Note Purchase Agreements).

The Majority Holders have the right, at any time not more than five days following the Maturity Date, to elect to convert all, and not less than all, of the outstanding accrued and unpaid interest and principal on the Notes. The Notes may be converted, at the election of the Majority Holders, into shares of the Company’s common stock, par value $0.01 per share, at a fixed conversion price of $0.18 per share.

An aggregate of 3,880,556 shares of Common Stock issuable upon conversion of the Fall 2019 Convertible Notes are included in this prospectus and being registered hereunder.

SELLING STOCKHOLDERS

This prospectus relates to the resale by the selling stockholders identified in the table below of the shares of Common Stock issuable upon exercise of the Warrants, the Convertible Debentures and the Notes. The selling stockholders may, from time to time, offer and sell pursuant to this prospectus and in our most recent annual report on Form 10-K, as revisedany or supplemented by our subsequent quarterly reports on Form 10-Q or our current reports on Form 8-K, as well as any amendments thereto, as filed with the SEC and which are incorporated herein by reference. The information contained in this document is believed to be current asall of the dateshares of Common Stock acquired upon exercise of the Warrants or conversion of the Convertible Debentures or Notes. The selling stockholders may sell some, all or none of the Shares registered by the registration statement of which this document.prospectus forms a part. We do not intend to updateknow how long the selling stockholders will hold the Shares before selling them or if the selling stockholders will exercise any of the forward-looking statementsWarrants, or convert any of the Notes, and we currently have no agreements, arrangements or understandings with the selling stockholders regarding the sale of any of the Shares. For more information about the transactions pursuant to which the selling stockholders acquired the Warrants, the Convertible Debentures and the Notes, please see the section titled The Corporate Equity Transactions above.

The following table presents information regarding the selling stockholders and the shares of Common Stock issuable upon exercise of the Warrants or conversion of the Convertible Debentures or Notes that they may offer and sell from time to time under this prospectus. The table is prepared based on information supplied to us by the selling stockholders, and reflects its holdings as of August 10, 2021. Unless otherwise indicated below, none of the selling stockholders nor any of their affiliates has held a position or office, or had any other material relationship, with us or any of our predecessors or affiliates. Beneficial ownership is determined in accordance with Section 13(d) of the Exchange Act and Rule 13d-3 thereunder.

USE OF PROCEEDS

The Common Stock to be offered and sold using this prospectus will be offered and sold by the selling stockholders named in this prospectus. Accordingly, we will not receive any proceeds from any sale of shares of our Common Stock in this offering related to the Debentures or various Notes. The shares of Common Stock registered by this prospectus may be issued upon exercise of the Warrants or conversion of the Convertible Debentures or Notes. Upon any exercise of the Warrants, the selling stockholders will pay us the applicable exercise price related to the exercise of the Warrants, and we currently anticipate that any such proceeds would be used primarily for developing our portfolio of drug products, working capital and general corporate purposes. We will pay all of the fees and expenses incurred by us in connection with this registration. We will not be responsible for fees and expenses incurred by the selling stockholders or any underwriting discounts or agent’s commissions.

PLAN OF DISTRIBUTION

We are registering the shares of Common Stock issuable upon exercise of the Warrants and conversion of the Convertible Debentures or Notes held by the selling stockholders identified herein to permit the resale of these shares of Common Stock by the holders thereof from time to time after the date of this document to conform these statements to actual results or to changes in our expectations, except as required by law.

In light of these assumptions, risks and uncertainties, the results and events discussed in the forward-looking statements contained in this prospectus or in any document incorporated herein by reference might not occur. Investors are cautioned not to place undue reliance on the forward-looking statements, which speak only as of the date of this prospectus or the date of the document incorporated by reference in this prospectus. We arewill not under any obligation, and we expressly disclaim any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise. All subsequent forward-looking statements attributable to us or to any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section.

USE OF PROCEEDS

We cannot assure you that we will receive any proceeds in connection with securities which may be offered pursuant to this prospectus. Unless otherwise indicated inof the applicable prospectus supplement, we intend to use any net proceeds from the sale by the selling stockholders of securities under this prospectus forthe shares of our operationsCommon Stock, if any. We will bear all fees and for other general corporate purposes, including, but not limitedexpenses incident to our internal research and development programs andobligation to register the developmentshares of new technologies, general working capital and possible future acquisitions. We have not determined the amounts we plan to spend on any of the areas listed aboveour Common Stock.

The Common Stock may be sold or the timing of these expenditures. As a result, our management will have broad discretion to allocate the net proceeds, if any, we receive in connection with securities offered pursuant to this prospectus for any purpose. Pending application of the net proceeds as described above, we may initially invest the net proceeds in short-term, investment-grade, interest-bearing securities or apply them to the reduction of short-term indebtedness.

PLAN OF DISTRIBUTION

General Plan of Distribution

We may offer securities under this prospectusdistributed from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a combination of these methods. We may sellby the securities (1) through underwriters or dealers, (2) through agents or (3)selling stockholder directly to one or more purchasers or through a combination of such methods. Webrokers, dealers, or underwriters who may distribute the securities from time to time in one or more transactions at:

We may directly solicit offers

In order to purchasecomply with the securities being offered by this prospectus. Welaws of certain states, if applicable, the shares may also designate agents to solicit offers to purchasebe sold only through registered or licensed brokers or dealers. In addition, in certain states, the securities from time to time. We will name in a prospectus supplement any underwritershares may not be sold unless they have been registered or agent involvedqualified for sale in the offerstate or sale ofan exemption from the securities.state’s registration or qualification requirement is available and complied with.

If we utilize a dealer in the saleselling stockholders effect such transactions by selling shares of the securities being offered by this prospectus, we will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

If we utilize an underwriter in the sale of the securities being offered by this prospectus, we will execute an underwriting agreement with the underwriter at the time of sale, and we will provide the name of any underwriter in the prospectus supplement which the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we, or the purchasers of the securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securitiesCommon Stock to or through dealers, and the underwriterunderwriters, broker-dealers or agents, such underwriters, broker-dealers or agents may compensate those dealersreceive commissions in the form of discounts, concessions or commissions.

With respect to underwritten public offerings, negotiated transactions and block trades, we will provide incommissions from the applicable prospectus supplement information regarding any compensation we pay to underwriters, dealersselling stockholders or agents in connection with the offeringcommissions from purchasers of the securities, and anyshares of Common Stock for whom they may act as agent or to whom they may sell as principal (which discounts, concessions or commissions allowedas 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 our 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 underwritersthis prospectus to participating dealers. Underwriters, dealersclose out short positions and agentsto 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 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 shares of Common Stock from time to time pursuant to this prospectus or any amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act, amending, if necessary, the list of selling stockholders to include the pledgee, transferee or other successors in interest as selling stockholders under this prospectus. The selling stockholders also may transfer and donate the shares of Common Stock in other circumstances in which case the transferees, donees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

The selling stockholders and any broker-dealer participating in the distribution of the securitiesshares of Common Stock may be deemed to be underwriters“underwriters” within the meaning of the Securities Act, of 1933, as amended, or the Securities Act, and any commission paid, or any discounts and commissions received by them andor concessions allowed to, any profit realized by them on resale of the securitiessuch 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 broker-dealers.

Under the securities laws of some states, the shares of Common Stock may be 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 registration or qualification is available and is complied with.

There can be no assurance that any selling stockholder will sell any or all of the shares of Common Stock registered pursuant to the registration statement, of 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 Exchange Act, and the rules and regulations thereunder, including, without limitation, Regulation M of the Exchange Act, 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 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, including, without limitation, SEC 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 commissions.selling commissions, if any. We will indemnify the selling stockholders against liabilities, including some liabilities under the Securities Act, in accordance with the Registration Rights Agreements, or the selling stockholders will be entitled to contribution. We may enter into agreements to indemnify underwriters, dealers and agentsbe indemnified by the selling stockholders against civil liabilities, including liabilities under the Securities Act, that may arise from any written information furnished to us by the selling stockholder specifically for use in this prospectus, in accordance with the related Registration Rights Agreement, or to contribute to payments theywe may be requiredentitled to make in respect thereof.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:contribution.

Shares of our common stock sold pursuant to the registration statement, of which this prospectus isforms a part, the shares of Common Stock will be authorized for quotation and trading on The Nasdaq Capital Market. The applicable prospectus supplement will contain information, where applicable, as to any other listing, if any, on The Nasdaq Capital Market or any securities market or other securities exchange of the securities covered by the prospectus supplement. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

In order to facilitate the offering of the securities, certain persons participatingfreely tradable in the offering may engage in transactions that stabilize, maintain or otherwise affect the pricehands of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securitiesother than we sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing the applicable security in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if the securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.our affiliates.

The underwriters, dealers and agents may engage in other transactions with us, or perform other services for us, in the ordinary course of their business.

DESCRIPTION OF COMMONOUR CAPITAL STOCK

We are authorized to issue 70,000,000 shares of common stock, par value $0.01 per share. On May 12, 2015, we had 26,544,934 shares of common stock outstanding and approximately 44 stockholders of record.

The following summary of certain provisionsthe rights of our common stock does not purport to be complete. You should refer to our restated certificate of incorporation and our amended and restated bylaws, both of which are included as exhibits to the registration statement of which this prospectus is a part. The summary below is also qualified by provisions of applicable law.

General

Holders of common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, and do not have cumulative voting rights. Subject to preferences that may be applicable to any outstanding shares of preferred stock, holders of common stock are entitled to receive ratably such dividends, if any, as may be declared from time to time by our board of directors out of funds legally available for dividend payments. All shares of common stock outstanding as of the date of this prospectus and, upon issuance and sale, all shares of common stock that we may offer pursuant to this prospectus, will be fully paid and nonassessable. The holders of common stock have no preferences or rights of conversion, exchange, pre-emption or other subscription rights. There are no redemption or sinking fund provisions applicable to the common stock. In the event of any liquidation, dissolution or winding-up of our affairs, holders of common stock will be entitled to share ratably in our assets that are remaining after payment or provision for payment of all of our debts and obligations and after liquidation payments to holders of outstanding shares of preferred stock, if any.

Transfer Agent and Registrar

The transfer agent and registrar for our commoncapital stock is American Stock Transfer & Trust Company, LLC.

Nasdaq Capital Market

Our common stock is listed for quotation on The Nasdaq Capital Market under the symbol “OXGN.”

DESCRIPTION OF PREFERRED STOCK

We are authorized to issue 15,000,000 shares of preferred stock, par value $0.01 per share. As of May 12, 2015, no shares of our preferred stock were outstanding and 5,000 shares of Preferred Stock were designated as Series A Convertible Preferred Stock, or Series A Preferred Stock, and 5,800 shares of Preferred Stock were designated as Series B Convertible Preferred Stock, or Series B Preferred Stock. The following summary of certain provisions of our preferred stock does not purport to be complete. You should refer to our restated certificate of incorporation and our amended and restated bylaws, both of which are included as exhibits to the registration statement of which this prospectus is a part and to the applicable certificate of designations for each series of preferred stock. The summary below is also qualified by provisions of applicable law.

General

Our board of directors may, without further action by our stockholders, from time to time, direct the issuance of shares of preferred stock in series and may, at the time of issuance, determine the rights, preferences and limitations of each series, including voting rights, dividend rights and redemption and liquidation preferences. Satisfaction of any dividend preferences of outstanding shares of preferred stock would reduce the amount of funds available for the payment of dividends on shares of our common stock. Holders of shares of preferred stock may be entitled to receive a preference payment in the event of any liquidation, dissolution or winding-up of our company before any payment is made to the holders of shares of our common stock. In some circumstances, the issuance of shares of preferred stock may render more difficult or tend to discourage a merger, tender offer or proxy contest, the assumption of control by a holder of a large block of our securities or the removal of incumbent management. Upon the affirmative vote of our board of directors, without stockholder approval, we may issue shares of preferred stock with voting and conversion rights which could adversely affect the holders of shares of our common stock.

If we offer a specific series of preferred stock under this prospectus, we will describe the terms of the preferred stock in the prospectus supplement for such offering and will file a copy of the certificate establishing the terms of the preferred stock with the SEC. To the extent required, this description will include:

Series A Preferred Stock

On April 11, 2013, we filed the Certificate of Designation of Preferences, Rights and Limitations of Series A Convertible Preferred Stock, or the Series A Certificate of Designation, with the Secretary of State of the State of Delaware, establishing and designating the Series A Preferred Stock. Each share of Series A Preferred Stock has a stated value of $1,000. Each share of Series A Preferred Stock is convertible, at any time at the option of the holder thereof, into a number of shares of Common Stock determined by dividing the stated value by the conversion price of $3.63, subject to the 9.99% ownership limitation described below. The Series A Preferred Stock has no sinking provisions, dividend rights, liquidation preference or other preferences over Common Stock and has no voting rights except as provided in the Series A Certificate of Designation or as otherwise required by law.

The Series A Preferred Stock contains limitations that prevent the holder from acquiring shares upon conversion of shares of Series A Preferred Stock that would result in the number of shares beneficially owned by the holder and its affiliates exceeding 9.99% of the total number of shares of our common stock then issued and outstanding. In addition, upon certain changes in control of OXiGENE, holders of shares of Series A Preferred Stock can elect to receive, subject to certain limitations and assumptions, securities in a successor entity equal to the value of the holders’ Series A Preferred Stock, or if holders of common stock are given a choice of cash or property, then cash or property equal to the value of the holder’s outstanding Series A Preferred Stock.

As of May 12, 2015, no shares of Series A Preferred Stock are outstanding and 5,000 shares of Series A Preferred Stock are available for issuance.

Series B Preferred Stock

On September 19, 2013, we filed the Certificate of Designation of Preferences, Rights and Limitations of Series B Convertible Preferred Stock, or the Series B Certificate of Designation, with the Secretary of State of the State of Delaware, establishing and designating the Series B Preferred Stock. Each share of Series B Preferred Stock has a stated value of $1,000complete and is convertible, at any time at the option of the holder thereof, into a number of shares of our common stock determined by dividing the stated value by the conversion price of $2.365, subject to the 9.99% ownership limitation described below. The Series B Preferred Stock has no sinking provisions, dividend rights, liquidation preference or other preferences over our common stock or the Series A Preferred Stock and has no voting rights except as provided in the Series B Certificate of Designation or as otherwise required by law. There are no redemption or sinking fund provisions applicable to shares of Series B Preferred Stock.

The Series B Preferred Stock contains limitations that prevent the holder from acquiring shares upon conversion of shares of Series B Preferred Stock that would result in the number of shares beneficially owned by the holder and its affiliates exceeding 9.99% of the total number of shares of our common stock then issued and outstanding. In addition, upon certain changes in control of OXiGENE, holders of shares of Series B Preferred Stock can elect to receive, subject to certain limitations and assumptions, securities in a successor entity equal to the value of the holders’ Series B Preferred Stock, or if holders of common stock are given a choice of cash or property, then cash or property equal to the value of the holder’s outstanding Series B Preferred Stock.

As of May 12, 2015, no shares of Series B Preferred Stock are outstanding and 5,800 shares of Series B Preferred Stock are available for issuance.

Transfer Agent and Registrar

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

DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplements, summarizes the material terms and provisions of the 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 pursuant to this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. If we so indicate in a prospectus supplement, the terms of any debt securities offered under such prospectus supplement may differ from the terms we describe below, and to the extent the terms set forth in a prospectus supplement differ from the terms described below, the terms set forth in the prospectus supplement shall control.

We may sell from time to time, in one or more offerings under this prospectus, debt securities, which may be senior or subordinated. We will issue any such senior debt securities under a senior indenture that we will enter into with a trustee to be named in the senior indenture. We will issue any such subordinated debt securities under a subordinated indenture, which we will enter into with a trustee to be named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement, of which this prospectus is a part. We use the term “indentures” to refer to either the senior indenture or the subordinated indenture, as applicable. The indentures will be qualified under the Trust Indenture Act of 1939, as in effect on the date of the indenture. We use the term “debenture trustee” to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to and qualified in theirits entirety by reference to all the provisions of the indenture applicable to a particular series of debt securities.

General

Each indenture provides that debt securities may be issued from time to time in one or more series and may be denominated and payable in foreign currencies or units based on or relating to foreign currencies. Neither indenture limits the amount of debt securities that may be issued thereunder, and each indenture provides that the specific terms of any series of debt securities shall be set forth in, or determined pursuant to, an authorizing resolution and/or a supplemental indenture, if any, relating to such series.

We will describe in each prospectus supplement the following terms relating to a series of debt securities:

We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

Conversion or Exchange Rights

We will set forth in the prospectus supplement the terms, if any, on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale; No Protection in Event of a Change of Control or Highly Leveraged Transaction

The indentures do not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate.

Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions that may afford holders of the debt securities protection in the event we have a change of control or in the event of a highly leveraged transaction (whether or not such transaction results in a change of control), which could adversely affect holders of debt securities.

Events of Default Under the Indenture

The following are events of default under the indentures with respect to any series of debt securities that we may issue:

No event of default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an event of default with respect to any other series of debt securities. The occurrence of an event of default may constitute an event of default under any bank credit agreements we may have in existence from time to time. In addition, the occurrence of certain events of default or an acceleration under the indenture may constitute an event of default under certain of our other indebtedness outstanding from time to time.

If an event of default with respect to debt securities of any series at the time outstanding occurs and is continuing, then the trustee or the holders of not less than a majority in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the debenture trustee if given by the holders), declare to be due and payable immediately the principal (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) of and premium and accrued and unpaid interest, if any, on all debt securities of that series. Before a judgment or decree for payment of the money due has been obtained with respect to debt securities of any series, the holders of a majority in principal amount of the outstanding debt securities of that series (or, at a meeting of holders of such series at which a quorum is present, the holders of a majority in principal amount of the debt securities of such series represented at such meeting) may rescind and annul the acceleration if all events of default, other than the non-payment of accelerated principal, premium, if any, and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the applicable indenture (including payments or deposits in respect of principal, premium or interest that had become due other than as a result of such acceleration). We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an event of default.

Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the debenture trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the debenture trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the debenture trustee, or exercising any trust or power conferred on the debenture trustee, with respect to the debt securities of that series, provided that:

A holder of the debt securities of any series will only have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies if:

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the applicable debenture trustee regarding our compliance with specified covenants in the applicable indenture.

Modification of Indenture; Waiver

The debenture trustee and we may change the applicable indenture without the consent of any holders with respect to specific matters, including:

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the debenture trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series (or, at a meeting of holders of such series at which a quorum is present, the holders of a majority in principal amount of the debt securities of such series represented at such meeting) that is affected. However, the debenture trustee and we may make the following changes only with the consent of each holder of any outstanding debt securities affected:

Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series (or, at a meeting of holders of such series at which a quorum is present, the holders of a majority in principal amount of the debt securities of such series represented at such meeting) may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. The holders of a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of, premium or any interest on any debt security of that series or in respect of a covenant or provision, which cannot be modified or amended without the consent of the holder of each outstanding debt security of the series affected; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration.

Discharge

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for obligations to:

In order to exercise our rights to be discharged with respect to a series, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, the premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange, and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company or another depositary named by us and identified in a prospectus supplement with respect to that series.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange or in the applicable indenture, we will make no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

Information Concerning the Debenture Trustee

The debenture trustee, other than during the occurrence and continuance of an event of default under the applicable indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the debenture trustee under such indenture must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the debenture trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, will we make interest payments by check which we will mail to the holder. Unless we otherwise indicate in a prospectus supplement, we will designate the corporate trust office of the debenture trustee in the City of New York as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the debenture trustee for the payment of the principal of or any premium or interest on any debt securities which remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Subordination of Subordinated Debt Securities

Our obligations pursuant to any subordinated debt securities will be unsecured and will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of senior indebtedness we may incur. It also does not limit us from issuing any other secured or unsecured debt.

DESCRIPTION OF WARRANTS

General

We may issue warrants to purchase shares of our common stock, preferred stock and/or debt securities in one or more series together with other securities or separately, as described in the applicable prospectus supplement. Below is a description of certain general terms and provisions of the warrants that we may offer. Particular terms of the warrants will be described in the warrant agreements and the prospectus supplement relating to the warrants.

The applicable prospectus supplement will contain, where applicable, the following terms of and other information relating to the warrants:

Transfer Agent and Registrar

The transfer agent and registrar for any warrants will be set forth in the applicable prospectus supplement.

DESCRIPTION OF RIGHTS

General

We may issue rights to our stockholders to purchase shares of our common stock, preferred stock or the other securities described in this prospectus. We may offer rights separately or together with one or more additional rights, debt securities, preferred stock, common stock, warrants or purchase contracts, or any combination of those securities in the form of units, as described in the applicable prospectus supplement. Each series of rights will be issued under a separate rights agreement to be entered into between us and a bank or trust company, as rights agent. The rights agent will act solely as our agent in connection with the certificates relating to the rights of the series of certificates and will not assume any obligation or relationship of agency or trust for or with any holders of rights certificates or beneficial owners of rights. The following description sets forth certain general terms and provisions of the rights to which any prospectus supplement may relate. The particular terms of the rights to which any prospectus supplement may relate and the extent, if any, to which the general provisions may apply to the rights so offered will be described in the applicable prospectus supplement. To the extent that any particular terms of the rights, rights agreement or rights certificates described in a prospectus supplement differ from any of the terms described below, then the terms described below will be deemed to have been superseded by that prospectus supplement. We encourage you to read the applicable rights agreement and rights certificate for additional information before you decide whether to purchase any of our rights.

We will provide in a prospectus supplement the following terms of the rights being issued:

Each right will entitle the holder of rights to purchase for cash the principal amount of shares of common stock, preferred stock or other securities at the exercise price provided in the applicable prospectus supplement. Rights may be exercised at any time up to the close of business on the expiration date for the rights provided in the applicable prospectus supplement.

Holders may exercise rights as described in the applicable prospectus supplement. Upon receipt of payment and the rights certificate properly completed and duly executed at the corporate trust office of the rights agent or any other office indicated in the prospectus supplement, we will, as soon as practicable, forward the shares of common stock, preferred stock or other securities, as applicable, purchasable upon exercise of the rights. If less than all of the rights issued in any rights offering are exercised, we may offer any unsubscribed securities directly to persons other than stockholders, to or through agents, underwriters or dealers or through a combination of such methods, including pursuant to standby arrangements, as described in the applicable prospectus supplement.

Rights Agent

The rights agent for any rights we offer will be set forth in the applicable prospectus supplement.

DESCRIPTION OF PURCHASE CONTRACTS

We may issue purchase contracts, including contracts obligating holders to purchase from us, and for us to sell to holders, a specific or variable number of our debt securities, shares of common stock, preferred stock, warrants or rights, or securities of an entity unaffiliated with us, or any combination of the above, at a future date or dates. Alternatively, the purchase contracts may obligate us to purchase from holders, and obligate holders to sell to us, a specific or variable number of our debt securities, shares of common stock, preferred stock, warrants, rights or other property, or any combination of the above. The price of the securities or other property subject to the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula described in the purchase contracts. We may issue purchase contracts separately or as a part of units each consisting of a purchase contract and one or more of our other securities described in this prospectus or securities of third parties, including U.S. Treasury securities, securing the holder’s obligations under the purchase contract. The purchase contracts may require us to make periodic payments to holders or vice versa and the payments may be unsecured or pre-funded on some basis. The purchase contracts may require holders to secure the holder’s obligations in a manner specified in the applicable prospectus supplement.

The applicable prospectus supplement will describe the terms of any purchase contracts in respect of which this prospectus is being delivered, including, to the extent applicable, the following:

The preceding description sets forth certain general terms and provisions of the purchase contracts to which any prospectus supplement may relate. The particular terms of the purchase contracts to which any prospectus supplement may relate and the extent, if any, to which the general provisions may apply to the purchase contracts so offered will be described in the applicable prospectus supplement. To the extent that any particular terms of the purchase contracts described in a prospectus supplement differ from any of the terms described above, then the terms described above will be deemed to have been superseded by that prospectus supplement. We encourage you to read the applicable purchase contract for additional information before you decide whether to purchase any of our purchase contracts.

DESCRIPTION OF UNITS

The following description, together with the additional information that we include in any applicable prospectus supplements summarizes the material terms and provisions of the units that we may offer under this prospectus. While the terms we have summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. The terms of any units offered under a prospectus supplement may differ from the terms described below.

We will incorporate by reference from reports that we file with the SEC, the form of unit agreement that describes the terms of the series of units we are offering, and any supplemental agreements, before the issuance of the related series of units. The following summaries of material terms and provisions of the units are subject to, and qualified in their entirety by reference to, all the provisions of the unit agreement and any supplemental agreements applicable to a particular series of units. We urge you to read the applicable prospectus supplements related to the particular series of units that we may offer under this prospectus, as well as any related free writing prospectuses and the complete unit agreement and any supplemental agreements that contain the terms of the units.

General

We may issue units consisting of common stock, preferred stock, one or more debt securities, warrants, rights or purchase contacts for the purchase of common stock, preferred stock and/or debt securities in one or more series, in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each security included in the unit. The unit agreement under which a unit is issued 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.

We will describe in the applicable prospectus supplement the terms of the series of units being offered, including:

The provisions described in this section, as well as those set forth in any prospectus supplement or as described under “Description of Common Stock,” “Description of Preferred Stock,” “Description of Debt Securities,” “Description of Warrants,” “Description of Rights” and “Description of Purchase Contracts” will apply to each unit, as applicable, and to any common stock, preferred stock, debt security, warrant, right or purchase contract included in each unit, as applicable.

Unit Agent

The name and address of the unit agent for any units we offer will be set forth in the applicable prospectus supplement.

Issuance in Series

We may issue units in such amounts and in such numerous distinct series as we determine.

Enforceability of Rights by Holders of Units

Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

CERTAIN PROVISIONS OF DELAWARE LAW AND OF THE COMPANY’S CERTIFICATE OF

INCORPORATION AND BYLAWS

Anti-Takeover Provisions of our Certificate of Incorporation and Bylaws

In addition to the board of directors’ ability to issue shares of preferred stock, our restated certificate of incorporation and amended and restated bylaws, contain other provisions thatcopies of which are intendedfiled as exhibits to enhance the likelihood of continuity and stability in the composition of the board of directors and which may have the effect of delaying, deferring or preventing a future takeover or change in control of our company unless such takeover or change in control is approved by our board of directors.

These provisions, summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging these proposals because negotiation of these proposals could result in an improvement of their terms.

Advance notice provisions for stockholder proposals. Our amended and restated bylaws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of our stockholders, including proposed nominations of persons for election to our board of directors, as well as procedures for including proposed nominations at special meetings at which directors are to be elected. Stockholders at our annual meeting may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board or by a stockholder who was a stockholder of record on the record date for the meeting, who is entitled to vote at the meeting and who has given to our secretary timely written notice, in proper form, of the stockholder’s intention to bring that business before the meeting, and who has complied with the procedures and requirements set forth in the bylaws. Although our bylaws do not give our board of directors the power to approve or disapprove stockholder nominations of candidates or proposals regarding other business to be conducted at a special or annual meeting, our bylaws may have the effect of precluding the conduct of some business at a meeting if the proper procedures are not followed or may discourage or defer a potential acquirer from conducting a solicitation of proxies to elect its own slate of directors or otherwise attempting to obtain control of us.

Special meetings of stockholders. Special meetings of the stockholders may be called only by our board of directors pursuant to a resolution adopted by a majority of our directors.

No stockholder action by written consent. Our amended and restated bylaws do not permit our stockholders to act by written consent. As a result, any action to be effected by our stockholders must be effected at a duly called annual or special meeting of the stockholders.

Super-majority stockholder vote required for certain actions. Our amended and restated bylaws require the affirmative vote of the holders of at least 66 2/3% of our outstanding voting stock in order to amend the bylaws. Our amended and restated bylaws may also be amended or repealed by a vote of a majority of our directors.

Provisions of Delaware Law Governing Business Combinations

We are subject to the “business combination” provisions of Section 203 of the General Corporation Law of Delaware (the “DGCL”). In general, such provisions prohibit a publicly held Delaware corporation from engaging in any “business combination” transactions with any “interested stockholder” for a period of three years after the date on which the person became an “interested stockholder,” unless:

A “business combination” is defined to include mergers, asset sales and other transactions resulting in financial benefit to a stockholder. In general, an “interested stockholder” is a person who, together with affiliates and associates, owns 15% or more of a corporation’s voting stock or within three years did own 15% or more of a corporation’s voting stock. The statute could prohibit or delay mergers or other takeover or change in control attempts with respect to us and, accordingly, may discourage attempts to acquire us.

Limitations on Liability and Indemnification of Officers and Directors

Our restated certificate of incorporation limits the liability of our officers and directors to the fullest extent permitted by the DGCL except for liability (i) for any breach of the director’s duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit, and our amended and restated bylaws provide that we will indemnify our officers and directors to the fullest extent permitted by such law. We have also entered into indemnification agreements with our officers and directors and expect to enter into a similar agreement with any new officers and directors.

LEGAL MATTERS

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts, will pass upon the validity of the issuance of the securities to be offered by this prospectus.

EXPERTS

Ernst & Young LLP, independent registered public accounting firm, has audited our financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2014, as set forth in their report,2020, filed with the SEC on April 15, 2021, which is incorporated by reference herein.

General

We are authorized to issue 765,000,000 shares of capital stock, $0.01 par value, consisting of 750.0 million shares of Common Stock, $0.01 par value per share, and 15.0 million shares of preferred stock, $0.01 par value per share.

Common Stock

As of August 10, 2021, there were 371,354,911 shares of Common Stock issued and outstanding. Each share of Common Stock shall have one (1) vote per share for all purposes. Our Common Stock does not provide preemptive, subscription or conversion rights and there is no redemption or sinking fund provisions or rights. Our Common Stockholders are not entitled to cumulative voting for election of Board members. Each share of our Common Stock entitles its holder to one vote in the election of each director and on all other matters voted on generally by our stockholders. Holders of our Common Stock will be entitled to dividends in such amounts and at such times as our Board of Directors in its discretion may declare out of funds legally available for the payment of dividends. We currently intend to retain our entire available discretionary cash flow to finance the growth, development and expansion of our business and do not anticipate paying any cash dividends on the Common Stock in the foreseeable future. Any future dividends will be paid at the discretion of our Board of Directors. As of August 10, 2021 approximately 87 stockholders of record of our Common Stock.

Preferred Stock

We are authorized to issue 15,000,000 preferred shares, of which we had 0 issued and outstanding as of August 10, 2021 and 278,188 shares were issued and outstanding as of December 31, 2020. All the preferred shares outstanding as of December 31, 2020 were converted in March 2021.

Options and Warrants

As of August 10, 2021 and December 31, 2020, we had approximately 52,181,562 and 22,644,000, respectively, shares of Common Stock underlying currently outstanding warrants and options.

Convertible Debt

As of August 10, 2021 and December 31, 2021, we had approximately 35,389,000 and 31,348,000, respectively, shares of Common Stock underlying convertible debt.

Dividend Rights

There are no restrictions in our Articles of Incorporation or Bylaws that prevent us from declaring dividends. The Delaware General Corporation Law, however, does prohibit us from declaring dividends where, after giving effect to the distribution of the dividend:

We have never declared or paid any cash dividends on our Common Stock. We currently intend to retain future earnings, if any, to finance the expansion of our business. As a result, we do not anticipate paying any cash dividends on our Common Stock in the foreseeable future.

Sales Pursuant to Rule 144

Any shares of Common Stock covered by this prospectus which qualify for sale pursuant to Rule 144 under the Securities Act may be sold under Rule 144 rather than pursuant to this prospectus.

Rule 144

In general, under Rule 144 as currently in effect, once we have been subject to public company reporting requirements for 90 days, a person (or persons whose shares are aggregated) who is not deemed to have been an affiliate of ours at any time during the three months preceding a sale, and who has beneficially owned restricted securities within the meaning of Rule 144 for a least six months (including any period of consecutive ownership of preceding non-affiliated holders) would be entitled to sell those shares, subject only to the availability of current public information about us. A non-affiliated person who has beneficially owned restricted securities within the meaning of Rule 144 for at least one year would be entitled to sell those shares without regard to the provisions of Rule 144.

In general, under Rule 144 as currently in effect, once we have been subject to public company reporting requirements for 90 days, our affiliates or persons selling shares on behalf of our affiliates who own shares that were acquired from us or an affiliate of ours at least six months prior to the proposed sale are entitled to sell upon expiration of the lock-up agreements described above, within any three-month period beginning 90 days after the date of this prospectus, a number of shares that does not exceed the greater of:

Sales under Rule 144 by our affiliates or persons selling shares on behalf of our affiliates are also subject to certain manner of sale provisions and notice requirements and to the availability of current public information about us.

Transfer Agent and Registrar

Our transfer agent is American Stock Transfer & Trust Company, a SEC Registered transfer agent. American Stock Transfer & Trust Company is located at 6201 15th Avenue, Brooklyn, NY 11219 and its telephone number is (800) 937-5449.

LEGAL MATTERS

The validity of the securities offered hereby will be passed upon for us by Disclosure Law Group, a Professional Corporation, San Diego, California (DLG).

EXPERTS

The consolidated financial statements of Oncotelic Therapeutics, Inc. (Formerly Mateon Therapeutics, Inc.) as of December 31, 2020 and 2019 and for each of the years in the two-year period ended December 31, 2020 incorporated in this prospectus and elsewhere in the registration statement. Our financial statements are incorporatedProspectus by reference from the Oncotelic Therapeutics, Inc. (Formerly Mateon Therapeutics, Inc.) Annual Report on Form 10-K for the year ended December 31, 2020 have been audited by Baker Tilly US, LLP, an independent registered public accounting firm, as stated in their reports thereon which report expresses an unqualified opinion and includes an explanatory paragraph relating to the Company’s ability to continue as a going concern, incorporated herein by reference, and have been incorporated in this Prospectus and Registration Statement in reliance on Ernst  & Young LLP’s report, given on theirupon such reports and upon the authority of such firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We are subject to the reportinginformational requirements of the Securities Exchange Act of 1934, as amended, and in accordance therewith we file annual, quarterly, and currentother reports, proxy statements and other information with the SEC. You may read and copy theseCommission under the Exchange Act. Such reports, proxy statements and other information, atincluding the SEC’s public reference facilities at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. You can request copies of these documents by writingRegistration Statement, and exhibits and schedules thereto, are available to the SEC and paying a fee forpublic through the copying cost. Please call the SECCommission’s website at 1-800-SEC-0330 for more information about the operation of the public reference facilities. SEC filings are also available at the SEC’s web site at http://www.sec.gov. Our common stock is listed on The Nasdaq Capital Market, and you can read and inspect our filings at the offices of the Financial Industry Regulatory Authority at 1735 K Street, Washington, D.C. 20006.

This prospectus is only part of a registration statement on Form S-3 that we

We have filed with the SECCommission a registration statement under the Securities Act of 1933, as amended, and therefore omits certain information contained in the registration statement. We have also filed exhibits and schedules with the registration statement that are excluded from this prospectus, and you should referrelating to the applicable exhibit or schedule for a complete descriptionoffering of any statement referring to any contract or other document. You may inspect a copy of thethese securities. The registration statement, including the attached exhibits, and schedules, without charge, at the public reference room or obtain a copy from the SEC upon payment of the fees prescribed by the SEC.

We also maintain a website at www.oxigene.com, through which you can access our SEC filings. The information set forth on our website is not part of this prospectus.

INCORPORATION OF DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with them. Incorporation by reference allows us to disclose important information to you by referring you to those other documents. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. We filed a registration statement on Form S-3 under the Securities Act of 1933, as amended, with the SEC with respect to the securities we may offer pursuant to this prospectus. This prospectus omits certain information contained in the registration statement, as permitted by the SEC. You should refer to the registration statement, including the exhibits, for furthercontains additional relevant information about us and the securities we may offer pursuant to this prospectus. Statementssecurities. This prospectus does not contain all of the information set forth in this prospectus regarding the provisions of certainregistration statement.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The following documents filed by us with orthe SEC are incorporated by reference in the registration statement are not necessarily complete and each statement is qualified in all respects by that reference. Copies of all or any part of the registration statement, including the documents incorporated by reference or the exhibits, may be obtained upon payment of the prescribed rates at the offices of the SEC listed above in “Where You Can Find More Information.” The documents we are incorporating by reference are:this prospectus:

Unless otherwise noted, the SEC file number for each of the documents listed above is 000-21990.prospectus.

In addition, all reports and other documents filed by us pursuant to the Exchange Act after the date of the initial registration statement and prior to effectiveness of the registration statement shall be deemed to be incorporated by reference into this prospectus.

Any statement contained in this prospectus or in a document incorporated or deemed to be incorporated by reference into this prospectus willherein shall be deemed to be modified or superseded for the purposes of this prospectusregistration statement to the extent that a statement contained herein or in this prospectus or any other subsequently filed document thatwhich also is or deemed to be incorporated by reference into this prospectusherein modifies or supersedes thesuch statement. Any statement so modified or superseded willshall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.registration statement.

You may request, orally or in writing,

We will provide to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any or all of the documentsinformation that has been incorporated herein by reference. These documents will be providedreference in the prospectus but not delivered with the prospectus. You may request a copy of these filings, excluding the exhibits to yousuch filings which we have not specifically incorporated by reference in such filings, at no cost, by contacting: Investor Relations, OXiGENE,writing to or calling us at:

Oncotelic Therapeutics, Inc., 701 Gateway Boulevard,

29397 Agoura Road, Suite 210, South San Francisco, California 94080, 107

Agoura Hills, CA 91301

(650) 635-7000.635-7000

This prospectus is part of a registration statement we filed with the SEC. You should only rely only on the information or representations contained in or incorporated by reference into, this prospectus and any accompanying prospectus supplement. We have not authorized anyone to provide you with information different fromother than that contained in this prospectus or incorporated by referenceprovided in this prospectus. We are not making offers to sellan offer of the securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or any accompanying prospectus supplement is accurate as of any date other than the date on the front of the document.

70,618,065 Shares

Common Stock

PROSPECTUS

We have not authorized any dealer, salesperson or other person to give any information or to make any representations not contained in this prospectus. You must not rely on any unauthorized information. This prospectus is not an offer to sell these securities in any jurisdiction in which suchwhere an offer or solicitationsale is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make such offer or solicitation.

August 20, 2021

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

The following table sets forth an itemization

Item 14. Other Expenses of Issuance and Distribution.

All amounts below are estimates other than the Commission’s registration fee. We are paying all expenses of the variousOffering listed above. No portion of these expenses all of which wewill be borne by the Selling Shareholders. The Selling Shareholders, however, will pay any other expenses incurred in connection with the issuance and distributionselling their Common Stock, including any brokerage commissions or costs of the securities being registered. All of the amounts shown are estimated except the SEC Registration Fee.sale.

Subsection (a) of Directors and Officers.

Section 145 of the DGCL empowersDelaware General Corporation Law permits a corporation to indemnify any person who wasdirector or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that he is or was a director, employee or agentofficer of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’attorney’s fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with suchany action, suit or proceeding brought by reason of the fact that such person is or was a director or officer of the corporation, if hesuch person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, and, with respect to any criminal action or proceeding, if he or she had no reasonable causereason to believe his or her conduct was unlawful.

Subsection (b) of Section 145 In a derivative action, one brought by or on behalf of the DGCL empowers a corporation to indemnify any person who was or is a party or is threatened tocorporation), indemnification may be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that such person acted in any of the capacities set forth above, againstprovided only for expenses (including attorneys’ fees) actually and reasonably incurred by himany director or officer in connection with the defense or settlement of such an action or suit if hesuch person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, and except that no indemnification mayshall be made with respect to any claim, issue or matter as to whichprovided if such person shall have been adjudged to be liable to the corporation, unless and only to the extent that the Court of Chancery or the court in which suchthe action or suit was brought shall determine upon application that despite the adjudication of liability but in view of all of the circumstances of the case, such persondefendant is fairly and reasonably entitled to indemnity for such expenses whichdespite such adjudication of liability.

Our Articles of Incorporation contain a provision that no director or officer will be personally liable to us or our stockholders for damages regarding breaches of fiduciary duty. This limitation on liability may reduce the Courtlikelihood of Chanceryderivative litigation against our officers and directors and may discourage or such other court shall deem proper.deter our stockholders from suing our officers and directors based upon breaches of their duties to our Company.

Section 145

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the DGCL further provides thatCompany pursuant to the extentforegoing provisions, or otherwise, the Company has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Company of expenses incurred or paid by a director, officer employee or agentcontrolling person of a corporation has been successful on the merits or otherwiseCompany in the successful defense of any action, suit or proceeding referred to in subsections (a) and (b) or in the defense of any claim, issue or matter therein, he shall be indemnified against expenses (including attorneys’ fees) actually and reasonably incurredproceeding) is asserted by him in connection therewith; that indemnification or advancement of expenses provided for by Section 145 shall not be deemed exclusive of any other rights to which the indemnified party may be entitled; and empowers the corporation to purchase and maintain insurance on behalf of asuch director, officer employee or agent of the corporation against any liability asserted against him or incurred by him in any such capacity or arising out of his status as such whether or not the corporation would have the power to indemnify him against such liabilities under Section 145.

II-1

Reference is also made to Section 102(b)(7) of the DGCL, which enables a corporation in its certificate of incorporation to eliminate or limit the personal liability of a director for monetary damages for violations of a director’s fiduciary duty, except for liability (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL (providing for liability of directors for unlawful payment of dividends or unlawful stock purchases or redemptions) or (iv) for any transaction from which the director derived an improper personal benefit.

Article Ninth of our restated certificate of incorporation, as amended, provides that, to the fullest extent permitted by the DGCL, a director shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit.

Article IX, Section 3 of our amended and restated by-laws provides that we shall, to the fullest extent permitted by the DGCL, indemnify our directors and may, if authorized by our board of directors, indemnify our officers, employees and agents and any and all persons whom we shall have power to indemnify against any and all expenses, liabilities or other matters.

We have entered into an indemnification agreement with each of our directors, in order to provide consistent indemnification arrangements for all directors. The indemnification agreement provides that each director who was or is made a party or is threatened to be made a party to any action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he is or was one of the Company’s directors, shall be indemnified by the Company to the fullest extent authorized by the DGCL against all expense, liability and loss (including attorneys’ fees, judgments, fines or penalties and amounts paid in settlement) reasonably incurredcontrolling person in connection with the securities being registered, the Company will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such legal proceedings. A directorindemnification by it is against public policy as expressed in the Securities Act of 1933 and will not receive indemnification under this agreement if he is found not to have acted in good faith and in a manner he reasonably believed to be in, or not opposed to,governed by the Company’s best interests.final adjudication of such issue.

Item 16. Exhibits.