vxrt20260414

S-3 1 vxrt20260414_s3.htm FORM S-3 vxrt20260414_s3.htm

As filed with the Securities and Exchange Commission on April 15, 2026

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

VAXART, INC.

(Exact name of registrant as specified in its charter)

Delaware	59-1212264
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification Number)

310 Utah Avenue, Suite 150

South San Francisco, CA 94080

(650) 550-3500

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

Steven Lo

Chief Executive Officer

310 Utah Avenue, Suite 150

South San Francisco, CA 94080

(650) 550-3500

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Faith L. Charles
Thompson Hine LLP

300 Madison Avenue, 27th Floor

New York, NY 10017

(212) 908-3905

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Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.

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

If any of the securities being registered on this Form 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: ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, 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 Form 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 Form 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 Form 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, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☐	Accelerated filer	☒
Non-accelerated filer	☐	Smaller reporting company	☒
		Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act. ☐

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 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 SECTION 8(a), MAY DETERMINE.

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EXPLANATORY NOTE

This registration statement contains two documents:

●

a base prospectus which covers the offering, issuance, and sale by the registrant of up to a maximum aggregate offering price of $300,000,000 of the registrant’s common stock, preferred stock, debt securities, warrants, purchase contracts, and/or units; and

●

a sales agreement prospectus supplement covering the offering, issuance, and sale by the registrant of up to a maximum aggregate offering price of $49,772,479 of the registrant’s common stock that may be issued and sold under a sales agreement with Citizens JMP Securities, LLC and B. Riley Securities, Inc.

The base prospectus immediately follows this explanatory note. The sales agreement prospectus supplement immediately follows the base prospectus. The $49,772,479 of common stock that may be offered, issued, and sold by the registrant under the sales agreement prospectus supplement is included in the $300,000,000 of securities that may be offered, issued, and sold by the registrant under the base prospectus. Upon termination of the sales agreement with Citizens JMP Securities, LLC and B. Riley Securities, Inc., any portion of the $49,772,479 included in the sales agreement prospectus supplement that is not sold pursuant to the sales agreement will be available for sale in other offerings pursuant to the base prospectus, and if no shares are sold under the sales agreement, the full $300,000,000 of securities may be sold in other offerings pursuant to the base prospectus and a corresponding prospectus supplement.

The specific terms of any securities to be offered pursuant to the base prospectus other than the shares under the sales agreement will be specified in a prospectus supplement to the base prospectus. The specific terms of the securities to be issued and sold under the sales agreement are specified in the sales agreement prospectus that immediately follows the base prospectus.

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THE INFORMATION IN THIS PRELIMINARY 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 PRELIMINARY PROSPECTUS IS NOT AN OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY JURISDICTION WHERE THE OFFER OR SALE IS NOT PERMITTED.

SUBJECT TO COMPLETION, DATED APRIL 15, 2026

PROSPECTUS

$300,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Purchase Contracts

Units

We may offer and sell up to $300,000,000 in the aggregate of the securities identified above, from time to time in one or more offerings. This prospectus provides you with a general description of the securities.

Each time we offer and sell securities, we will provide one or more supplements to this prospectus that contains specific information about the offering, including the amounts, prices, and terms of the securities. The supplements may also add, update, or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and all applicable prospectus supplements, together with the documents we incorporate by reference, before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers, and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers, or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission, or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement to the extent appropriate or required by law. See the sections of this prospectus titled “About this Prospectus” and “Plan of Distribution” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

Our common stock is traded on the OTCQX® Best Market under the trading symbol “VXRT.” On April 10, 2026, the last reported sale price of our common stock on the OTCQX® Best Market was $0.63. As of April 10, 2026, there were 241,414,053 shares of our common stock outstanding.

INVESTING IN OUR SECURITIES INVOLVES A HIGH DEGREE OF RISK. SEE THE “RISK FACTORS” ON PAGE 2 OF THIS PROSPECTUS AND ANY SIMILAR SECTION CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT AND IN THE DOCUMENTS INCORPORATED BY REFERENCE HEREIN AND THEREIN CONCERNING FACTORS YOU SHOULD CONSIDER BEFORE INVESTING IN OUR SECURITIES.

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

The date of this prospectus is __________, 2026.

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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	i
PROSPECTUS SUMMARY	1
RISK FACTORS	2
THE SECURITIES WE MAY OFFER	3
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	4
USE OF PROCEEDS	5
DESCRIPTION OF COMMON STOCK	6
DESCRIPTION OF PREFERRED STOCK	7
DESCRIPTION OF DEBT SECURITIES	8
DESCRIPTION OF WARRANTS	10
DESCRIPTION OF PURCHASE CONTRACTS	12
DESCRIPTION OF UNITS	13
CERTAIN PROVISIONS OF DELAWARE LAW AND OF THE COMPANY’S CERTIFICATE OF INCORPORATION AND BYLAWS	14
LEGAL OWNERSHIP OF SECURITIES	16
PLAN OF DISTRIBUTION	19
LEGAL MATTERS	21
EXPERTS	21
WHERE YOU CAN FIND ADDITIONAL INFORMATION	21
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE	21

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the U.S. Securities and Exchange Commission (the “SEC”) utilizing a “shelf” registration process. Under this shelf registration statement process, we may offer shares of our common stock, preferred stock, various series of debt securities, warrants to purchase common stock or preferred stock, purchase contracts, and/or units to purchase any of such securities, either individually or in combination with other securities described in this prospectus, in one or more offerings from time to time, with a total value of up to $300,000,000. This prospectus provides you with a general description of the securities we may offer.

Each time we sell any type or series of securities under this prospectus, we will provide a prospectus supplement that will include more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update, or change any of the information contained in this prospectus or in the documents we have incorporated by reference into this prospectus. This prospectus, together with the applicable prospectus supplement, any related free writing prospectus, and the documents incorporated by reference into this prospectus and the applicable prospectus supplement, will include all material information relating to the applicable offering. Before buying any of the securities being offered, we urge you to carefully read this prospectus, all applicable prospectus supplements, and any related free writing prospectuses we have authorized for use in connection with a specific offering, together with the additional information incorporated herein by reference as described under the heading “Incorporation of Certain Information by Reference.”

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

You should rely only on the information contained in, or incorporated by reference into, this prospectus and the applicable prospectus supplement, along with the information contained in any free writing prospectuses we have authorized for use in connection with a specific offering. We have not authorized anyone to provide you with different or additional information. No dealer, salesperson, or other person is authorized to give any information or to represent anything not contained or incorporated by reference in this prospectus, any applicable prospectus supplement, or any related free writing prospectus that we may authorize to be provided to you. This prospectus is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

You should assume that the information in this prospectus, any applicable prospectus supplement, or any related free writing prospectus is accurate only as of the date on the front of the document and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, any applicable prospectus supplement, or any related free writing prospectus, or any sale of our securities. Our business, financial condition, results of operations, and prospects may have changed since that date.

This prospectus includes summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed, or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described in the section titled “Where You Can Find Additional Information.”

The following summary highlights information contained elsewhere in this prospectus or incorporated by reference herein and does not contain all the information that may be important to purchasers of our securities. You should carefully read this prospectus, all documents incorporated by reference, any prospectus supplement and any related free writing prospectus, and the additional information described in the “Where You Can Find Additional Information” section of this prospectus, before buying any of the securities being offered. References in this prospectus to “Vaxart,” the “Company,” “we,” “us,” and “our” refer to Vaxart, Inc. and its subsidiaries, on a consolidated basis, unless the context requires otherwise.

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PROSPECTUS SUMMARY

This summary highlights selected information contained elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus and accompanying base prospectus, and any related free writing prospectus, including the risks of investing in our securities discussed in the section titled “Risk Factors” contained in this prospectus, the base prospectus, and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

Our Company

We are a clinical-stage biotechnology company primarily focused on the development of oral recombinant vaccines based on our Vector-Adjuvant-Antigen Standardized Technology (“VAAST”) proprietary oral vaccine platform. We are developing prophylactic vaccine candidates that target a range of infectious diseases, including norovirus (a widespread cause of acute gastroenteritis), coronavirus including SARS-CoV-2 (the virus that causes coronavirus disease 2019 (“COVID-19”)), and influenza. In addition, we have generated preclinical data for our first therapeutic vaccine candidate targeting cervical cancer and dysplasia caused by human papillomavirus (“HPV”). Our oral vaccines are designed to generate broad and durable immune responses that may protect against a wide range of infectious diseases and may be useful for the treatment of chronic viral infections and cancer. Our investigational vaccines are administered using a room temperature-stable tablet, rather than by injection.

Corporate History and Reorganization

Vaxart Biosciences, Inc. was originally incorporated in California under the name West Coast Biologicals, Inc. in March 2004 and changed its name to Vaxart, Inc. (“Private Vaxart”) in July 2007, when it reincorporated in the state of Delaware.

On February 13, 2018, Private Vaxart completed a reverse merger (the “Merger”) with Aviragen Therapeutics, Inc. (“Aviragen”), pursuant to which Private Vaxart survived as a wholly owned subsidiary of Aviragen. Under the terms of the Merger, Aviragen changed its name to Vaxart, Inc. and Private Vaxart changed its name to Vaxart Biosciences, Inc. Our common stock subsequently began trading on The Nasdaq Capital Market under the symbol “VXRT.” In November 2025, our common stock was delisted from Nasdaq. In July 2025, our common stock began being traded publicly on the on the OTCQX® Best Market under the trading symbol “VXRT.”

Our corporate headquarters and laboratory are located at 310 Utah Avenue, Suite 150, South San Francisco, California 94080, and our telephone number is (650) 550-3500. We maintain a website at https://www.vaxart.com, to which we regularly post copies of our press releases as well as additional information about us. The information contained on, or that can be accessed through, our website is not a part of this prospectus or the accompanying prospectus supplement. We have included our website address in this prospectus solely as an inactive textual reference.

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RISK FACTORS

Investing in our securities involves a high degree of risk. Prior to making a decision about investing in our securities, you should carefully consider the specific risk factors discussed in the sections titled “Risk Factors” contained in our annual report on Form 10-K for the fiscal year ended December 31, 2025 under the heading “Item 1A. Risk Factors,” and as described or may be described in any subsequent quarterly reports on Form 10-Q under the heading “Item 1A. Risk Factors,” as well as in all applicable prospectus supplements and contained or to be contained in our filings with the SEC and incorporated by reference in this prospectus, together with all of the other information contained in this prospectus, and any applicable prospectus supplement. For a description of these reports and documents, and information about where you can find them, see “Where You Can Find Additional Information” and “Incorporation of Certain Information by Reference.” If any of the risks or uncertainties described in our SEC filings or any prospectus supplement or any additional risks and uncertainties actually occur, our business, financial condition, and results of operations could be materially and adversely affected. In that case, the trading price of our securities could decline and you might lose all or part of the value of your investment.

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THE SECURITIES WE MAY OFFER

Under this prospectus, we may offer shares of our common stock, preferred stock, various series of debt securities, warrants to purchase common stock or preferred stock, purchase contracts, and/or units to purchase any of such securities, either individually or in combination with other securities described in this prospectus, in one or more offerings from time to time at prices and on terms to be determined by market conditions at the time of the offering. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities, we will provide a prospectus supplement that will describe the specific amounts, prices, and other important terms of the securities, including, to the extent applicable:

	●	designation or classification;

	●	aggregate principal amount or aggregate offering price;

	●	maturity, if applicable;

	●	rates and times of payment of interest or dividends, if any;

	●	redemption, conversion or sinking fund terms, if any;

	●	voting or other rights, if any; and

	●	conversion or exercise prices, if any.

A prospectus supplement and any related free writing prospectus that we may authorize to be provided to you also may add, update, or change information contained in this prospectus or in documents we have incorporated by reference.

This prospectus may not be used to offer or sell securities unless it is accompanied by a prospectus supplement.

We may sell the securities directly to or through agents, underwriters, or dealers. We, and our agents, underwriters, or dealers, reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities through agents or underwriters, we will include in the applicable prospectus supplement:

	●	the names of those agents or underwriters;

	●	applicable fees, discounts, and commissions to be paid to them;

	●	details regarding over-allotment options, if any; and

	●	the net proceeds to us.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents we have filed with the SEC that are incorporated by reference contain “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Exchange Act. These statements relate to future events or to our future operating or financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements may include, but are not limited to, statements relating to:

	●	our ability to develop and commercialize our product candidates and clinical results and trial data;

	●	our ability to negotiate and receive royalty payments on the sales of our product candidates including Inavir;

	●	our ability to obtain the various synergies envisioned in the Exclusive License and Collaboration Agreement with Dynavax Technologies Corporation;

	●	estimates of selected financial results for future time periods;

	●	our ability to obtain, maintain, and enforce necessary patent and other intellectual property protection;

	●	potential partnership opportunities;

	●	expectations regarding the future contributions of our management team;

	●	the ability of our management team to build out the Company and drive sustainable growth and value creation;

	●	our ability to manufacture vaccine tablets;

	●	expectations regarding clinical results and trial data;

	●	expectations regarding the effectiveness, safety, or convenience of our norovirus vaccine candidate;

	●	expectations regarding the effectiveness, safety, or convenience of any other vaccine candidate;

	●	the anticipated use of proceeds from this offering; and

	●	our expectations with respect to the important advantages we believe our oral vaccine platform can offer over injectable alternatives.

In some cases, you can identify forward-looking statements by terms such as “anticipates,” “believes,” “could,” “estimates,” “intends,” “may,” “plans,” “potential,” “will,” “would,” or the negative of these terms or other similar expressions. These statements reflect our current views with respect to future events and are based on assumptions and are subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements. We discuss in greater detail many of these risks in the section titled “Risk Factors”, in any prospectus supplement and free writing prospectuses we may authorize for use in connection with this offering, and in our most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

You should read this prospectus, together with the documents we have filed with the SEC that are incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities as set forth in the applicable prospectus supplement.

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DESCRIPTION OF COMMON STOCK

The following summary of certain provisions of our common stock does not purport to be complete. You should refer to the section of this prospectus titled “Certain Provisions of Delaware Law and of the Company’s Certificate of Incorporation and Bylaws” and to our restated certificate of incorporation, as amended from time to time (the “Charter”), our amended and restated bylaws (the “Bylaws”), and the applicable provisions of the Delaware General Corporation Law (the “DGCL”). This information is qualified entirely by reference to the applicable provisions of our Charter, Bylaws, and the DGCL.

General

We are authorized to issue 350,000,000 shares of common stock, par value $0.0001 per share. As of the date of this prospectus, there were 241,414,053 shares of our common stock outstanding.

The following is a summary of the material provisions of the common stock provided for in our Charter and Bylaws.

Voting

Our common stock is entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders. However, directors are elected by a plurality of the votes cast. Accordingly, the holders of a majority of the shares of common stock entitled to vote in any election of directors are able to elect all of the directors standing for election, if they so choose.

Dividends

Subject to preferences that may be applicable to any then outstanding preferred stock, the holders of common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds. We have never paid cash dividends and have no present intention to pay cash dividends.

Liquidation

In the event of a liquidation, dissolution or winding up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.

Rights and Preferences

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. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we have designated or issued, or may designate and issue in the future.

Fully Paid and Nonassessable

All of our outstanding shares of common stock are fully paid and nonassessable.

Nasdaq Capital Market Listing

Our common stock is listed on the OTCQX® Best Market under the symbol “VXRT.”

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Equiniti Trust Company, LLC. The transfer agent and registrar's address is 6201 15th Avenue, Brooklyn, New York 11219.

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DESCRIPTION OF PREFERRED STOCK

The following summary of certain provisions of our common stock does not purport to be complete. You should refer to the section of this prospectus titled “Certain Provisions of Delaware Law and of the Company’s Certificate of Incorporation and Bylaws” and to our Charter, our Bylaws, and the applicable provisions of the DGCL. This information is qualified entirely by reference to the applicable provisions of our Charter, Bylaws, and the DGCL. The rights, preferences, privileges and restrictions of the preferred stock of each series will be fixed by the certificate of designation relating to that series.

General

We are authorized, without action by the stockholders, to designate and issue up to 5,000,000 shares of preferred stock, par value $0.0001 per share. As of the date of this prospectus, there were no shares of our preferred stock outstanding.

Our board of directors has the authority, subject to limitations prescribed by Delaware law, to issue preferred stock in one or more series, to establish from time to time the number of shares to be included in each series, and to fix or alter the rights, preferences and privileges of the preferred stock, along with any limitations or restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences of each class or series of preferred stock.

Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of common stock. The issuance of preferred stock, while providing flexibility in connection with possible future financings and acquisitions and other corporate purposes could, under certain circumstances, have the effect of restricting dividends on our common stock, diluting the voting power of our common stock, impairing the liquidation rights of our common stock, or delaying, deferring, or preventing a change in control of our Company, which might harm the market price of our common stock. See also “Certain Provisions of Delaware Law and of the Company’s Certificate of Incorporation and Bylaws — Anti-Takeover Provisions.”

Each series of preferred stock, if issued, will be more fully described in the particular prospectus supplement that will accompany this prospectus. To the extent required, this description will include:

	●	the maximum number of shares;

	●	the designation of the shares;

	●	the annual dividend rate, if any, whether the dividend rate is fixed or variable, the date or dates on which dividends will accrue, the dividend payment dates, and whether dividends will be cumulative;

	●	the price and the terms and conditions for redemption, if any, including redemption at the option of the Company or at the option of the holders, including the time period for redemption, and any accumulated dividends or premiums;

	●	the liquidation preference, if any, and any accumulated dividends upon the liquidation, dissolution or winding up of our affairs;

	●	any sinking fund or similar provision, and, if so, the terms and provisions relating to the purpose and operation of the fund;

	●	the terms and conditions, if any, for conversion or exchange of shares of any other class or classes of our capital stock or any series of any other class or classes, or of any other series of the same class, or any other securities or assets, including the price or the rate of conversion or exchange and the method, if any, of adjustment;

	●	the voting rights, if any; and

	●	any or all other preferences and relative, participating, optional or other special rights, privileges or qualifications, limitations or restrictions.

Transfer Agent and Registrar

The transfer agent and registrar for any series of preferred stock that is designated by our board of directors will be set forth in the applicable prospectus supplement.

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DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplement or free writing prospectus, summarizes certain general 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, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities we offer under a prospectus supplement may differ from the terms described below.

As of the date of this prospectus, we have no debt securities issued and outstanding.

We may sell from time to time, in one or more offerings under this prospectus, secured or unsecured debt securities, which may be senior or subordinated. Any subordinated debt securities generally will be entitled to payment only after payment of our senior debt. Senior debt generally includes all debt for money borrowed by us, except debt that is stated in the instrument governing the terms of that debt to be not senior to, or to have the same rank in right of payment as, or to be expressly junior to, the subordinated debt securities. We may issue debt securities that are convertible into shares of our common stock or preferred stock.

We will issue any debt securities under an indenture, which we will enter into with the trustee named in the indenture. Any indenture will be qualified under the Trust Indenture Act of 1939, as amended. You should read the summary below, the applicable prospectus supplement and the provisions of the applicable indenture and any related security documents, if any, in their entirety before investing in our debt securities.

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

	●	the title or designation;

	●	the principal amount being offered, and if a series, the total amount authorized and the total amount out-standing;

	●	any limit on the amount that may be issued;

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

	●	the maturity date;

	●	the principal amount due at maturity, and whether the debt securities will be issued with an original issue discount;

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

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

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

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

	●	the place where payments will be payable;

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

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

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

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

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

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

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

	●	information describing any book-entry features;

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

	●	any provisions for payment of additional amounts for taxes and any provision for redemption, if we must pay such additional amount with respect to any debt security;

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

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

	●	the terms on which a series of debt securities may be convertible into or exchangeable for our common stock, any other of our securities or securities of a third party, and whether conversion or exchange is mandatory, at the option of the holder or at our option;

	●	events of default;

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

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

	●	descriptions of the debenture trustee and paying agent, and the method of payments; and

	●	any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants provided with respect to the debt securities, and any terms which may be required by us or advisable under applicable laws or regulations.

Specific indentures will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus, or as an exhibit to a report filed under the Exchange Act, incorporated by reference in this prospectus.

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DESCRIPTION OF WARRANTS

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

We may issue warrants for the purchase of common stock or preferred stock or debt securities, in one or more series. We may issue warrants independently or together with common stock, preferred stock, debt securities, or other securities, and the warrants may be attached to or separate from our common stock, preferred stock, debt securities, or other securities.

We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant agreement, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering before the issuance of the related series of warrants. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectuses, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.

General

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

	●	the offering price and aggregate number of warrants offered;

	●	the currency for which the warrants may be purchased;

	●	if applicable, the number of warrants issued with each share of common stock or preferred stock, or with the principal amount of any debt security;

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

	●	the number of shares of common stock, preferred stock, or debt securities purchasable upon the exercise of one warrant and the price at which these shares or debt may be purchased upon such exercise;

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

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

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

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

	●	the various factors considered in determining the exercise or conversion price of the warrants;

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	●	the manner in which the warrant agreements and warrants may be modified; and

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

Before exercising their warrants, holders of warrants will not have any of the rights of holders of common stock or preferred stock purchasable upon such exercise, including the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights.

Exercise of Warrants

Each warrant will entitle the holder to purchase the number of shares of common stock or preferred stock or principal amount of debt securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

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

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

Governing Law

Unless we provide otherwise in the applicable prospectus supplement, the warrants and warrant agreements will be governed by and construed in accordance with the laws of the State of Delaware.

Enforceability of Rights by Holders of Warrants

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

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DESCRIPTION OF PURCHASE CONTRACTS

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

We may issue purchase contracts for the purchase or sale of:

	●	debt or equity securities issued by us or securities of third parties, a basket of such securities, an index or indices or such securities;

	●	currencies;

	●	commodities; or

	●	any combination of the above as specified in the applicable prospectus supplement.

Each purchase contract will entitle the holder thereof to purchase or sell, and obligate us to sell or purchase, on specified dates, such securities, currencies, or commodities at a specified purchase price, which may be based on a formula, all as set forth in the applicable prospectus supplement. We may, however, satisfy our obligations, if any, with respect to any purchase contract by delivering the cash value of such purchase contract or the cash value of the property otherwise deliverable or, in the case of purchase contracts on underlying currencies, by delivering the underlying currencies, as set forth in the applicable prospectus supplement. The applicable prospectus supplement will also specify the methods by which the holders may purchase or sell such securities, currencies, or commodities and any acceleration, cancellation, or termination provisions or other provisions relating to the settlement of a purchase contract.

The purchase contracts may require us to make periodic payments to the holders thereof or vice versa, which payments may be deferred to the extent set forth in the applicable prospectus supplement, and those payments may be unsecured or prefunded on some basis. The purchase contracts may require the holders thereof to secure their obligations in a specified manner to be described in the applicable prospectus supplement. Alternatively, purchase contracts may require holders to satisfy their obligations thereunder when the purchase contracts are issued. Our obligation to settle such pre-paid purchase contracts on the relevant settlement date may constitute indebtedness. Accordingly, pre-paid purchase contracts will be issued under the applicable indenture.

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DESCRIPTION OF UNITS

The following description, together with the additional information we include in any applicable prospectus supplement, 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 future units we may offer, we will describe the particular terms of any units that we may offer in more detail in the applicable prospectus supplement. The terms of any units we offer under a prospectus supplement may differ from the terms we describe below.

We may issue units comprised of one or more of the other classes of securities described in this prospectus 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 included security. The units may be issued under unit agreements to be entered into between us and a unit agent, as detailed in the prospectus supplement relating to the units being offered. The prospectus supplement will describe:

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

	●	a description of the terms of any unit agreement governing the units;

	●	a description of the provisions for the payment, settlement, transfer, or exchange of the units;

	●	a discussion of material federal income tax considerations, if applicable; and

	●	whether the units if issued as a separate security will be issued in fully registered or global form.

The descriptions of the units in this prospectus and in any prospectus supplement are summaries of the material provisions of the applicable unit agreements. These descriptions do not restate those unit agreements in their entirety and may not contain all the information that you may find useful. We urge you to read the applicable unit agreements because they, and not the summaries, define your rights as holders of the units. For more information, please review the forms of the relevant unit agreements, which will be filed with the SEC promptly after the offering of units and will be available as described in the section titled “Where You Can Find Additional Information.”

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

Anti-Takeover Effects of Provisions of Our Charter Documents and Delaware Law

Delaware Anti-Takeover Law

We are subject to Section 203 of the DGCL (“Section 203”). Section 203 generally prohibits a public Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:

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

	●	the interested stockholder owned at least 85% of the voting stock of the corporation outstanding upon consummation of the transaction, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

	●	at or subsequent to the consummation of the transaction, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock which is not owned by the interested stockholder.

Section 203 defines a business combination to include:

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

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

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

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

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

In general, Section 203 defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.

Charter and Bylaws

Provisions of our Charter and Bylaws may delay or discourage transactions involving an actual or potential change-in-control or change in our management, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. Therefore, these provisions could adversely affect the price of our common stock. Among other things, our Charter and/or Bylaws:

●

permit our board of directors to issue up to 5,000,000 shares of preferred stock, with any rights, preferences and privileges as they may designate (including the right to approve an acquisition or other change in control);

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	●	provide that the authorized number of directors may be changed only by resolution adopted by a majority of the board of directors;

	●	provide that all vacancies, including newly created directorships, may, except as otherwise required by law or subject to the rights of holders of preferred stock as designated from time to time, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;

	●	require that any action to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders or by action taken by written consent;

	●	provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide notice in writing in a timely manner and also specify requirements as to the form and content of a stockholder’s notice; and

	●	provide that special meetings of our stockholders may be called only by the chairman of the board of directors, the President or by our board of directors pursuant to a resolution adopted by a majority of the total number of authorized directors (whether or not there exist any vacancies).

	●	provide that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall, to the fullest extent permitted by law, shall be the sole and exclusive forum for (1) any derivative action or proceeding brought on behalf of the Company, (2) any action asserting a claim of breach of a fiduciary duty owed by any current or former director, officer, employee or stockholder of the Company to the Company or the Company’s stockholders, (3) any action asserting a claim arising pursuant to any provision of the DGCL, the Charter or the Bylaws or as to which the DGCL confers jurisdiction on the Court of Chancery of the State of Delaware, or (4) any action asserting a claim governed by the internal affairs doctrine. Any person or entity purchasing or otherwise acquiring or holding any interest in shares of capital stock of the Company shall be deemed to have notice of and consented to the provisions of such provision. Because the applicability of the exclusive forum provision is limited to the extent permitted by applicable law, we do not intend that the exclusive forum provision would apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. We also acknowledge that Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder and that there is uncertainty as to whether a court would enforce an exclusive forum provision for actions arising under the Securities Act.

Limitation of Liability and Indemnification

Section 145 of the DGCL authorizes a court to award, or a corporation’s board of directors to grant, indemnity to directors and officers in terms sufficiently broad to permit such indemnification under certain circumstances for liabilities, including reimbursement for expenses incurred, arising under the Securities Act.

Our Charter and Bylaws provide that we will indemnify our directors and officers, and may indemnify our employees and other agents, to the fullest extent permitted by the DGCL. However, Delaware law prohibits our certificate of incorporation from limiting the liability of our directors for the following:

	●	any breach of the director’s duty of loyalty to us or to our stockholders;

	●	acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

	●	unlawful payment of dividends or unlawful stock repurchases or redemptions; and

	●	any transaction from which the director derived an improper personal benefit.

We have entered into agreements to indemnify each of our directors and officers. These agreements provide for the indemnification of such persons for all reasonable expenses and liabilities incurred in connection with any action or proceeding brought against them by reason of the fact that they are or were serving in such capacity.

We maintain insurance policies that indemnify our directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any director or officer in the director’s or officer’s capacity as such. We have obtained director and officer liability insurance to cover liabilities our directors and officers may incur in connection with their services to us.

The foregoing discussion of our Charter, Bylaws, indemnification agreements, and Delaware law is not intended to be exhaustive and is qualified in its entirety by such Charter, Bylaws, indemnification agreements, or law.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to our directors, officers and controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.

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LEGAL OWNERSHIP OF SECURITIES

We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee, depository or warrant agent maintain for this purpose as the “holders” of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as “indirect holders” of those securities.

As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary’s book-entry system. These participating institutions, which are referred to as participants, in turn hold beneficial interests in the securities on behalf of themselves or their customers.

Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its participants. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker, or other financial institution that participates in the depositary’s book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not holders, of the securities.

Street Name Holders

We may terminate a global security or issue securities in non-global form. In these cases, investors may choose to hold their securities in their own names or in “street name.” Securities held by an investor in street name would be registered in the name of a bank, broker, or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account the investor maintains at that institution.

For securities held in street name, we will recognize only the intermediary banks, brokers, and other financial institutions in whose names the securities are registered as the holders of those securities, and we will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.

Legal Holders

Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

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For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with depositary participants or customers or by law, to pass it along to the indirect holders but does not do so.

Special Considerations for Indirect Holders

If you hold securities through a bank, broker or other financial institution, either in book-entry form or in street name, you should check with your own institution to find out:

	●	how it handles securities payments and notices;

	●	whether it imposes fees or charges;

	●	how it would handle a request for the holders’ consent, if ever required;

	●	whether and how you can instruct it to send you securities registered in your own name so you can be a holder, if that is permitted in the future;

	●	how it would exercise rights under the securities if there were a default or other event triggering the need for holders to act to protect their interests; and

	●	if the securities are in book-entry form, how the depositary’s rules and procedures will affect these matters.

Global Securities

A global security is a security that represents one or any other number of individual securities held by a depositary. Generally, all securities represented by the same global securities will have the same terms.

Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, the Depository Trust Company, or DTC, will be the depositary for all securities issued in book-entry form.

A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under “— Special Situations When a Global Security Will Be Terminated.” As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a holder of the security, but only an indirect holder of a beneficial interest in the global security.

If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

Special Considerations for Global Securities

As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

If securities are issued only in the form of a global security, an investor should be aware of the following:

●

An investor cannot cause the securities to be registered in the investor’s and cannot obtain non-global certificates for the investor’s interest in the securities, except in the special situations we describe below.

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	●	An investor will be an indirect holder and must look to such investor’s own bank or broker for payments on the securities and protection of such investor’s legal rights relating to the securities, as we describe above.

	●	An investor may not be able to sell interests in the securities to some insurance companies and to other institutions that are required by law to own their securities in non-book-entry form.

	●	An investor may not be able to pledge such investor’s interest in a global security in circumstances where certificates representing the securities must be delivered to the lender or other beneficiary of the pledge in order for the pledge to be effective.

	●	The depositary’s policies, which may change from time to time, will govern payments, transfers, exchanges, and other matters relating to an investor’s interest in a global security. We and any applicable trustee have no responsibility for any aspect of the depositary’s actions or for its records of ownership interests in a global security. We and the trustee also do not supervise the depositary in any way.

	●	The depositary may, and we understand that DTC will, require that those who purchase and sell interests in a global security within its book-entry system use immediately available funds, and your broker or bank may require you to do so as well.

	●	Financial institutions that participate in the depositary’s book-entry system, and through which an investor holds its interest in a global security, may also have their own policies affecting payments, notices and other matters relating to the securities. There may be more than one financial intermediary in the chain of ownership for an investor. We do not monitor and are not responsible for the actions of any of those intermediaries.

Special Situations When a Global Security Will Be Terminated

In a few special situations described below, the global security will terminate, and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.

The global security will terminate when the following special situations occur:

	●	if the depositary notifies us that it is unwilling, unable or no longer qualified to continue as depositary for that global security and we do not appoint another institution to act as depositary within 90 days;

	●	if we notify any applicable trustee that we wish to terminate that global security; or

	●	if an event of default has occurred with regard to securities represented by that global security and has not been cured or waived.

The applicable prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

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PLAN OF DISTRIBUTION

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

	●	to or through underwriters or dealers;

	●	directly to one or more purchasers; or

	●	through agents.

We may distribute the securities:

	●	from time to time in one or more transactions at a fixed price or prices, which may be changed from time to time;

	●	in “at the market” offerings, as defined in Rule 415 under the Securities Act, at negotiated prices, at prices prevailing at the time of sale or at prices related to such prevailing market prices, including sales made directly on a national securities exchange or sales made through a market maker other than on an exchange or other similar offerings through sales agents; or

	●	at negotiated prices.

Each time we offer and sell securities covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms of the offering, including:

	●	the name or names of any underwriters, dealers, or agents;

	●	the amounts of securities underwritten or purchased by each of them;

	●	the purchase price of securities and the proceeds we will receive from the sale;

	●	any option under which underwriters may purchase additional securities from us;

	●	any underwriting discounts or commissions or agency fees and other items constituting underwriters’ or agents’ compensation;

	●	the public offering price of the securities;

	●	any discounts, commissions or concessions allowed or reallowed or paid to dealers; and

	●	any securities exchange or market on which the securities may be listed.

Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time. We may determine the price or other terms of the securities offered under this prospectus by use of an electronic auction. We will describe how any auction will determine the price or any other terms, how potential investors may participate in the auction and the nature of the obligations of the underwriter, dealer, or agent in the applicable prospectus supplement.

Underwriters or dealers may offer and sell the offered securities 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. If underwriters or dealers are used in the sale of any securities, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions described above. The securities may be either offered to the public through underwriting syndicates represented by managing underwriters, or directly by underwriters or dealers. Generally, the underwriters’ or dealers’ obligations to purchase the securities will be subject to certain conditions precedent. The underwriters or dealers will be obligated to purchase all of the securities if they purchase any of the securities, unless otherwise specified in the prospectus supplement. We may use underwriters with whom we have a material relationship. We will describe the nature of any such relationship in the prospectus supplement, naming the underwriter.

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

All securities we may offer, other than common stock, will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities.

Any underwriter may engage in over-allotment, stabilizing transactions, short covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Over-allotment involves sales in excess of the offering size, which create a short position. This short sales position may involve either “covered” short sales or “naked” short sales. Covered short sales are short sales made in an amount not greater than the underwriters’ over-allotment option to purchase additional securities in the relevant offering. The underwriters may close out any covered short position either by exercising their over-allotment option or by purchasing securities in the open market. To determine how they will close the covered short position, the underwriters will consider, among other things, the price of securities available for purchase in the open market, as compared to the price at which they may purchase securities through the over-allotment option. Naked short sales are short sales in excess of the over-allotment option. The underwriters must close out any naked short position by purchasing securities in the open market. A naked short position is more likely to be created if the underwriters are concerned that, in the open market after pricing, there may be downward pressure on the price of the securities that could adversely affect investors who purchase securities in the offering. Stabilizing transactions permit bids to purchase the underlying security for the purpose of fixing the price of the security so long as the stabilizing bids do not exceed a specified maximum. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a covering transaction to cover short positions.

Any underwriters who are qualified market makers on The Nasdaq Capital Market may engage in passive market making transactions in our common stock, preferred stock, warrants and debt securities, as applicable on The Nasdaq Capital Market in accordance with Rule 103 of Regulation M, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded.

Similar to other purchase transactions, an underwriter’s purchase to cover the syndicate short sales or to stabilize the market price of our securities may have the effect of raising or maintaining the market price of our securities or preventing or mitigating a decline in the market price of our securities. As a result, the price of our securities may be higher than the price that might otherwise exist in the open market. The imposition of a penalty bid might also have an effect on the price of the securities if it discourages resales of the securities.

Neither we nor any underwriter makes any representation or prediction as to the effect that the transactions described above may have on the price of the securities. If such transactions are commenced, they may be discontinued without notice at any time.

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LEGAL MATTERS

The validity of the securities being offered by this prospectus will be passed upon for us by Thompson Hine LLP, New York, New York.

EXPERTS

The 2025 and 2024 audited annual consolidated financial statements of Vaxart, Inc. as of and for each of the years in the two-year period ended December 31, 2025, incorporated by reference in this prospectus and elsewhere in the registration statement, have been incorporated by reference in reliance upon the report of WithumSmith+Brown, PC, independent registered public accounting firm, upon the authority of said firm as experts in accounting and auditing.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

This prospectus is part of a shelf registration statement that we have filed with the SEC. This prospectus does not contain all of the information in the registration statement and its exhibits. For further information with respect to us and the securities offered by this prospectus, we refer you to the registration statement and its exhibits. Statements contained in this prospectus as to the contents of any contract or any other document referred to are not necessarily complete, and in each instance, we refer you to the copy of the contract or other document filed as an exhibit to the registration statement. Each of these statements is qualified in all respects by this reference. The SEC maintains an internet website that contains reports, proxy statements, and other information about registrants, like us, that file electronically with the SEC. The address of that website is www.sec.gov. The information contained in, or that can be accessed through, the SEC’s website is not incorporated by reference in, and is not part of, this prospectus or any prospectus supplement.

We are subject to the information and periodic reporting requirements of the Exchange Act, and we file periodic reports, proxy statements and other information with the SEC. We maintain a website at https://www.vaxart.com. You may access our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act with the SEC free of charge at our website as soon as reasonably practicable after such material is electronically filed with, or furnished to, the SEC. The information contained in, or that can be accessed through, our website is not incorporated by reference in, and is not part of, this prospectus or any prospectus supplement.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus to the extent that a statement contained in this prospectus or free writing prospectus provided to you in connection with this offering, or in any other document we subsequently file with the SEC that also is incorporated by reference in this prospectus, modifies or supersedes the original statement.

The following documents filed with the SEC are hereby incorporated by reference in this prospectus:

	●	our Annual Report on Form 10 -K for the year ended December 31, 2025, filed with the SEC on March 13, 2026; and

	●	the description of our common stock contained in our Registration Statement on Form 10, filed with the SEC on May 4, 1970, as amended by our Current Report on Form 8-K (File No. 000-04829) filed with the SEC on August 15, 2003.

All reports and other documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this prospectus and prior to the termination of this offering shall be deemed to be incorporated by reference in this prospectus and to be part hereof from the date of filing of such reports and other documents.

We will furnish without charge to you, on written or oral request, a copy of any or all of the documents incorporated by reference, including exhibits to these documents. You should direct any requests for documents by writing us at 310 Utah Avenue, Suite 150, South San Francisco, California, 94080 or by telephoning us at (650) 550-3500.

Notwithstanding the statements in the preceding paragraphs, no document, report, or exhibit (or portion of any of the foregoing) or any other information that we have “furnished” or may in the future “furnish” to the SEC pursuant to the Exchange Act shall be incorporated by reference into this prospectus or any prospectus supplement.

In accordance with Rule 412 of the Securities Act, any statement contained in a document incorporated by reference herein shall be deemed modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement.

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Common Stock

Preferred Stock

Debt Securities

Warrants

Purchase Contracts

Units

$300,000,000

PROSPECTUS

__________, 2026

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THE INFORMATION IN THIS PROSPECTUS SUPPLEMENT 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 SUPPLEMENT IS NOT AN OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY JURISDICTION WHERE THE OFFER OR SALE IS NOT PERMITTED.

SUBJECT TO COMPLETION, DATED APRIL 15, 2026

PROSPECTUS SUPPLEMENT

(To Prospectus, dated __________, 2026)

Up to $49,772,479 of Shares of

Common Stock

We have entered into an At the Market Offering Agreement, dated March 21, 2025 (the “Sales Agreement”) with Citizens JMP Securities, LLC and B. Riley Securities, Inc. (the “Sales Agents”) relating to shares of our common stock, par value $0.0001 per share, offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $49,772,479 from time to time through the Sales Agents.

Upon our delivery of a placement notice and subject to the terms and conditions of the Sales Agreement, the Sales Agents may sell the common stock by methods deemed to be an “at the market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended (the “Securities Act”), including sales made directly on The Nasdaq Capital Market (“Nasdaq”), on any other existing trading market for the common stock or to or through a market maker other than on an exchange. In addition, with our prior written approval, the Sales Agents may also sell the common stock by any other method permitted by law, including in privately negotiated transactions. If we and the Sales Agents agree on any method of distribution other than sales of shares of our common stock on or through The Nasdaq Capital Market or another existing trading market in the United States at market prices, we will file a further prospectus supplement providing all information about such offering as required by Rule 424(b) under the Securities Act. The Sales Agents are not required to sell any specific number or dollar amount of our common stock, but will use its commercially reasonable efforts, as our sales agent and subject to the terms of the sales agreement, to sell the shares of common stock offered, as instructed by us and applicable state and federal laws, rules and regulations and the rules of the Nasdaq. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

Each of the Sales Agents will be entitled to compensation under the terms of the sales agreement at a fixed commission rate, in the aggregate, of up to 3% of the gross sales price per share sold, in addition to reimbursement of certain expenses. See “Plan of Distribution” for information relating to certain expenses of the sales agent to be reimbursed by us.

In connection with the sale of common stock on our behalf, each of the Sales Agents may be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation to each of the Sales Agents will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to each of the Sales Agents with respect to certain liabilities, including liabilities under the Securities Act.

The net proceeds we receive from any sales under this prospectus supplement will be the gross proceeds from such sales less the commissions and any other costs we may incur in offering the common stock. See “Use of Proceeds” and “Plan of Distribution” for additional information.

Our common stock is traded on the OTCQX® Best Market under the symbol “VXRT.” On April 10, 2026, the reported closing price of the common stock was $0.63 per share.

Investing in our securities involves risk. See “Risk Factors” beginning on page S-4 of this prospectus supplement, on page S-4 of the accompanying base prospectus and in our filings with the Securities Exchange Commission (the “SEC”), that are incorporated by reference herein and therein to read about factors you should consider before investing in our securities.

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

Citizens Capital Markets B. Riley Securities

The date of this prospectus supplement is __________, 2026.

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TABLE OF CONTENTS

	Page

ABOUT THIS PROSPECTUS SUPPLEMENT	S-1
PROSPECTUS SUPPLEMENT SUMMARY	S-2
THE OFFERING	S-3
RISK FACTORS	S-4
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS	S-9
USE OF PROCEEDS	S-10
DIVIDEND POLICY	S-10
DILUTION	S-11
PLAN OF DISTRIBUTION	S-12
LEGAL MATTERS	S-13
EXPERTS	S-13
WHERE YOU CAN FIND ADDITIONAL INFORMATION	S-13
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE	S-13

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ABOUT THIS PROSPECTUS SUPPLEMENT

We provide information to you about this offering of securities in two separate documents that are bound together: (1) this prospectus supplement, which describes the specific details regarding this offering; and (2) the accompanying base prospectus, which provides general information, some of which may not apply to this offering. If information in this prospectus supplement is inconsistent with the accompanying base prospectus, you should rely on this prospectus supplement. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date - for example, a document incorporated by reference in this prospectus supplement - the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations, and prospects may have changed since the earlier dates.

We have not, and the Sales Agents have not, authorized anyone to provide you with any information that is in addition to or different from that contained or incorporated by reference in this prospectus supplement, the accompanying base prospectus, or in any free writing prospectus we have prepared. We and the Sales Agents take no responsibility for, and provide no assurance as to the reliability of, any other information that others may give you. We and the Sales Agents are not making an offer to sell or soliciting an offer to buy our securities in any jurisdiction where an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information appearing in this prospectus supplement, the accompanying base prospectus, the documents incorporated by reference herein and therein, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations, and prospects may have changed since those dates. You should read this prospectus supplement, the accompanying base prospectus, the documents incorporated by reference into this prospectus supplement and the base prospectus, and any free writing prospectus that we may authorize for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents to which we have referred you in the section of this prospectus supplement titled “Where You Can Find Additional Information.”

We and the Sales Agents 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 base 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 base 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 base prospectus outside the United States. This prospectus supplement and the accompanying base prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying base prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

When we refer to “Vaxart,” “we,” “our,” “us,” and the “Company” in this prospectus supplement, we mean Vaxart, Inc., and our consolidated subsidiaries unless otherwise specified.

Vaxart® and the Vaxart logo are some of our trademarks used in this prospectus supplement. This prospectus supplement also includes trademarks, tradenames, and service marks that are the property of other organizations. Solely for convenience, our trademarks and tradenames referred to in this prospectus supplement appear without the ® and ™ 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 the right of the applicable licensor to these trademarks and tradenames.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary provides a general overview of selected information and does not contain all of the information you should consider before buying our securities. Therefore, you should read the entire prospectus supplement, accompanying base prospectus, and any free writing prospectus that we have authorized for use in connection with this offering carefully, including the information incorporated by reference, before deciding to invest in our securities. Investors should carefully consider the information set forth under “Risk Factors” beginning on page S-4 of this prospectus supplement and incorporated by reference to our most recent Annual Report on Form 10-K, as supplemented by any additional SEC filings.

Our Company

Corporate History and Reorganization

Our corporate headquarters and laboratory are located at 310 Utah Avenue, Suite 150, South San Francisco, California 94080, and our telephone number is (650) 550-3500. We maintain a website at https://www.vaxart.com, to which we regularly post copies of our press releases as well as additional information about us. The information contained on, or that can be accessed through, our website is not a part of this prospectus supplement or the accompanying base prospectus. We have included our website address in this prospectus supplement solely as an inactive textual reference.

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THE OFFERING

Common stock offered by us		Shares of our common stock having an aggregate offering price of up to $49,772,479 pursuant to the Sales Agreement.

Common stock currently outstanding		241,414,053 shares

Common stock to be outstanding immediately after this offering		Up to 320,417,987 shares, assuming sales at a sales price of $0.63 per share, which was the closing sale price on the OTCQX® Best Market on April 10, 2026. The actual number of shares of common stock outstanding following this offering will vary depending on several factors, including whether we elect to sell shares pursuant to this offering and the price at which the shares may be sold from time to time during this offering.

Manner of Offering		An “at-the-market” offering that may be made from time to time through or to the Sales Agents. See the section titled “Plan of Distribution.”

Use of proceeds		We currently intend to use the net proceeds from this offering primarily for general corporate purposes, including working capital, operating expenses and capital expenditures. See the section titled “Use of Proceeds.”

Risk factors		An investment in our securities involves a high degree of risk. You should read the section titled “Risk Factors,” in this prospectus supplement and in the documents incorporated by reference into this prospectus supplement for a discussion of factors to consider before deciding to purchase shares of our common stock.

The OTCQX® Best Market symbol		“VXRT”

The above discussion is based on 241,414,053 shares of our common stock outstanding as of April 10, 2026, but excludes:

	●	27,767,619 shares issuable upon the exercise of outstanding stock options at April 10, 2026, with a weighted-average exercise price of $1.62 per share;

	●	6,691,605 shares issuable upon the vesting of outstanding restricted stock units (“RSUs”) at April 10, 2026;

	●	6,088,856 shares reserved for future issuance under our 2019 Equity Incentive Plan as of April 10, 2026, which amount includes an increase of 15,000,000 shares approved by stockholders at the annual meeting of stockholders held on June 11, 2024;

	●	31,250 shares reserved for future issuance under our 2024 Inducement Award Plan as of April 10, 2026;

	●	10,914 shares issuable upon the exercise of outstanding warrants at April 10, 2026, with a weighted-average exercise price of $22.99 per share; and

	●	1,823,454 shares reserved for future issuance under our 2022 Employee Stock Purchase Plan (“ESPP”) at April 10, 2026, which amount includes an increase of 1,800,000 shares approved by stockholders at the annual meeting of stockholders held on June 11, 2024.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should consider carefully the risks described below and discussed under the section captioned “Risk Factors” contained in our Annual Report on Form 10-K for the year ended December 31, 2025, as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), each of which is incorporated by reference in this prospectus supplement in its entirety, together with other information in this prospectus supplement, the accompanying base prospectus, the information and documents incorporated by reference in this prospectus supplement and the base prospectus, and any free writing prospectus that we have authorized for use in connection with this offering before you make a decision to invest in our securities. If any of the risks described therein or below actually occur, our business, operating results, prospects, or financial condition could be materially and adversely affected. This could cause the trading price of our common stock to decline and you may lose all or part of your investment. The risks described below are not the only ones that we face. Additional risks not presently known to us or that we currently deem immaterial may also affect our business operations.

Risks Related to this Offering

Our recurring losses from operations and negative cash flows have raised substantial doubt regarding our ability to continue as a going concern. We will require substantial additional funding to finance our operations, and if we are unable to raise capital, we could be forced to delay, reduce the scope of or eliminate certain of our development programs, or explore other strategic options.

Our recurring losses from operations and negative cash flows raise substantial doubt about our ability to continue as a going concern. As of December 31, 2025, we had $63.8 million of cash, cash equivalents and investments. We believe these funds are sufficient to fund our operations into the second quarter of 2027. Our ability to continue as a going concern is dependent upon our ability to raise additional capital through outside sources. We plan to raise additional capital through the sale of convertible stock, additional equity, debt financings, government programs, or strategic alliances with third parties. Such financing and funding may not be available at all, or on terms that are favorable to us. Failure to raise additional capital could have a material adverse effect on our business, results of operations, financial condition and/or our ability to fund our scheduled obligations on a timely basis or at all. If we are unable to continue as a going concern, we may be forced to liquidate our assets and the values we receive for our assets in liquidation or dissolution could be significantly lower than the values reflected in our consolidated financial statements. Any such failure could cause the market price of our common stock to decrease and limit the volume of trading in our common stock.

We recently transferred the trading of our common stock from The Nasdaq Stock Market to the OTCQX® Best Market after our common stock was delisted from Nasdaq. Because our common stock is quoted on the OTCQX® Best Market, your ability to sell your shares in the secondary trading market may be limited.

Effective July 8, 2025, Nasdaq suspended trading in our common stock and subsequently informed the company on September 19, 2025 that the Company’s common stock will be delisted from The Nasdaq Capital Market. Our common stock is currently quoted on the OTCQX® Best Market under the ticker symbol “VXRT.”

As a result of the transfer of the our common stock from Nasdaq to the OTCQX® Best Market, we anticipate that our stockholders could experience negative consequences related to our securities, including but not limited to: limited availability of market quotations for our securities; a reduced level of trading activity in the secondary trading market for shares of our common stock; a limited amount of analyst coverage; and decreased ability to issue additional securities or obtain additional financing in the future.

Because our common stock is quoted on the OTCQX® Best Market, your ability to sell your shares in the secondary trading market may be limited. Since July 8, 2025, the OTCQX® Best Market is the only liquidity platform for our common stock. We cannot assure our stockholders that our common stock will continue to trade on this liquidity platform, whether broker-dealers will continue to provide public quotes of our common stock on this liquidity platform, whether the trading volume of our common stock will be sufficient to provide for respective efficient liquidity platforms or whether quotes for our common stock will continue on this liquidity platform in the future, which could result in significantly lower trading volumes and reduced liquidity for investors seeking to buy or sell our common stock. As a result, prices for shares of our common stock may be lower than might otherwise prevail if our common stock was listed on a national securities exchange.

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The National Securities Markets Improvement Act of 1996, which is a federal statute, prevents or preempts the states from regulating the sale of certain securities, which are referred to as “covered securities.” Shares of our common stock were considered to be covered securities because they were listed on The Nasdaq Capital Market. Because our common stock is no longer listed on The Nasdaq Capital Market, our common stock is not deemed covered securities and we are subject to regulation in each state in which we offer our securities.

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:

	●	our ability to develop product candidates and conduct clinical trials that demonstrate our product candidates are safe and effective;

	●	our ability to negotiate and receive royalty payments on the sales of our product candidates including Inavir;

	●	our ability to obtain regulatory approvals for our product candidates, and delays or failures to obtain such approvals;

	●	failure of any of our product candidates to demonstrate safety and efficacy, receive regulatory approval and achieve commercial success;

	●	failure to maintain our existing third-party license, manufacturing and supply agreements;

	●	our failure, or that of our licensors, to prosecute, maintain, or enforce our intellectual property rights;

	●	changes in laws or regulations applicable to our product candidates;

	●	any inability to obtain adequate supply of product candidates or the inability to do so at acceptable prices;

	●	adverse regulatory authority decisions;

	●	introduction of new or competing products by our competitors;

	●	failure to meet or exceed financial and development projections that we may provide to the public;

	●	the perception of the pharmaceutical industry by the public, legislatures, regulators and the investment community;

	●	announcements of significant acquisitions, strategic partnerships, joint ventures, or capital commitments by us or our competitors;

	●	disputes or other developments relating to proprietary rights, including patents, litigation matters, and our ability to obtain intellectual property protection for our technologies;

	●	additions or departures of key personnel;

	●	significant lawsuits, including intellectual property or stockholder litigation;

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	●	if securities or industry analysts do not publish research or reports about us, or if they issue adverse or misleading opinions regarding our business and stock;

	●	changes in the market valuations of similar companies;

	●	general market or macroeconomic conditions;

	●	sales of our common stock by our existing stockholders in the future;

	●	trading volume of our common stock;

	●	adverse publicity relating to our markets generally, including with respect to other products and potential products in such markets;

	●	changes in the structure of health care payment systems; and

	●	period-to-period fluctuations in our financial results.

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. These broad market and industry factors may seriously harm the market price of our common stock, regardless of our operating performance.

We will require additional capital funding, the receipt of which may impair the value of our common stock.

Our future capital requirements depend on many factors, including our research, development, sales and marketing activities. We will need to raise additional capital through public or private equity or debt offerings or through arrangements with strategic partners or other sources in order to continue to develop our drug candidates. There can be no assurance that additional capital will be available when needed or on terms satisfactory to us, if at all. To the extent we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution and the new equity securities may have greater rights, preferences or privileges than our existing common stock.

You will experience immediate and substantial dilution in the net tangible book value per share of the common stock you purchase.

The offering price per share in this offering may exceed the net tangible book value per share of our common stock outstanding prior to this offering. Assuming that an aggregate of 79,003,934 shares of our common stock are sold at the assumed offering price of $0.63 per share (the last reported sale price of our common stock on the OTCQX® Best Market on April 10, 2026) and after deducting commissions and estimated aggregate offering expenses payable by us, you will experience immediate dilution of $0.23 per share, representing the difference between our as adjusted net tangible book value per share as of December 31, 2025 after giving effect to this offering and the assumed offering price. 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.

In addition, 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. In the event that other outstanding options or warrants are exercised or settled, or if we make additional issuances of common stock or other convertible or exchangeable securities, you could experience additional dilution. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders, including investors who purchase shares of common stock in this offering. The price per share at which we sell additional shares of our common stock or securities convertible into common stock in future transactions, may be higher or lower than the price per share in this offering. Additionally, the exercise of warrants, exercise of outstanding stock options, conversion of outstanding preferred stock, and vesting of other stock awards may result in further dilution of your investment.

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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.

In addition, we have a significant number of warrants and options outstanding. To the extent that outstanding options or warrants have been or may be exercised or converted or other shares of common stock are issued, you may experience further dilution. Further, 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, which may lead to further dilution.

Issuances and resales of our common stock in the public market by our stockholders during this offering may cause the market price of our common stock to fall.

We may issue common stock from time to time in connection with this offering. The issuance from time to time of these new shares of our common stock, or our ability to issue new shares of common stock in this offering, could result in resales of our common stock by our current stockholders concerned about the potential dilution of their holdings. In turn, these resales could have the effect of depressing the market price for our common stock.

We have broad discretion in the use of the net proceeds from this offering and may invest or spend the proceeds in ways with which you do not agree and in ways that may not yield a return on your investment.

Although we currently intend to use the net proceeds from this offering in the manner described in the section titled “Use of Proceeds” in this prospectus supplement, 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. You will not have the opportunity to influence our decisions on how to use the net proceeds from this offering. The failure by our management to apply these funds effectively could result in financial losses that could harm our business, cause the price of our common stock to decline, and delay the development of our product candidates. Pending their use, we may invest the net proceeds from this offering in a manner that does not produce income or that loses value.

Because we do not intend to declare cash dividends on our shares of common stock in the foreseeable future, stockholders must rely on appreciation of the value of our common stock for any return on their investment.

We have never declared or paid cash dividends on our common stock. We currently anticipate that we will retain future earnings for the development, operation and expansion of our business and do not anticipate declaring or paying any cash dividends in the foreseeable future. In addition, the terms of any existing or future debt agreements may preclude us from paying dividends. As a result, we expect that only appreciation of the price of our common stock, if any, will provide a return to investors in this offering for the foreseeable future.

Investing in our common stock may involve a high degree of risk.

The investments that we make in accordance with our investment objectives may result in a high amount of risk, resulting in a complete loss of principal, when compared to alternative investment options. Our investments may be highly speculative and aggressive, and therefore an investment in our common stock may not be suitable for someone with lower risk tolerance.

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It is not possible to predict the aggregate proceeds resulting from sales made under the sales agreement.

Subject to certain limitations in the sales agreement and compliance with applicable law, we have the discretion to deliver a placement notice to the Sales Agents at any time throughout the term of the Sales Agreement. The number of shares that are sold through each of the Sales Agents after delivering a placement notice will fluctuate based on a number of factors, including the market price of our common stock during the sales period, the limits we set with the Sales Agents in any applicable placement notice, and the demand for our common stock during the sales period. Because the price per share of each share sold will fluctuate during the sales period, it is not currently possible to predict the aggregate proceeds to be raised in connection with those sales.

The common stock offered hereby will be sold in “at the market offerings,” and investors who buy shares at different times will likely pay different prices.

Investors who purchase shares in this offering at different times will likely pay different prices, and so may experience different levels of dilution and different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and number of shares sold in this offering. In addition, subject to the final determination by our board of directors, there is no minimum or maximum sales price for shares to be sold in this offering. Investors may experience a decline in the value of the shares they purchase in this offering as a result of sales made at prices lower than the prices they paid.

The actual number of shares we will issue under the sales agreement with each of the Sales Agents, at any one time or in total, is uncertain.

Subject to certain limitations in the sales agreement with the Sales Agents and compliance with applicable law, we have the discretion to deliver placement notices to the Sales Agents at any time throughout the term of the sales agreement. The number of shares that are sold by each of the Sales Agents after delivering a placement notice will fluctuate based on the market price of the common stock during the sales period and limits we set with the Sales Agents.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying base prospectus, the documents incorporated by reference, and any free writing prospectus that we have authorized for use in connection with this offering contain forward-looking statements concerning our business, operations, and financial performance and condition, as well as our plans, objectives, and expectations for our business, operations, and financial performance and condition. Any statements contained herein that are not statements of historical facts may be deemed to be forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “aim,” “anticipate,” “assume,” “believe,” “contemplate,” “continue,” “could,” “due,” “estimate,” “expect,” “goal,” “intend,” “may,” “objective,” “plan,” “predict,” “potential,” “positioned,” “seek,” “should,” “target,” “will,” “would,” and other similar expressions that are predictions or indicate future events and future trends, or the negative of these terms or other comparable terminology. These forward-looking statements include, but are not limited to, statements about:

	●	our ability to develop and commercialize our product candidates and clinical results and trial data;

	●	our ability to negotiate and receive royalty payments on the sales of our product candidates including Inavir;

	●	our ability to obtain the various synergies envisioned in the Exclusive License and Collaboration Agreement with Dynavax Technologies Corporation;

	●	estimates of selected financial results for future time periods;

	●	our ability to obtain, maintain, and enforce necessary patent and other intellectual property protection;

	●	potential partnership opportunities;

	●	expectations regarding the future contributions of our management team;

	●	the ability of our management team to build out the Company and drive sustainable growth and value creation;

	●	our ability to manufacture vaccine tablets;

	●	expectations regarding clinical results and trial data;

	●	expectations regarding the effectiveness, safety, or convenience of our norovirus vaccine candidate;

	●	expectations regarding the effectiveness, safety, or convenience of any other vaccine candidate;

	●	the anticipated use of proceeds from this offering; and

	●	our expectations with respect to the important advantages we believe our oral vaccine platform can offer over injectable alternatives.

These forward-looking statements are based on management’s current expectations, estimates, forecasts, and projections about our business and the industry in which we operate and involve known and unknown risks, uncertainties, and other factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in this prospectus supplement may turn out to be inaccurate. Factors that may cause actual results to differ materially from current expectations include, among other things, those listed under “Risk Factors” and elsewhere in this prospectus supplement, the base prospectus, or the documents incorporated by reference. Potential investors are urged to consider these factors carefully in evaluating the forward-looking statements. These forward-looking statements speak only as of the date hereof and as of the dates indicated in these statements. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. Given these risks and uncertainties, you are cautioned not to rely on such forward-looking statements as predictions of future events. You should, however, review the factors and risks we describe in the reports we will file from time to time with the SEC after the date of this prospectus supplement. See the section titled “Where You Can Find Additional Information” of this prospectus supplement.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus supplement, and while we believe such information forms a reasonable basis for such statements, and our management is responsible for the accuracy of such information, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

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USE OF PROCEEDS

The proceeds from this offering may vary if we choose to raise less than, or are unable to raise up to, the maximum $49,772,479 in gross offering proceeds permitted by this prospectus supplement. The number of shares that we offer and the offering price per share also may vary. There can be no assurance that we will be able to sell any shares or fully utilize the Sales Agreement as a source of financing. Because there is no minimum offering amount required as a condition to close this offering, the net proceeds to us, if any, are not determinable at this time.

We will retain broad discretion over the use of the net proceeds from the sale of the securities offered hereby. We currently intend to use the net proceeds from this offering primarily for general corporate purposes, including working capital, operating expenses and capital expenditures.

The amounts and timing of our use of the net proceeds from this offering will depend on a number of factors, such as the timing, scope, progress, and results of our development efforts and the timing and progress of any collaboration efforts. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses of the proceeds from the sale of securities under this prospectus supplement. Accordingly, we will retain broad discretion over the use of such proceeds. Pending the use of the net proceeds from the sale of securities under this prospectus supplement as described above, we intend to invest the net proceeds in investment-grade, interest-bearing instruments.

DIVIDEND POLICY

We have never declared or paid dividends on shares of our common stock. We intend to retain future earnings, if any, to support the development of our vaccine candidates and our business and therefore do not anticipate paying cash dividends for the foreseeable future. Payment of future dividends, if any, will be at the discretion of our board of directors after taking into account various factors, including current financial condition, operating results, and current and anticipated cash needs.

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DILUTION

If you invest in our common stock in this offering, your interest will be diluted immediately to the extent of the difference between the offering price per share you will pay in this offering and the as adjusted net tangible book value per share of our common stock after this offering.

Our historical net tangible book value as of December 31, 2025 was approximately $80.5 million, or $0.33 per share of common stock. Historical net tangible book value per share represents the amount of our total tangible assets less total liabilities, divided by the number of shares of our common stock outstanding on December 31, 2025.

After giving effect to our issuance and sale of 79,003,934 shares of common stock in this offering at an offering price of $0.63 per share (which was the last reported sale price on April 10, 2026), and after deducting estimated offering expenses and after deducting estimated sales agent discounts payable by us, our as adjusted net tangible book value as of December 31, 2025 would have been $128.7 million, or $0.40 per share. This represents an immediate increase in net tangible book value per share of $0.07 to existing stockholders and immediate dilution of $0.23 in net tangible book value per share to new investors purchasing securities in this offering. Dilution per share to new investors is determined by subtracting as adjusted net tangible book value per share after this offering from the offering price per share paid by new investors. The following table illustrates this per share dilution to the new investors purchasing securities in this offering:

Offering price per share			$	0.63
Net tangible book value per share as of December 31, 2025	$	0.33
Increase in net tangible book value per share attributable to sale of shares of common stock in this offering		0.07

As adjusted net tangible book value per share after this offering				0.40

Dilution per share to new investors			$	0.23

The above discussion is based on 241,414,053 shares of our common stock outstanding as of April 10, 2026, but excludes:

	●	27,767,619 shares issuable upon the exercise of outstanding stock options at April 10, 2026, with a weighted-average exercise price of $1.62 per share;

	●	6,691,605 shares issuable upon the vesting of outstanding restricted stock units (“RSUs”) at April 10, 2026;

	●	6,088,856 shares reserved for future issuance under our 2019 Equity Incentive Plan as of April 10, 2026, which amount includes an increase of 15,000,000 shares approved by stockholders at the annual meeting of stockholders held on June 11, 2024;

	●	31,250 shares reserved for future issuance under our 2024 Inducement Award Plan as of April 10, 2026;

	●	10,914 shares issuable upon the exercise of outstanding warrants at April 10, 2026, with a weighted-average exercise price of $22.99 per share; and

	●	1,823,454 shares reserved for future issuance under our 2022 Employee Stock Purchase Plan (“ESPP”) at April 10, 2026, which amount includes an increase of 1,800,000 shares approved by stockholders at the annual meeting of stockholders held on June 11, 2024.

To the extent that options outstanding as of December 31, 2025 have been or may be exercised or other shares are 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.

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PLAN OF DISTRIBUTION

We have entered into a Sales Agreement with Citizens JMP Securities, LLC (“Citizens”) and B. Riley Securities, Inc. (“B. Riley Securities” and, together with Citizens, the “Sales Agents”), pursuant to which we may issue and sell shares of our common stock having an aggregate offering price of up to $49,772,479 from time to time through or to the Sales Agents as sales agents or principals. The Sales Agents may sell the common stock by any method that is deemed to be an “at the market offering” as defined in Rule 415 promulgated under the Securities Act, including (i) in privately negotiated transactions with the consent of the Company; (ii) as block transactions; or (iii) by any other method permitted by law deemed to be an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act, including sales made directly on or through The Nasdaq Capital Market or any other existing trading market in the United States for our common stock. If we and the Sales Agents agree on any method of distribution other than sales of shares of our common stock on or through The Nasdaq Capital Market or another existing trading market in the United States at market prices, we will file a further prospectus supplement providing all information about such offering as required by Rule 424(b) under the Securities Act.

Each time we wish to issue and sell common stock under the Sales Agreement, we will notify each of the Sales Agents of the number or dollar value of shares to be issued, the dates on which such sales are anticipated to be made, any limitation on the number of shares that may be sold in one day, any minimum price below which sales may not be made, and other sales parameters as we deem appropriate. Once we have so instructed each of the Sales Agents, unless each of the Sales Agents decline to accept the terms of such notice, they have agreed to use their commercially reasonable efforts consistent with their normal trading and sales practices to sell such shares up to the amount specified on such terms. The obligations of each of the Sales Agents under the sales agreement to sell our common stock are subject to a number of customary conditions that we must meet. We may instruct each of the Sales Agents not to sell our common stock if the sales cannot be effected at or above the price designated by us in any such instruction. We and each of the Sales Agents may suspend the offering of common stock upon proper notice to the other party and subject to other conditions. We and each of the Sales Agents each have the right, by giving written notice as specified in the Sales Agreement, to terminate the Sales Agreement in each party’s sole discretion at any time upon three days’ prior notice.

Unless otherwise specified in the applicable placement notice, settlement for shares of our common stock will occur on the trading day following the date on which the sales are made. Sales of our common stock as contemplated in this prospectus will be settled through the facilities of The Depository Trust Company or by such other means as we and the Sales Agents may agree upon. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

We will pay the Sales Agents a commission for their services in acting as agent in the sale of common stock at a commission rate, in the aggregate, of up to 3% of the gross proceeds from each sale. We also agreed to reimburse the Sales Agents for certain specified fees and documented expenses, including the fees and documented expenses of their legal counsel in an aggregate amount not to exceed $50,000, plus an additional amount not to exceed $3,000 per fiscal quarter, or $12,000 in any given twelve (12) month period, on an ongoing basis during the term of the Sales Agreement, as provided in the sales agreement. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. We estimate that the total expenses for the offering, excluding compensation payable to the Sales Agents and expense reimbursement under the terms of the Sales Agreement, will be up to approximately $475,000.

In addition, the sales agreement provides that we will not (i) take any action designed to cause or result in, or that constitutes or would reasonably be expected to constitute, the stabilization or manipulation of the price of any of our securities to facilitate the sale or resale of common stock, or (ii) sell, bid for, or purchase common stock in violation of Regulation M, or pay anyone any compensation for soliciting purchases of the common stock under the Sales Agreement other than the Sales Agents.

In connection with the sale of the common stock on our behalf, each of the Sales Agents will be deemed to be an “underwriter” within the meaning of the Securities Act as amended, and their compensation will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to each of the Sales Agents with respect to certain liabilities, including civil liabilities under the Securities Act. The Sales Agents are not required to sell any certain number of shares or dollar amount of our common stock, but will use its commercially reasonable efforts consistent with its normal trading and sales practices to sell on our behalf all of the shares of common stock requested to be sold by us, subject to the conditions set forth in the Sales Agreement.

The offering of our common stock pursuant to the sales agreement will terminate upon the earlier of (1) the issuance and sale of all common stock subject to the Sales Agreement; and (2) the termination of the Sales Agreement as described therein.

B. Riley Securities has in the past, and each of the Sales Agents and their affiliates may in the future, provide various investment banking and/or other financial services for us and/or our affiliates, for which services they may in the future receive customary fees. To the extent required by Regulation M under the Exchange Act, the Sales Agents will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus. This summary of the material provisions of the sales agreement does not purport to be a complete statement of its terms and conditions. A copy of the Sales Agreement is filed with the SEC as an exhibit to the registration statement of which this prospectus is a part. See “Where You Can Find Additional Information” below.

This prospectus supplement and the accompanying prospectus in electronic format may be made available on a website maintained by each of the Sales Agents, and the Sales Agents may distribute the prospectus supplement and the accompanying prospectus electronically.

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LEGAL MATTERS

Certain legal matters will be passed upon for us by Thompson Hine LLP, New York, New York. The Sales Agents are being represented in connection with this offering by Ellenoff Grossman & Schole LLP, New York, New York.

EXPERTS

The 2025 and 2024 audited annual consolidated financial statements of Vaxart, Inc. as of and for each of the years in the two-year period ended December 31, 2025, incorporated by reference in this prospectus supplement and elsewhere in the registration statement, have been incorporated by reference in reliance upon the report of WithumSmith+Brown, PC, independent registered public accounting firm, upon the authority of said firm as experts in accounting and auditing.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act, with respect to the securities being offered by this prospectus supplement. This prospectus supplement does not contain all of the information in the registration statement and its exhibits. For further information with respect to us and the securities offered by this prospectus supplement, we refer you to the registration statement and its exhibits. Statements contained in this prospectus supplement as to the contents of any contract or any other document referred to are not necessarily complete, and in each instance, we refer you to the copy of the contract or other document filed as an exhibit to the registration statement. Each of these statements is qualified in all respects by this reference. The SEC maintains an internet website that contains reports, proxy statements, and other information about registrants, like us, that file electronically with the SEC. The address of that website is www.sec.gov. The information contained in, or that can be accessed through, the SEC’s website is not incorporated by reference in, and is not part of, this prospectus supplement.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus supplement. Information in this prospectus supplement supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus supplement, while information that we file later with the SEC will automatically update and supersede the information in this prospectus supplement to the extent that a statement contained in this prospectus supplement or free writing prospectus provided to you in connection with this offering, or in any other document we subsequently file with the SEC that also is incorporated by reference in this prospectus supplement, modifies or supersedes the original statement.

The following documents filed with the SEC are hereby incorporated by reference in this prospectus supplement:

	●	our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the SEC on March 13, 2026; and

	●	the description of our common stock contained in our Registration Statement on Form 10, filed with the SEC on May 4, 1970, as amended by our Current Report on Form 8-K (File No. 000-04829) filed with the SEC on August 15, 2003.

All reports and other documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the termination of this offering shall be deemed to be incorporated by reference in this prospectus supplement and to be part hereof from the date of filing of such reports and other documents.

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Up to $49,772,479 of Shares

Common Stock

PROSPECTUS SUPPLEMENT

Citizens Capital Markets

B. Riley Securities

__________, 2026

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PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The following table sets forth the costs and expenses, other than the underwriting discounts and commissions, payable by the registrant in connection with the offering of the securities pursuant to this registration statement:

SEC registration fee	$	24,604.78
Accounting fees and expenses		*
Legal fees and expenses		*
Printing and miscellaneous expenses		*
Total	$	*

*	These fees and expenses depend on the securities offered and the number of issuances, and accordingly cannot be estimated as of the date of this prospectus.

Item 15. Indemnification of Officers and Directors.

Section 145 of the Delaware General Corporation Law authorizes a court to award, or a corporation’s board of directors to grant, indemnity to directors and officers in terms sufficiently broad to permit such indemnification under certain circumstances for liabilities, including reimbursement for expenses incurred, arising under the Securities Act.

Our restated certificate of incorporation, as amended, and amended and restated bylaws provide that we will indemnify our directors and officers, and may indemnify our employees and other agents, to the fullest extent permitted by the Delaware General Corporation Law. However, Delaware law prohibits our certificate of incorporation from limiting the liability of our directors for the following:

	●	any breach of the director’s duty of loyalty to us or to our stockholders;

	●	acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

	●	unlawful payment of dividends or unlawful stock repurchases or redemptions; and

	●	any transaction from which the director derived an improper personal benefit.

We maintain insurance policies that indemnify our directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any director or officer in his capacity as such. We have obtained director and officer liability insurance to cover liabilities our directors and officers may incur in connection with their services to us.

In any underwriting agreement we enter into in connection with the sale of our common stock being registered hereby, the underwriters will agree to indemnify, under certain circumstances, us, our officers, our directors, and our controlling persons within the meaning of the Securities Act, against certain liabilities.

Item 16. Exhibits

See the Exhibit Index on the page immediately following the signature page to this registration statement for a list of exhibits filed as part of this registration statement, which Exhibit Index is incorporated herein by reference.

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Item 17. Undertakings

(a) The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Filing Fee Tables” table in the effective Registration Statement.

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement;

provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the registration statement is on Form S-3 and information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the Registration Statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the Registration Statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new Registration Statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the Registration Statement as of the date the filed prospectus was deemed part of and included in the Registration Statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a Registration Statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the Registration Statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the Registration Statement relating to the securities in the Registration Statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a Registration Statement or prospectus that is part of the Registration Statement or made in a document incorporated or deemed incorporated by reference into the Registration Statement or prospectus that is part of the Registration Statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the Registration Statement or prospectus that was part of the Registration Statement or made in any such document immediately prior to such effective date.

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(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this Registration Statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of section 310 of the Trust Indenture Act (“Trust Indenture Act”) in accordance with the rules and regulations prescribed by the Commission under section 305(b)(2) of the Trust Indenture Act.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC 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 registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant 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 indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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EXHIBIT INDEX

Exhibit Number	Description of Document
1.1*	Form of Underwriting Agreement
1.2	At the Market Offering Agreement, dated March 21, 2025, between Vaxart, Inc., Citizens JMP Securities, LLC, and B. Riley Securities, Inc (incorporated by reference to Exhibit 1.1 to the Current Report on Form 8-K (001-35285) filed on March 21, 2025)
4.1	Specimen Common Stock Certificate of the Company (incorporated by reference to Exhibit 4.2 to the Registration Statement on Form S-3 (Commission File No. 333-228910), filed on December 20, 2018)
4.2	Form of Indenture
4.3*	Form of Debt Security
4.4*	Form of Certificate of Designation
4.5*	Form of Preferred Stock Certificate
4.6*	Form of Warrant Agreement
4.7*	Form of Purchase Contract Agreement
4.8*	Form of Unit Certificate
5.1	Opinion of Thompson Hine LLP
23.1	Consent of Thompson Hine LLP (included in Exhibit 5.1)
23.2	Consent of WithumSmith+Brown, PC, Independent Registered Public Accounting Firm
24.1	Power of Attorney (included on signature page)
25.1*	Form T-1 Statement of Eligibility of Trustee under the Indenture
107	Filing Fee Table

* To be filed by amendment or incorporated by reference in connection with the offering of the securities.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Francisco, State of California, on April 15, 2026.

	VAXART, INC.


	By:	/s/ Steven Lo
		Steven Lo
		President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Steven Lo and Jeroen Grasman, and each of them, as his or her true and lawful attorneys-in-fact and agents, each with the full power of substitution, for him or her and in his or her name, place or stead, in any and all capacities, to sign any and all amendments to this registration statement (including post-effective amendments), and to sign any registration statement for the same offering covered by this registration statement that is to be effective upon filing pursuant to Rule 462(b) promulgated under the Securities Act, and all post-effective amendments thereto, and to file or cause to be filed the same, with exhibits thereto and other documents in connection therewith, with the U.S. Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, and hereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date

/s/ Steven Lo	President, Chief Executive Officer, and	April 15, 2026
Steven Lo	Member of the Board of Directors
	(Principal Executive Officer)

/s/ Jeroen Grasman	Chief Financial Officer	April 15, 2026
Jeroen Grasman	(Principal Financial and Accounting Officer)


/s/ Kevin P. Finney	Member of the Board of Directors	April 15, 2026
Kevin P. Finney

/s/ Elaine J. Heron	Member of the Board of Directors	April 15, 2026
Elaine J. Heron, Ph.D.

/s/ W. Mark Watson	Member of the Board of Directors	April 15, 2026
W. Mark Watson

/s/ David Wheadon	Member of the Board of Directors	April 15, 2026
David Wheadon, M.D.

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SEC Form S-3 filed by Vaxart Inc