Filed Pursuant to Rule 424(b)(5)

Registration No. 333-251005

Prospectus Supplement

(to Prospectus dated December 17, 2020)

1,700,000 Shares of Common Stock

         We are offering 1,700,000 shares of our common stock, par value $0.0001 per share (“Common Stock”) to certain investors pursuant to this prospectus supplement and the accompanying prospectus. Such investors will also receive Series A common warrants to purchase up to 1,700,000 shares of our Common Stock (the “Series A Common Warrants”) and Series B common warrants to purchase up to 1,700,000 shares of our Common Stock (the “Series B Common Warrants”, together with the Series A Common Warrants the “Common Warrants”) in a concurrent private placement. The Common Warrants and the shares issuable upon exercise thereof are not being registered under the Securities Act of 1933, as amended (the “Securities Act”), and are not offered pursuant to this prospectus supplement and the accompanying prospectus. The Common Warrants are being offered pursuant to an exemption from the registration requirements of the Securities Act provided in Section 4(a)(2) of the Securities Act and/or Regulation D promulgated thereunder. The offering price for each share of Common Stock and accompanying Common Warrants to purchase one share of Common Stock is $3.60. The Common Warrants have an exercise price of $3.35 per warrant. The Series A Common Warrants are exercisable immediately upon issuance, and will expire five (5) years from the date of issuance. The Series B Common Warrants are exercisable immediately upon issuance, and will expire eighteen (18) months from the date of issuance.

The shares of Common Stock and the accompanying Common Warrants, can only be purchased together in this offering but will be issued separately and will be immediately separable upon issuance. There is no established public trading market for the Common Warrants, and we do not expect a market to develop. We do not intend to apply for listing of the Common Warrants on any securities exchange or nationally recognized trading system. Without an active trading market, the liquidity of the Common Warrants will be limited.

Effective as of December 6, 2022, we filed a certificate of amendment of our restated certificate of incorporation to effect a reverse stock split of the issued and outstanding shares of our Common Stock, at a ratio of 1 share for 10 shares (the “Reverse Stock Split”). Unless otherwise indicated, all share numbers herein, including Common Stock and all securities convertible into Common Stock, give effect to the Reverse Stock Split. However, documents incorporated by reference into this prospectus that were filed prior to December 6, 2022, do not give effect to the Reverse Stock Split.

Our Common Stock is listed on the Nasdaq Capital Market under the symbol “CKPT.” On March 30, 2023, the closing price of our Common Stock as reported on the Nasdaq Capital Market was $3.35 per share.

We have engaged H.C. Wainwright & Co., LLC to act as our exclusive placement agent in connection with this offering. The placement agent has agreed to use its reasonable best efforts to arrange for the sale of the securities offered in this offering. The placement agent is not purchasing or selling any of the securities we are offering, and the placement agent is not required to arrange the purchase or sale of any specific number of securities or dollar amount. There is no required minimum number of securities that must be sold as a condition to completion of this offering, and there are no arrangements to place the funds in an escrow, trust, or similar account. We will also issue to the placement agent, or its designees, warrants to purchase up to 102,000 shares of Common Stock (the “Placement Agent Warrants”) as part of the compensation payable to the placement agent. The Placement Agent Warrants will have substantially the same terms as the Series A Common Warrants described above, except that the Placement Agent Warrants will have an exercise price of $4.50 per share (representing 125% of the combined purchase price per Share and accompanying Common Warrants) and will expire five years following the commencement of the sales pursuant to this offering. See “Plan of Distribution” beginning on page S-15 of this prospectus supplement for more information regarding these arrangements.

Investing in our securities involves a high degree of risk. See the information contained under “Risk Factors” on page S-8 of this prospectus supplement and in the documents incorporated herein by reference.

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

Delivery of the shares of Common Stock and Common Warrants is expected to be made on or about April 4, 2023, subject to satisfaction of customary closing conditions.

H.C. Wainwright & Co.

The date of this prospectus supplement is March 30, 2023

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying prospectus are part of a “shelf” registration statement on Form S-3 (File No. 333-251005) that we originally filed with the U.S. Securities and Exchange Commission (the “SEC”), on November 27, 2020 and which became effective on December 17, 2020.

This document is in two parts. The first part is this prospectus supplement which describes the specific terms of an offering of shares of our Common Stock, and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus, provides more general information, some of which may not apply to this offering. Generally, when we refer to this prospectus supplement, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the accompanying prospectus or any document incorporated by reference that we filed with the SEC before the date of this prospectus supplement, you should rely on the information in this prospectus supplement, provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date, for example, a document incorporated by reference in the accompanying prospectus – the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties, and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty, or covenant to you. Moreover, such representations, warranties, or covenants were accurate only as of the date when made. Accordingly, such representation, warranties, and covenants should not be relied upon as accurately representing the current state of our affairs.

We have not and the placement agent has not authorized anyone to provide you with any information or to make any representations other than those included or incorporated by reference in this prospectus supplement and the accompanying prospectus and any relevant free writing prospectus. If you receive any information not authorized by us, we and the placement agent take no responsibility for, and can provide no assurance as to the reliability of, such information. We are not making an offer to sell the securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus or any relevant free writing prospectus is accurate as of any date other than its respective date.

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

Unless the context otherwise requires, “Checkpoint,” the “Company,” “we,” “us,” “our” and similar names refer to Checkpoint Therapeutics, Inc.

FORWARD-LOOKING STATEMENTS

Certain matters discussed in this prospectus supplement may constitute forward-looking statements for purposes of the Securities Act of 1933, as amended, or the Securities Act, and the Securities Exchange Act of 1934, as amended, or the Exchange Act, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from the future results, performance or achievements expressed or implied by such forward-looking statements. The words “anticipate,” “believe,” “estimate,” “may,” “expect,” “will,” “could,” “project,” “intend” and similar expressions are generally intended to identify forward-looking statements. Our actual results may differ materially from the results anticipated in these forward-looking statements due to a variety of factors, including, without limitation, those discussed under the caption “Risk Factors” contained in this prospectus supplement, the accompanying prospectus, any applicable free writing prospectus, or under similar heading in the other documents that are incorporated by reference into this prospectus supplement. All written or oral forward-looking statements attributable to us are expressly qualified in their entirety by these cautionary statements. Such forward-looking statements include, but are not limited to, statements about our:

The forward-looking statements contained in this prospectus supplement reflect our views and assumptions only as of the date of this prospectus supplement, respectively. Except as required by law, we assume no responsibility for updating any forward-looking statements. We qualify all of our forward-looking statements by these cautionary statements. New risks and uncertainties arise from time to time, and it is impossible for us to predict these events or how they may affect us. In addition, with respect to all of our forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995.

PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights information contained elsewhere or incorporated by reference in this prospectus supplement and the accompanying prospectus and in the documents we incorporate by reference. This summary does not contain all of the information that you should consider before deciding to invest in our common stock. You should read this entire prospectus supplement and the accompanying prospectus carefully, including the ‘‘Risk Factors’’ sections contained in this prospectus supplement and the documents incorporated by reference herein, our consolidated financial statements and the related notes and the other documents incorporated by reference herein.

Our Business

We are a clinical-stage immunotherapy and targeted oncology company focused on the acquisition, development and commercialization of novel treatments for patients with solid tumor cancers. We are evaluating our lead antibody product candidate, cosibelimab, an anti-programmed death-ligand 1 antibody licensed from the Dana-Farber Cancer Institute, in an ongoing global, open-label, multicohort Phase 1 clinical trial in checkpoint therapy-naïve patients with selected recurrent or metastatic cancers, including ongoing cohorts in locally advanced and metastatic cutaneous squamous cell carcinoma (“CSCC”) intended to support one or more applications for marketing approval. Based on top-line and interim results in metastatic and locally advanced CSCC, respectively, we submitted a Biologics License Application to the U.S. Food and Drug Administration (“FDA”) for these indications in January 2023, which application is filed and under review with a Prescription Drug User Fee Act goal date of January 3, 2024. In addition, we are evaluating our lead small-molecule, targeted anti-cancer agent, olafertinib, a third-generation epidermal growth factor receptor (“EGFR”) inhibitor, as a potential new treatment for patients with EGFR mutation-positive non-small cell lung cancer (“NSCLC”). 

In June 2022, we announced interim results from a registration-enabling cohort of our multi-regional, Phase 1 clinical trial of cosibelimab in patients with locally advanced CSCC that are not candidates for curative surgery or radiation. Cosibelimab demonstrated a confirmed objective response rate (“ORR”) of 54.8% (95% CI: 36.0, 72.7) based on independent central review of 31 patients enrolled in the cohort using Response Evaluation Criteria in Solid Tumors version 1.1 (“RECIST 1.1”).

In January 2022, we announced top-line results from a registration-enabling cohort of our multi-regional, Phase 1 clinical trial of cosibelimab in patients with metastatic CSCC. The cohort met its primary endpoint, with cosibelimab demonstrating a confirmed ORR of 47.4% (95% CI: 36.0, 59.1) based on independent central review of 78 patients enrolled in the metastatic CSCC cohort using RECIST 1.1.

We have also entered into various collaboration agreements with TG Therapeutics, Inc., a related party, to develop and commercialize certain assets in connection with our licenses in the field of hematological malignancies, while we retain the right to develop and commercialize these assets in solid tumors.

To date, we have not received approval for the sale of any product candidate in any market and, therefore, have not generated any product sales from any product candidates. In addition, we have incurred substantial operating losses since our inception, and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2022, we have an accumulated deficit of $262.5 million.

We are a majority-controlled subsidiary of Fortress Biotech, Inc (“Fortress”). 

Corporate Information

Checkpoint Therapeutics, Inc. was incorporated in Delaware on November 10, 2014, and commenced principal operations in March 2015. Our principal executive offices are located at 95 Sawyer Road, Suite 110, Waltham, MA 02453, and our telephone number is (781) 652-4500. We maintain a website on the Internet at www.checkpointtx.com and our e-mail address is ir@checkpointtx.com. Our internet website, and the information contained on it, are not to be considered part of this prospectus supplement or the accompanying prospectus. For further information regarding us and our financial information, you should refer to our recent filings with the SEC. See “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

A certificate of amendment of Checkpoint’s certificate of incorporation for a 1-for-10 reverse split of Checkpoint’s issued and outstanding Common Stock was effective as of December 6, 2022. Unless otherwise indicated, all share numbers herein, including Common Stock and all securities convertible into Common Stock, give effect to the Reverse Stock Split. However, documents incorporated by reference into this prospectus that were filed prior to December 6, 2022, do not give effect to the Reverse Stock Split.

Our Common Stock is listed on the Nasdaq Capital Market under the symbol “CKPT”.

THE OFFERING

Unless otherwise indicated, all information in this prospectus related to the number of shares of our Common Stock to be outstanding immediately after this offering is based on 10,286,683 shares of our common stock and Class A common stock outstanding as of December 31, 2022. The number of shares outstanding as of December 31, 2022 excludes:

Further, the number of shares of common stock to be outstanding after this offering does not take into account 35,714 shares issued to Fortress on February 22, 2023 related to the February 2023 registered direct offering and 368,907 shares issued to Fortress on January 1, 2023 pursuant to the annual equity fee under the terms of the Founder’s Agreement between the Company and Fortress.

Unless otherwise indicated, all information in this prospectus supplement assumes (i) no exercise of outstanding stock options or warrants or achievement of performance-based restricted stock units after December 31, 2022 and (ii) no exercise of the Common Warrants, or Placement Agent Warrants offered and sold in this offering and the concurrent private placement.

RISK FACTORS

Investment in our securities involves risks. Before deciding whether to invest in our securities, you should consider carefully the risk factors discussed below and those contained in the section entitled “Risk Factors” contained in our Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the SEC on March 31, 2023, which is incorporated herein by reference in its entirety, as well as any amendment or update to our risk factors reflected in subsequent filings with the SEC. If any of the risks or uncertainties described in our SEC filings actually occurs, our business, financial condition, results of operations or cash flow could be materially and adversely affected. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. The risks and uncertainties we have described are not the only ones facing our company. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations.

Risks Related to this Offering

You will experience immediate and substantial dilution.

Because the offering price per share in this offering exceeds the net tangible book value per share of our Common Stock outstanding prior to this offering you will incur an immediate and substantial dilution in the net tangible book value of the shares of Common Stock you purchase in this offering. After giving effect to the sale by us of: (i) 1,700,000 shares of our Common Stock at a price of $3.60 per share of Common Stock and associated Common Warrants, and after deducting placement agent fees and estimated offering expenses payable by us and assuming no exercise of the Common Warrants, you will experience immediate dilution of $4.77 per share, representing the difference between the effective offering price per share and our as adjusted net tangible book value per share as of December 31, 2022. The exercise of warrants, including the Common Warrants issued in the concurrent private placement, exercise of outstanding stock options, and vesting of other stock awards may result in further dilution of your investment. See the section entitled “Dilution” appearing elsewhere in this prospectus supplement for a more detailed illustration of the dilution you would incur if you participate in this offering.

The trading price of our Common Stock could be highly volatile, which could result in substantial losses for purchasers of our Common Stock in this offering.

Our stock price is volatile. The stock market in general and the market for pharmaceutical and biotechnology companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. As a result of this volatility, you may not be able to sell your Common Stock at or above the offering price and you may lose some or all of your investment. The market price for our Common Stock may be influenced by many factors, including:

In the past, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for pharmaceutical and biotechnology companies, which have experienced significant stock price volatility in recent years.

We have broad discretion in the use of the net proceeds of this offering and may not use them effectively.

We intend to use the net proceeds from this offering for working capital and general corporate purposes, including the manufacturing of cosibelimab and certain pre-commercial activities in anticipation of potential approval and commercial launch. However, our management will have broad discretion in the application of the net proceeds from this offering and could spend the proceeds in ways that do not improve our results of operations or enhance the value of our common stock. The failure by management to apply these funds effectively could result in financial losses that could have a material adverse effect on our business, cause the price of our common stock to decline and delay the development of our product candidates.

You may experience future dilution as a result of future equity offerings.

In order to raise additional capital, we may in the future offer additional shares of our Common Stock or other securities convertible into or exchangeable for our Common Stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. If we sell Common Stock, convertible securities, or other equity securities, investors may be materially diluted by subsequent sales.

Risks Related to our Common Stock

There are risks associated with the Reverse Stock Split.

A certificate of amendment of Checkpoint’s certificate of incorporation for a 1-for-10 reverse split of Checkpoint’s issued and outstanding Common Stock was effective as of December 6, 2022. There are risks associated with the Reverse Stock Split and there is no assurance that:

USE OF PROCEEDS

We expect to receive net proceeds of approximately $5.5 million from this offering, after deducting estimated offering expenses payable by us, including the placement agent fees. We intend to use the net proceeds of this offering for working capital and general corporate purposes, including the manufacturing of cosibelimab and certain pre-commercial activities in anticipation of potential approval and commercial launch.

DILUTION

If you invest in our securities in this offering, your ownership interest will be diluted to the extent of the difference between the effective offering price per share of our Common Stock and Common Warrants in this offering and the as adjusted net tangible book value per share of our Common Stock immediately after this offering. The net tangible book value of our Common Stock as of December 31, 2022 was approximately $(19.5) million, or approximately $(1.89) per share of Common Stock based upon 10,286,683 shares of common stock and Class A common stock outstanding. Net tangible book value per share is equal to our total tangible assets, less our total liabilities, divided by the total number of shares of Common Stock outstanding as of December 31, 2022.

Net tangible book value dilution per share to investors participating in this offering represents the difference between the effective offering price per share paid by purchasers of securities in this offering and the as adjusted net tangible book value per share of our Common Stock immediately after this offering. After giving effect to the sale of 1,700,000 shares of our Common Stock and associated Common Warrants in this offering and the concurrent private placement at an offering price of $3.60 per share of Common Stock and accompanying Common Warrants, and after deducting estimated placement agent fees and offering expenses payable by us, and assuming no exercise of the Common Warrants, our as adjusted net tangible book value as of December 31, 2022 would have been approximately $(14.0) million, or $(1.17) per share. This represents an immediate increase in net tangible book value of $0.72 per share to existing stockholders and immediate dilution of $4.77 per share to investors purchasing our securities in this offering at the offering price. The following table illustrates this dilution on a per share basis:

The discussion and table above assume no exercise of Common Warrants sold in this offering and concurrent private placement and are based on 10,286,683 shares of common stock and Class A common stock outstanding as of December 31, 2022. The number of shares outstanding as of December 31, 2022 excludes:

Further, the number of shares of common stock to be outstanding after this offering does not take into account 35,714 shares issued to Fortress on February 22, 2023 related to the February 2023 registered direct offering and 368,907 shares issued to Fortress on January 1, 2023 pursuant to the annual equity fee under the terms of the Founder’s Agreement between the Company and Fortress.

To the extent that outstanding options or warrants as of December 31, 2022 have been or may be exercised, performance-based restricted stock units have been achieved, or other shares issued, investors purchasing our securities in this offering may experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

DIVIDEND POLICY

We have never declared or paid any dividends. We currently intend to retain earnings, if any, for use in our business. We do not anticipate paying dividends in the foreseeable future. Any future determination to declare dividends will be made at the discretion of our board of directors and will depend on our financial condition, operating results, capital requirements, general business conditions, and other factors that our board of directors may deem relevant.

Description of Securities We Are Offering

Description of Capital Stock

The following description summarizes the material terms of Checkpoint capital stock. Because it is only a summary, it does not contain all the information that may be important to you. For a complete description of our capital stock, you should refer to our certificate of incorporation, our bylaws and to the provisions of applicable Delaware law.

Common Stock

Our common stock is traded on The Nasdaq Capital Market, or the Exchange, under the symbol “CKPT.”

The authorized capital stock of Checkpoint consists of 50,000,000 shares of common stock, of which 700,000 shares have been designated as Class A common stock. The description of our Class A common stock in this item is for information purposes only. All of the Class A common stock has been issued to Fortress. Class A common stock is identical to common stock other than as to voting rights, the election of directors for a definite period, and conversion rights. On any matter presented to our stockholders for their action or consideration at any meeting of our stockholders (or by written consent of stockholders in lieu of meeting), each holder of outstanding shares of Class A common stock will be entitled to cast for each share of Class A common stock held by such holder as of the record date for determining stockholders entitled to vote on such matter, the number of votes that is equal to one and one-tenth (1.1) times a fraction, the numerator of which is the sum of the shares of outstanding common stock and the denominator of which is the number of shares of outstanding Class A common stock. Thus, the Class A common stock will at all times constitute a voting majority. For a period of ten (10) years from the date of the first issuance of shares of Class A common stock expiring in 2025 (the “Class A Director Period”), the holders of record of the shares of Class A common stock (or other capital stock or securities issued upon conversion of or in exchange for the Class A common stock), exclusively and as a separate class, will be entitled to appoint or elect the majority of the directors of Checkpoint (the “Class A Directors”). Finally, each share of Class A common stock is convertible, at the option of the holder, into one fully paid and nonassessable share of common stock (the “Conversion Ratio”), subject to certain adjustments.

If Checkpoint at any time effects a subdivision of the outstanding common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) by any stock split, stock dividend, recapitalization or otherwise, the applicable Conversion Ratio in effect immediately before that subdivision will be proportionately decreased so that the number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) issuable on conversion of each share of Class A common stock will be increased in proportion to such increase in the aggregate number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) outstanding. If Checkpoint at any time combines the outstanding shares of common stock, the applicable Conversion Ratio in effect immediately before the combination will be proportionately increased so that the number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) issuable on conversion of each share of Class A common stock will be decreased in proportion to such decrease in the aggregate number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) outstanding. Additionally, if any reorganization, recapitalization, reclassification, consolidation or merger involving Checkpoint occurs in which the common stock (but not the Class A common stock) is converted into or exchanged for securities, cash or other property (other than a transaction involving the subdivision or combination of the common stock), then, following any such reorganization, recapitalization, reclassification, consolidation or merger, each share of Class A common stock becomes convertible into the kind and amount of securities, cash or other property which such Class A Stockholder would have been entitled to receive had he or she converted the Class A Shares immediately before said transaction. In such case, appropriate adjustment (as determined in good faith by the Board of Directors of Checkpoint) will be made in the application of the provisions of Checkpoint’s Amended and Restated Certificate of Incorporation relating the subdivision or combination of the common stock with respect to the rights and interests thereafter of the holders of the Class A common stock, such that the provisions set forth in of Checkpoint’s Amended and Restated Certificate of Incorporation relating to the subdivision or combination of the common stock (including the provisions with respect to changes in and other adjustments of the applicable Conversion Ratio) will thereafter be applicable, as nearly as reasonably may be, in relation to any securities or other property thereafter deliverable upon the conversion of the Class A common stock. Checkpoint is not authorized to issue preferred stock.

Dividends

The holders of outstanding shares of our common stock, including Class A Common Stock, are entitled to receive dividends out of funds legally available at the times and in the amounts that our board of directors may determine. All dividends are non-cumulative.

Voting Rights

The holders of our common stock are entitled to one vote for each share of common stock held on all matters submitted to a vote of the stockholders, including the election of directors, except as to the Class A Directors during the Class A Director Period. Our certificate of incorporation and bylaws do not provide for cumulative voting rights.

Liquidation and Dissolution

Upon our liquidation, dissolution, or winding-up, the assets legally available for distribution to our stockholders would be distributable ratably among the holders of our common stock, including Class A Common Stock, outstanding at that time after payment of other claims of creditors, if any.

Other

The holders of our common stock have no preemptive, conversion, or subscription rights, and there are no redemption or sinking fund provisions applicable to our common stock.

All of the outstanding shares of our common stock, including Class A common stock, are duly issued, fully paid and non-assessable.

PRIVATE PLACEMENT

Concurrently with the sale of common stock in this offering, we will issue to the investors in this offering, Series A Common Warrants to purchase up to 1,700,000 shares of Common Stock at an exercise price of $3.35 per share, exercisable for a period of five years from the date of issuance, and Series B Common Warrants to purchase up to 1,700,000 shares of Common Stock at an exercise price of $3.35 per share, exercisable for a period of 18 months from the date of issuance. We will receive gross proceeds from the concurrent private placement transaction solely to the extent such warrants are exercised for cash.

The Common Warrants and the common stock issuable upon the exercise of such warrants are not being registered under the Securities Act, are not being offered pursuant to this prospectus supplement and the accompanying prospectus and are being offered pursuant to the exemption provided in Section 4(a)(2) under the Securities Act and Rule 506(b) promulgated thereunder. Accordingly, the investors may only sell common stock issued upon exercise of the Common Warrants pursuant to an effective registration statement under the Securities Act covering the resale of those shares, an exemption under Rule 144 under the Securities Act or another applicable exemption under the Securities Act.

The summary below is not complete and is subject to, and qualified in its entirety by, the provisions of the Common Warrants, which will be filed with the SEC as an exhibit to a Report on Form 8-K in connection with this offering and incorporated by reference into the registration statement of which this prospectus supplement and the accompanying prospectus form a part. Prospective investors should carefully review the terms and provisions of the form of the Common Warrants for a complete description of the terms and conditions of the Common Warrants.

Series A Warrants and Series B Warrants

Duration and Exercise Price

Each Series A Warrant and Series B Warrant offered hereby will be a warrant to purchase one share of Common Stock and will have an initial exercise price equal to $3.35 per share. The Series A Warrants will be immediately exercisable and will expire five years from the date of issuance. The Series B Warrants will be immediately exercisable and will expire eighteen months from the date of issuance. The exercise price and number of shares of Common Stock issuable upon exercise is subject to appropriate adjustment in the event of share dividends, share splits, reorganizations or similar events affecting our Common Stock and the exercise price. Subject to the rules and regulations of the applicable trading market, we may at any time during the term of the Common Warrants, subject to the prior written consent of the holders, reduce the then current exercise price to any amount and for any period of time deemed appropriate by our board of directors. The Common Warrants will be issued separately from the shares of Common Stock.

Placement Agent Warrants

We have also agreed to issue to issue to H.C. Wainwright & Co., LLC (or its permitted assignees) Placement Agent Warrants to purchase a number of shares of our Common Stock equal to 6.0% of the aggregate number of shares of Common Stock included in this offering, or 102,000 shares of Common Stock, at an exercise price equal to 125% of the offering price of the Common Stock and accompanying Common Warrants in this offering, or $4.50 per share, and to pay certain expenses of the placement agent in connection with this offering. The Placement Agent Warrants will be exercisable immediately and will expire five years from the commencement of sales in the offering. Except as provided herein, the Placement Agent Warrants will have substantially the same terms as the Series A Warrants issued to the investors in the offering. The summary of certain terms and provisions of the Placement Agent Warrants is not complete and is subject to, and qualified in its entirety by, the provisions of the form of which will be filed as an exhibit to our Current Report on Form 8-K and which will be incorporated by reference herein.

PLAN OF DISTRIBUTION

We have engaged H.C. Wainwright & Co., LLC (the “placement agent”) to act as our exclusive placement agent, on a reasonable best-efforts basis, in connection with this offering pursuant to this prospectus supplement and accompanying prospectus. The terms of this offering are subject to market conditions and negotiations between us, the placement agent, and prospective investors. The engagement agreement does not give rise to any commitment by the placement agent to purchase any of the securities, and the placement agent will have no authority to bind us by virtue of the engagement agreement. The placement agent is not purchasing the securities offered by us in this offering and is not required to sell any specific number or dollar amount of securities but will assist us in this offering on a reasonable best-efforts basis. Further, the placement agent does not guarantee that it will be able to raise new capital in any prospective offering. The placement agent may engage sub-agents or selected dealers to assist with the offering. The placement agent has no commitment to buy any of the securities offered pursuant to this prospectus supplement and accompanying prospectus. We have entered into a securities purchase agreement directly with the investors in connection with this offering, and we will only sell to investors who have entered into the securities purchase agreement. We may not sell the entire amount of shares of our Common Stock offered pursuant to this prospectus supplement.

We expect to deliver the shares of our Common Stock being offered pursuant to this prospectus supplement on or about April 4, 2023, subject to satisfaction of customary closing conditions.

We have agreed to indemnify the placement agent against specified liabilities relating to or arising out of the agent’s activities as placement agent.

Fees and Expenses

We have agreed to pay the placement agent in connection with this offering (i) a cash fee equal to 7.0% of the aggregate gross proceeds of this offering, (ii) a management fee equal to 1.0% of the aggregate gross proceeds of this offering, (iii)  a non-accountable expense allowance of $75,000, and (iv) $15,950 for the clearing expenses.

We estimate that the total expenses payable by us in connection with this offering, excluding the placement agent fees and expenses referred to above, will be approximately $50,000.

Placement Agent Warrants

In addition, we have agreed to issue to the placement agent, or its designees, at the closing of this offering, Placement Agent Warrants to purchase 6.0% of the number of shares of our Common Stock sold in this offering (or warrants to purchase up to 102,000 shares of our Common Stock), at an exercise price of $4.50 per share (representing 125% of the offering price per Share and accompanying Common Warrants).

The Placement Agent Warrants will be exercisable immediately upon issuance and will expire five years from the commencement of sales in the offering.

Except as provided above, The Placement Agent Warrants will have substantially the same terms as the Series A Warrants issued to the investors in the offering.

Tail Financing Payments

We have also agreed to pay the placement agent, subject to certain exceptions, a tail fee equal to the cash and warrant compensation in this offering, if any investor, who was contacted or introduced to us by placement agent during the term of the engagement, provides us with capital in any public or private offering or other financing or capital raising transaction during the 12-month period following the termination or expiration of our engagement agreement.

Right of First Refusal

In addition, we have granted a right of first refusal to the placement agent pursuant to which it has the right to act as the exclusive manager or underwriter or agent, as applicable, if we or our subsidiaries finance any indebtedness using an agent, or raise capital through a public or private offering of equity, equity-linked or debt securities at any time prior to the 10-month anniversary of the consummation date of this offering.

Lock-up Agreement

We have agreed to be subject to a lock-up for a period of 45 days following the date of closing of the offering pursuant to this prospectus supplement and accompanying prospectus. This means that, during the applicable lock-up period, we may not issue, enter into any agreement to issue or announce the issuance or proposed issuance of any shares of Common Stock or their equivalents, subject to certain exceptions. In addition, subject to certain exceptions, we have agreed to not issue any securities that are subject to a price reset based on the trading prices of our Common Stock or upon a specified or contingent event in the future, or enter into any agreement to issue securities at a future determined price for a period of one year following the closing date of this offering.

Regulation M

The placement agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the resale of the securities sold by it while acting as principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the placement agent would be required to comply with the requirements of the Securities Act and the Exchange Act, including, without limitation, Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of common shares by Wainwright acting as principal. Under these rules and regulations, the placement agent:

Other Relationships

From time to time, the placement agent has provided and may provide in the future, various advisory, investment and commercial banking and other services to us in the ordinary course of business, for which it may receive customary fees and commissions. The placement agent acted as our exclusive placement agent for the registered direct offerings we consummated in December 2022 and February 2023 and a sales agent in connection with our ATM, for which it received or may in the future receive compensation. Except as disclosed in this prospectus supplement, we have no present arrangements with the placement agent for any services.

Listing of Common Stock

Our Common Stock is listed on the Nasdaq Capital Market under the symbol “CKPT.” There is no established public trading market for the Common Warrants or the Placement Agent Warrants, and we do not expect a market to develop.

LEGAL MATTERS

Certain legal matters in connection with this offering and the validity of the securities offered by this prospectus will be passed upon for us by Alston & Bird LLP, New York, New York.

EXPERTS

The financial statements as of December 31, 2022 and 2021 and for each of the two years in the period ended December 31, 2022 incorporated by reference in this prospectus supplement have been so incorporated in reliance on the report of BDO USA, LLP, an independent registered public accounting firm, for the year ended December 31, 2021, incorporated herein by reference, and KPMG LLP, an independent registered public accounting firm, for the year ended December 31, 2022, incorporated herein by reference, given on the authority of said firms as experts in auditing and accounting.

As of July 15, 2022, KPMG LLP was engaged as our registered independent public accounting firm.

WHERE YOU CAN FIND MORE INFORMATION

We file reports with the SEC on an annual basis using Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K. The SEC maintains a website that contains annual, quarterly, and current reports, proxy statements, and other information that issuers (including us) file electronically with the SEC. The SEC’s website address is www.sec.gov. You can also obtain copies of materials we file with the SEC from our internet website found at www.checkpointtx.com. Our stock is quoted on the Nasdaq Capital Market under the symbol “CKPT.”

This prospectus supplement is only part of a registration statement on Form S-3 that we have filed with the SEC under the Securities Act 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 supplement, and you should refer to the applicable exhibit or schedule for a complete description of any statement referring to any contract or other document. You may inspect a copy of the registration statement, including the exhibits and schedules, without charge, at the SEC’s website.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents instead of having to repeat the information in this prospectus supplement and accompanying prospectus. The information incorporated by reference is considered to be part of this prospectus supplement and accompanying prospectus, and later information that we file with the SEC will automatically update and supersede this information. This prospectus supplement incorporates by reference the documents listed below (other than, unless otherwise specifically indicated, current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items):

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus supplement and deemed to be part of this prospectus supplement from the date of the filing of such reports and documents.

We will provide to each person, including any beneficial owner, to whom a copy of this prospectus supplement and the related prospectus is delivered, a copy of any or all of the information that we have incorporated by reference into this prospectus supplement and the related prospectus, but not delivered with this prospectus supplement and the related prospectus. We will provide this information upon written or oral request at no cost to the requester. You may request this information by contacting our corporate headquarters at the following address: 95 Sawyer Road, Suite 110, Waltham, Massachusetts 02453, Attn: Chief Financial Officer, or by calling (781) 652-4500.

PROSPECTUS

$100,000,000

Common Stock
Warrants
Debt Securities
Units

We may offer and sell an indeterminate number of shares of our common stock, warrants to purchase common stock, debt securities, or units representing some or all of these securities from time to time under this prospectus. You should read this prospectus and any prospectus supplement carefully before you invest.

We may offer our securities in one or more offerings in amounts, at prices, and on terms determined at the time of the offering. We may sell our securities through agents we select or through underwriters and dealers we select. If we use agents, underwriters or dealers, we will name them and describe their compensation in a prospectus supplement.

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

Our common stock is listed for trading on the Nasdaq Capital Market under the symbol CKPT.

We are an “emerging growth company” as defined in the Jumpstart Our Business Startups Act and will therefore be subject to reduced reporting requirements.

Investing in our securities involves risks. See “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2019, which has been filed with the U.S. Securities and Exchange Commission and are incorporated by reference into this prospectus. You should read this entire prospectus carefully before you make your investment decision.

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

The date of this prospectus is December 17, 2020.

TABLE OF CONTENTS

CHECKPOINT THERAPEUTICS, INC.

Our business

We are a clinical-stage immunotherapy and targeted oncology company focused on the acquisition, development and commercialization of novel treatments for patients with solid tumor cancers. We are evaluating our lead antibody product candidate, cosibelimab, an anti-programmed death-ligand 1 (“PD-L1”) antibody licensed from the Dana-Farber Cancer Institute, in an ongoing global, open-label, multicohort Phase 1 clinical trial in checkpoint therapy-naïve patients with selected recurrent or metastatic cancers, including ongoing cohorts in locally advanced and metastatic cutaneous squamous cell carcinoma intended to support one or more applications for marketing approval. In addition, we are evaluating our lead small-molecule, targeted anti-cancer agent, CK-101, a third-generation epidermal growth factor receptor (“EGFR”) inhibitor, as a potential new treatment for patients with EGFR mutation-positive non-small cell lung cancer (“NSCLC”).

We have also entered into various collaboration agreements with TG Therapeutics, Inc. (“TGTX”), a related party, to develop and commercialize certain assets in connection with our licenses in the field of hematological malignancies, while we retain the right to develop and commercialize these assets in solid tumors.

To date, we have not received approval for the sale of any product candidate in any market and, therefore, have not generated any product sales from any product candidates. In addition, we have incurred substantial operating losses since our inception, and expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of September 30, 2020, we have an accumulated deficit of $133.0 million.

We are a majority-controlled subsidiary of Fortress Biotech, Inc. (“Fortress”).

Our products under development

Immuno-Oncology Agents

Cosibelimab (Anti-PD-L1) Program

Cosibelimab (formerly referred to as CK-301) is a fully-human monoclonal antibody of IgG1 subtype that directly binds to PD-L1 and blocks the PD-L1 interaction with the Programmed Death Receptor-1 (“PD-1”) and B7.1 receptors. Cosibelimab’s primary mechanism of action is based on the inhibition of the interaction between PD-L1 and its receptors PD-1 and B7.1, which removes the suppressive effects of PD-L1 on anti-tumor CD8+ T-cells to restore the cytotoxic T cell response.

Numerous preclinical and clinical studies of third-parties have demonstrated that antibodies that block the interaction of PD-1 with its ligands, PD-L1 and PD-L2, or those that block only the interaction of PD-L1 with PD-1 can augment anti-tumor T-cell responses and lead to complete and lasting tumor eradication in a certain proportion of patients. Confirmed overall response rates (“ORRs”) in the labels for the Food and Drug Administration (“FDA”) approved PD-1 and PD-L1 blocking antibodies were cited in the 20-45% range based on clinical trials in patients with metastatic melanoma and NSCLC. Potent therapeutic anti-tumor responses due to blocking of PD-1/PD-L1 interaction have been demonstrated by these approved products in patients with various solid tumors including, but not limited to, NSCLC, melanoma, RCC, head and neck cancer, cutaneous squamous cell carcinoma (“CSCC”) and urothelial carcinoma.

We are developing cosibelimab in solid tumor oncology indications where studies of other PD-1/PD-L1 antibodies have shown to be effective. We licensed the exclusive worldwide rights to certain anti-PD-L1 antibodies from Dana-Farber Cancer Institute in March 2015. Also in March 2015, we entered into a Global Collaboration Agreement with TGTX, a related party, to develop and commercialize anti-PD-L1 antibodies in the field of hematological malignancies. We retain the right to develop and commercialize our anti-PD-L1 antibodies in solid tumors. We believe that cosibelimab has the potential to be effective in many oncological indications as a monotherapy or in combination with other anti-tumor immune response potentiating compounds and targeted therapies.

We commenced a Phase 1 multi-center clinical study for cosibelimab in October 2017. The study is evaluating the safety and tolerability of ascending doses of cosibelimab in checkpoint therapy-naïve patients with selected recurrent or metastatic cancers. Following completion of dose escalation in March 2018, multiple dose expansion cohorts were initiated. In September 2020, we announced updated interim results from our ongoing Phase 1 clinical trial of cosibelimab. The data were presented in a poster presentation at the ESMO Virtual Congress 2020. We continue to enroll CSCC patients to support one or more biologics license application (“BLA”) submissions to the FDA for cosibelimab based on this ongoing clinical trial. The primary endpoint is ORR, and secondary endpoints include duration of response, progression-free survival (“PFS”), and overall survival.

CK-302 (Anti-GITR) Program

Our anti-GITR monoclonal antibody, CK-302, is a fully human agonistic antibody that is designed to bind to and trigger signaling in GITR expressing cells. Scientific literature indicates that GITR is a co-stimulatory molecule of the TNF receptor family and is expressed on activated T cells, B cells, natural killer (“NK”) and regulatory T-cells (“Treg”). As a co-stimulatory molecule, GITR engagement increases proliferation, activation, and cytokine production of CD4+ and CD8+ T-cells. We believe our anti-GITR monoclonal antibody has the potential to abrogate immunosuppressive activity of natural Treg on expansion of T-effector cells. GITR-specific agonistic monoclonal antibodies under development by third parties have been shown to induce tumor regression in vivo through the activation of CD4+ T-cells, CD8+ T-cells and NK cells in a number of tumor models.

We are developing CK-302 for oncology indications where scientific literature supports the potential for an anti-GITR to be effective. We licensed the exclusive worldwide rights to anti-GITR antibodies from Dana-Farber Cancer Institute in March 2015. Also in March 2015, we entered into a Global Collaboration Agreement with TGTX to develop and commercialize anti-GITR antibodies in the field of hematological malignancies. We retain the right to develop and commercialize anti-GITR antibodies in solid tumors. We believe that an anti-GITR antibody has the potential to be effective in many oncological indications as a monotherapy or in combination with an anti-PD-L1 or anti-CAIX antibody as well as other anti-tumor immune response potentiating compounds and targeted therapies.

Currently, we are in preclinical development for this program.

Targeted Anti-Cancer Agents

CK-101 (also known as RX518) EGFR Inhibitor Program

We are developing CK-101 as an oral, third-generation, irreversible kinase inhibitor against selective mutations of EGFR. Activating mutations in the tyrosine kinase domain of EGFR such as L858R and exon 19 deletion are found in approximately 20% of patients with advanced NSCLC. Compared to chemotherapy, first-generation EGFR inhibitors significantly improved ORR and progression-free survival in previously untreated NSCLC patients carrying EGFR mutations. However, tumor progression could develop due to resistance mutations, often within months of treatment with first-generation EGFR inhibitors.

The EGFR T790M “gatekeeper” mutation is the most common resistance mutation found in patients treated with first-generation EGFR inhibitors. The mutation decreases the affinity of first-generation inhibitors to EGFR kinase domain, rendering the drugs ineffective. Second-generation EGFR inhibitors have improved in vitro potency against the T790M mutation, but have not provided meaningful benefits in NSCLC patients due to toxicity from also inhibiting wild-type EGFR.

Third-generation EGFR inhibitors are designed to be highly selective against the EGFR T790M mutation with minimal inhibition of wild-type EGFR, thereby improving tolerability and safety profiles. In November 2015, Tagrisso ^® (osimertinib), a third-generation EGFR tyrosine kinase inhibitor ("TKI") developed by AstraZeneca plc that specifically targets the EGFR activating and T790M resistance mutations, received accelerated FDA approval for the treatment of patients with metastatic EGFR T790M mutation-positive NSCLC who have progressed on or after receiving EGFR TKI therapy. Tagrisso received full approval from the FDA in 2017 based on data from a randomized, Phase 3 trial, in which Tagrisso significantly improved PFS versus platinum-based doublet chemotherapy, providing 10.1 months of median PFS compared to 4.4 months from chemotherapy.

In addition, third-generation inhibitors may also inhibit EGFR activating mutations seen in first-line NSCLC patients and have shown efficacy in monotherapy studies. In April 2018, Tagrisso received FDA approval for the first-line treatment of NSCLC patients with EGFR mutations based on data from a randomized, Phase 3 trial, in which Tagrisso significantly improved PFS versus first-generation EGFR inhibitors, providing 18.9 months of median PFS compared to 10.2 months from EGFR TKI comparators erlotinib or gefitinib.

We are developing CK-101 for the treatment of NSCLC patients carrying the susceptible EGFR mutations. These include EGFR L858R and exon 19 deletion mutations in first-line NSCLC patients as well as the EGFR T790M mutation in second-line NSCLC patients. We believe that CK-101 has the potential to be effective in these oncological indications as a monotherapy or in combination with other anti-tumor immune response potentiating compounds.

In March 2015, Fortress entered into an exclusive license agreement with NeuPharma, Inc., which agreement was assigned to us by Fortress on the same date, to develop and commercialize novel covalent third-generation EGFR inhibitors on a worldwide basis outside of certain Asian countries. In August 2016, the FDA accepted our IND application and we initiated a Phase 1/2 clinical trial in September 2016. The trial is evaluating the safety and tolerability of ascending doses of CK-101 in patients with advanced solid tumors to determine the maximum tolerated dose and the safety and efficacy of CK-101 in patients with EGFR mutation-positive NSCLC. In September 2018, we announced preliminary interim data from our ongoing clinical trial of CK-101. The data were presented in an oral presentation at the International Association for the Study of Lung Cancer 19th World Conference on Lung Cancer in Toronto. The trial is ongoing to identify the optimal dose to maximize therapeutic effect, following which a Phase 3 trial is planned to initiate in treatment-naïve EGFR mutation-positive NSCLC patients.

CK-103 BET Inhibitor Program

We are developing CK-103, a novel, selective and potent small molecule inhibitor of bromodomain and extra-terminal (“BET”) bromodomains. CK-103 binds to the first and second bromodomains (BD1, BD2) of the BET protein family, BRD2, BRD3, BRD4, and BRDT. A bromodomain is an amino acid protein domain that recognizes acetylated-lysine. The binding of the drug prevents interaction between BET proteins and both acetylated histones and transcription factors. Therefore, BET proteins, such as BRD4, are considered potential therapeutic targets in cancer, as they may play a pivotal role in regulating the transcription of key regulators of cancer cell growth and survival, including the c-Myc oncogene. BRD4 is often required for expression of c-Myc. Scientific literature has shown that small molecule inhibition of BET bromodomains may lead to selective killing of tumor cells across a broad range of hematologic malignancies and certain targeted solid tumors. We plan to develop CK-103 for the treatment of various advanced and metastatic solid tumor cancers, including, but not limited to, those associated with elevated c-Myc expression.

In May 2016, we entered into an exclusive license agreement with Jubilant Biosys Limited to develop and commercialize novel compounds that inhibit BET bromodomains on a worldwide basis. Also in May 2016, we entered into a Sublicense Agreement with TGTX to develop and commercialize CK-103 in the field of hematological malignancies. We retain the right to develop and commercialize CK-103 in solid tumors. We completed the required CMC, pharmacology and toxicology activities that we believe will support an IND application filing.

Anti-CAIX Research Program

Our anti-carbonic anhydrase IX (“CAIX”) antibody is a fully human preclinical antibody designed to recognize CAIX expressing cells and kill them via antibody-dependent cell-mediated cytotoxicity (“ADCC”) and complement-dependent cytotoxicity (“CDC”). Scientific literature indicates that CAIX is a well characterized tumor associated antigen with expression almost exclusively limited to the cells of renal cell carcinoma (“RCC”). More than 85% of RCC cases have been demonstrated to express high levels of CAIX expression. There is very limited expression of this antigen on healthy tissue which we believe will limit reactivity of this antibody against healthy tissues.

In 2015, preclinical data were published in the peer-reviewed journal, Molecular Cancer, that demonstrated that our anti-CAIX antibodies could trigger killing of CAIX-positive human RCC cell lines in tissue culture via ADCC and CDC. The killing activity correlated positively with the level of CAIX expression on RCC tumor cell lines. In addition, the study demonstrated that our anti-CAIX antibodies inhibited growth of CAIX-positive tumors in a mouse xenograft model as well as led to the activation of T-cells and NK cells.

We plan to develop an anti-CAIX antibody for the treatment of patients with RCC in combination with an anti-PD-L1 and/or anti-GITR antibody as well as potentially other anti-tumor immune response potentiating compounds and/or targeted therapies.

We licensed the exclusive worldwide rights to certain anti-CAIX antibodies from Dana-Farber Cancer Institute in March 2015. Currently, we are in preclinical development for this program.

Company information

Our principal executive offices are located at 2 Gansevoort St., 9^th Floor, New York, New York 10014, and our telephone number is (781) 652-4500. We maintain a website on the Internet at www.checkpointtx.com and our e-mail address is ir@checkpointtx.com. Our internet website, and the information contained on it, are not to be considered part of this prospectus. For further information regarding us and our financial information, you should refer to our recent filings with the SEC. See “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

IMPORTANT INFORMATION ABOUT THIS PROSPECTUS

In this prospectus, unless the context suggests otherwise, references to “Checkpoint Therapeutics,” “Checkpoint,” the “Company,” “we,” “us” and “our” refer to Checkpoint Therapeutics, Inc.

This prospectus is part of a “shelf” registration statement that we filed with the SEC. By using a shelf registration statement, we may sell our securities, as described in this prospectus, from time to time in one or more offerings. We may use the shelf registration statement to offer and sell securities described in this prospectus. Each time we sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the terms of such offering. The prospectus supplement may also add, update or change information contained in this prospectus. Before purchasing any securities, you should carefully read both this prospectus and any prospectus supplement, together with the additional information incorporated into this prospectus or described under the heading “Where You Can Find More Information.”

You should rely only on the information contained or incorporated by reference in this prospectus and any prospectus supplement. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We will not make an offer to sell securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus, as well as information we previously filed with the Securities and Exchange Commission (“SEC”) and have incorporated by reference, is accurate as of the date on the front cover of this prospectus only, or when such document was filed with the SEC. Our business, financial condition, results of operations and prospects may have changed since the relevant date.

Neither we, nor any of our officers, directors, agents or representatives or underwriters, make any representation to you about the legality of an investment. You should not interpret the contents of this prospectus, any prospectus supplement, or any free writing prospectus to be legal, business, investment or tax advice. You should consult with your own advisors for that type of advice and consult with them about the legal, tax, business, financial and other issues that you should consider before investing in our common stock.

We will not use this prospectus to offer and sell securities unless it is accompanied by a prospectus supplement that more fully describes the terms of the offering.

Solely for convenience, tradenames referred to in this prospectus, the accompanying prospectus and the documents incorporated by reference may appear without the ® or TM symbol, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these tradenames.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

DESCRIPTION OF CAPITAL STOCK

The following description summarizes the material terms of Checkpoint capital stock as of the date of this registration statement. Because it is only a summary, it does not contain all the information that may be important to you. For a complete description of our capital stock, you should refer to our certificate of incorporation, our bylaws and to the provisions of applicable Delaware law.

Our common stock is traded on The Nasdaq Capital Market, or the Exchange, under the symbol “CKPT.” The last reported sale price of our common stock on November 25, 2020 was $2.42 per share.

The authorized capital stock of Checkpoint consists of 95,000,000 shares of common stock, of which 7,000,000 shares have been designated as Class A common stock. The description of our Class A Common Stock in this item is for information purposes only. All of the Class A common stock has been issued to Fortress. Class A common stock is identical to common stock other than as to voting rights, the election of directors for a definite period, and conversion rights. On any matter presented to our stockholders for their action or consideration at any meeting of our stockholders (or by written consent of stockholders in lieu of meeting), each holder of outstanding shares of Class A common stock will be entitled to cast for each share of Class A common stock held by such holder as of the record date for determining stockholders entitled to vote on such matter, the number of votes that is equal to one and one-tenth (1.1) times a fraction, the numerator of which is the sum of the shares of outstanding common stock and the denominator of which is the number of shares of outstanding Class A common stock. Thus, the Class A common stock will at all times constitute a voting majority. For a period of ten (10) years from the date of the first issuance of shares of Class A common stock (the “Class A Director Period”), the holders of record of the shares of Class A common stock (or other capital stock or securities issued upon conversion of or in exchange for the Class A common stock), exclusively and as a separate class, will be entitled to appoint or elect the majority of the directors of Checkpoint (the “Class A Directors”). Finally, each share of Class A common stock is convertible, at the option of the holder, into one fully paid and nonassessable share of common stock (the “Conversion Ratio”), subject to certain adjustments.

If Checkpoint at any time effects a subdivision of the outstanding common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) by any stock split, stock dividend, recapitalization or otherwise, the applicable Conversion Ratio in effect immediately before that subdivision will be proportionately decreased so that the number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) issuable on conversion of each share of Class A common stock will be increased in proportion to such increase in the aggregate number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) outstanding. If Checkpoint at any time combines the outstanding shares of common stock, the applicable Conversion Ratio in effect immediately before the combination will be proportionately increased so that the number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) issuable on conversion of each share of Class A common stock will be decreased in proportion to such decrease in the aggregate number of shares of common stock (or other capital stock or securities at the time issuable upon conversion of the Class A common stock) outstanding. Additionally, if any reorganization, recapitalization, reclassification, consolidation or merger involving Checkpoint occurs in which the common stock (but not the Class A common stock) is converted into or exchanged for securities, cash or other property (other than a transaction involving the subdivision or combination of the common stock), then, following any such reorganization, recapitalization, reclassification, consolidation or merger, each share of Class A common stock becomes convertible into the kind and amount of securities, cash or other property which such Class A Stockholder would have been entitled to receive had he or she converted the Class A Shares immediately before said transaction. In such case, appropriate adjustment (as determined in good faith by the Board of Directors of Checkpoint) will be made in the application of the provisions of Checkpoint’s Amended and Restated Certificate of Incorporation relating the subdivision or combination of the common stock with respect to the rights and interests thereafter of the holders of the Class A common stock, such that the provisions set forth in of Checkpoint’s Amended and Restated Certificate of Incorporation relating to the subdivision or combination of the common stock (including the provisions with respect to changes in and other adjustments of the applicable Conversion Ratio) will thereafter be applicable, as nearly as reasonably may be, in relation to any securities or other property thereafter deliverable upon the conversion of the Class A common stock. Checkpoint is not authorized to issue preferred stock.

Other features of our common stock include:

DESCRIPTION OF WARRANTS

We may issue warrants to purchase shares of our common stock in one or more series together with other securities or separately, as described in each applicable prospectus supplement.

The prospectus supplement relating to any warrants we offer will include specific terms relating to the offering. These terms will include some or all of the following:

DESCRIPTION OF DEBT SECURITIES

We may offer debt securities which may be senior, subordinated or junior subordinated and may be convertible. Unless otherwise specified in the applicable prospectus supplement, our debt securities will be issued in one or more series under an indenture to be entered into between us and a trustee. We will issue the debt securities offered by this prospectus and any accompanying prospectus supplement under an indenture to be entered into between us and the trustee identified in the applicable prospectus supplement. The terms of the debt securities will include those stated in the indenture and those made part of the indenture by reference to the Trust Indenture Act of 1939, as in effect on the date of the indenture. We have filed a copy of the form of indenture as an exhibit to the registration statement in which this prospectus is included. The indenture will be subject to and governed by the terms of the Trust Indenture Act of 1939.

The following description briefly sets forth certain general terms and provisions of the debt securities that we may offer. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which these general provisions may apply to the debt securities, will be described in the related prospectus supplement. Accordingly, for a description of the terms of a particular issue of debt securities, reference must be made to both the related prospectus supplement and to the following description.

Debt Securities

The aggregate principal amount of debt securities that may be issued under the indenture is unlimited. The debt securities may be issued in one or more series as may be authorized from time to time pursuant to a supplemental indenture entered into between us and the trustee or an order delivered by us to the trustee. For each series of debt securities we offer, a prospectus supplement accompanying this prospectus will describe the following terms and conditions of the series of debt securities that we are offering, to the extent applicable:

General

One or more series of debt securities may be sold as “original issue discount” securities. These debt securities would be sold at a substantial discount below their stated principal amount, bearing no interest or interest at a rate which at the time of issuance is below market rates. One or more series of debt securities may be variable rate debt securities that may be exchanged for fixed rate debt securities.

United States federal income tax consequences and special considerations, if any, applicable to any such series will be described in the applicable prospectus supplement.

Debt securities may be issued where the amount of principal and/or interest payable is determined by reference to one or more currency exchange rates, commodity prices, equity indices or other factors. Holders of such debt securities may receive a principal amount or a payment of interest that is greater than or less than the amount of principal or interest otherwise payable on such dates, depending upon the value of the applicable currencies, commodities, equity indices or other factors. Information as to the methods for determining the amount of principal or interest, if any, payable on any date, the currencies, commodities, equity indices or other factors to which the amount payable on such date is linked and certain additional United States federal income tax considerations will be set forth in the applicable prospectus supplement.

The term “debt securities” includes debt securities denominated in U.S. dollars or, if specified in the applicable prospectus supplement, in any other freely transferable currency or units based on or relating to foreign currencies.

We expect most debt securities to be issued in fully registered form without coupons and in denominations of $2,000 and any integral multiples thereof. Subject to the limitations provided in the indenture and in the prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the principal corporate trust office of the trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

Global Securities

The debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the prospectus supplement. Global securities will be issued in registered form and in either temporary or definitive form. Unless and until it is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a nominee of such successor. The specific terms of the depositary arrangement with respect to any debt securities of a series and the rights of and limitations upon owners of beneficial interests in a global security will be described in the applicable prospectus supplement.

Governing Law

The indenture and the debt securities shall be construed in accordance with and governed by the laws of the State of New York.

DESCRIPTION OF UNITS

We may issue, in one more series, units comprised of shares of our common stock, warrants to purchase common stock, debt securities or any combination of those securities. 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 included security. 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 may evidence units by unit certificates that we issue under a separate agreement. We may issue the units under a unit agreement between us and one or more unit agents. If we elect to enter into a unit agreement with a unit agent, the unit agent will act solely as our agent in connection with the units and will not assume any obligation or relationship of agency or trust for or with any registered holders of units or beneficial owners of units. We will indicate the name and address and other information regarding the unit agent in the applicable prospectus supplement relating to a particular series of units if we elect to use a unit agent.

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

The other provisions regarding our common stock, warrants and debt securities as described in this section will apply to each unit to the extent such unit consists of shares of our common stock, warrants and/or debt securities.

PLAN OF DISTRIBUTION

We may sell the securities covered in this prospectus in any of three ways (or in any combination):

Each time that we use this prospectus to sell securities, we will also provide a prospectus supplement that contains the specific terms of the offering. The prospectus supplement will set forth the terms of the offering of the securities, including:

Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

If underwriters are used in the sale of any securities, the securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The securities may be either offered to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters. Generally, the underwriters’ obligations to purchase the securities will be subject to certain conditions precedent. The underwriters will be obligated to purchase all of the securities if they purchase any of securities.

We may sell the securities through agents from time to time. The prospectus supplement will name any agent involved in the offer or sale of the securities and any commissions we pay to them. Generally, any agent will be acting on a best efforts basis for the period of its appointment.

We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we pay for solicitation of these contracts.

Agents and underwriters may be entitled to indemnification by us against certain civil liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribution with respect to payments which the agents or underwriters may be required to make in respect thereof. Agents and underwriters may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of securities, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of securities. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement (or a post-effective amendment).

LEGAL MATTERS

Certain legal matters will be passed upon for us by Alston & Bird LLP, New York, New York. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The financial statements as of December 31, 2019 and 2018 and for each of the two years in the period ended December 31, 2019 incorporated by reference in this Prospectus and in the Registration Statement have been so incorporated in reliance on the report of BDO USA, LLP, an independent registered public accounting firm, incorporated herein by reference, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities offered hereby. This prospectus does not contain all of the information set forth in the registration statement and the exhibits and schedules thereto. For further information with respect to us and our securities, reference is made to the registration statement and the exhibits and any schedules filed therewith. Statements contained in this prospectus as to the contents of any contract or other document referred to are not necessarily complete and in each instance, if such contract or document is filed as an exhibit, reference is made to the copy of such contract or other document filed as an exhibit to the registration statement, each statement being qualified in all respects by such reference. The SEC maintains an internet site at www.sec.gov, from which interested persons can electronically access the registration statement, including the exhibits and any schedules thereto.

We are subject to the information reporting requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and we file periodic reports and other information with the SEC. All documents filed with the SEC are available for inspection at the internet addresses set forth above. We also maintain an internet site at www.checkpointtx.com. Our website and the information contained therein or connected thereto shall not be deemed to be incorporated into this prospectus or the registration statement of which it forms a part.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents instead of having to repeat the information in this prospectus and accompanying prospectus supplement. The information incorporated by reference is considered to be part of this prospectus and accompanying prospectus supplement, and later information that we file with the SEC will automatically update and supersede this information. This prospectus incorporates by reference the documents listed below (other than, unless otherwise specifically indicated, current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items):

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

 1,700,000 Shares of Common Stock

PROSPECTUS SUPPLEMENT

H.C. Wainwright & Co.

March 30, 2023