Document

424B4 1 slrxdecoyfinal424b4.htm 424B4 Document


PROSPECTUS			Filed pursuant to Rule 424(b)(4)
			Registration No. 333-284368

2,514,335 Shares of Common Stock,

Pre-Funded Warrants to Purchase up to 2,152,331 Shares of Common Stock,

Series A Warrants to Purchase up to 4,666,666 Shares of Common Stock,

Series B Warrants to Purchase up to 4,666,666 Shares of Common Stock,

Representative Warrants to Purchase up to 233,333 Shares of Common Stock,

and

Up to 11,718,996 Shares of Common Stock Issuable Upon Exercise of Pre-Funded Warrants, Series A Warrants, Series B Warrants and Representative Warrants

Salarius is offering 2,514,335 shares of its common stock, par value $0.0001 per share (the “common stock”), Series A Warrants to purchase up to 4,666,666 shares of its common stock which will expire five (5) years from the date of issuance (the “Series A Warrants”) and Series B Warrants to purchase up to 4,666,666 shares of its common stock which will expire one (1) year from the date of issuance (the “Series B Warrants” and, together with the Series A Warrants, the “common warrants”) at a combined public offering price of $1.50 per share of common stock and accompanying common warrants.

The common warrants will be exercisable upon issuance. See “Description of Securities Salarius is Offering” on page 89 of this prospectus for more information regarding the terms of the common warrants.

Salarius is also offering to certain purchasers whose purchase of shares of common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of Salarius’ outstanding common stock immediately following the consummation of this offering, the opportunity to purchase, if any such purchaser so chooses, up to 2,152,331 pre-funded warrants to purchase shares of common stock, in lieu of shares of common stock. The purchase price of each pre-funded warrant (and accompanying common warrants) will be equal to the public offering price for the common stock (and accompanying common warrants) in this offering, minus $0.0001. Each pre-funded warrant is exercisable for one (1) share of Salarius’ common stock and has an exercise price of $0.0001 per share. Each pre-funded warrant will be exercisable at any time after the date of issuance.

The common stock (or pre-funded warrants) and the common warrants will be sold in combination, with each share of common stock (or pre-funded warrant to purchase one share of common stock) accompanied by one Series A Warrant to purchase one share of common stock, and one Series B Warrant to purchase one share of common stock. This prospectus also relates to the offering of common stock issuable upon exercise of the pre-funded warrants and common warrants. Salarius collectively refers to the shares of common stock, pre-funded warrants and common warrants offering hereby, including the shares of common stock underlying the pre-funded warrants and common warrants, as the “securities.”

Salarius and Decoy Therapeutics Inc. (“Decoy”) have entered into an Agreement and Plan of Merger, dated January 10, 2025 and amended on March 28, 2025, June 10, 2025, July 18, 2025, July 29, 2025 and September 17, 2025 (as amended, the “Merger Agreement”), pursuant to which wholly owned subsidiaries of Salarius will merge with and into Decoy, with Decoy surviving as a wholly owned subsidiary of Salarius (the “Merger”). The Decoy transaction is structured as a two-step transaction. In step one of the transaction, the Merger will be consummated and all of Decoy’s outstanding equity interests will be exchanged based on an exchange ratio for consideration of shares of Salarius’ Series A Preferred Stock. Additionally, certain holders of Decoy’s non-convertible promissory notes (the “Decoy Promissory Notes”) will exchange their notes for shares of Salarius’ Series B Preferred Stock pursuant to note exchange agreements entered into in connection with the Merger, with the closing of such exchange to occur at the Merger Closing. The Series A Preferred Stock and the Series B Preferred Stock are newly designated series of preferred stock (collectively, the “Preferred Stock”) that are intended to have economic rights equivalent to the Salarius common stock, but with only limited voting rights. The Series B Preferred Stock is identical in all material respects to the Series A Preferred Stock, except for certain redemption and conversion provisions that require (i) fifty percent (50%) of net proceeds from Salarius’ “at-the-market” equity program and equity line of credit to be used for mandatory redemption of the Series B Preferred Stock until fully redeemed, (ii) optional redemption allowing Salarius to redeem all or any portion of the outstanding Series B Preferred Stock at any time following the Merger Closing, and (iii) optional conversion at the discretion of the holders upon stockholder approval of the conversion of the Series B Preferred Stock and Salarius’ achievement of the Nasdaq initial listing standards for a period of one year following such approvals, at which time remaining shares of Series B Preferred Stock shall automatically convert into Company common stock at the conversion ratio. The number of shares of common stock to be issued at the closing of the Merger (the “Merger Closing”) and the number of shares of Salarius common stock underlying the Series A Preferred Stock and Series B Preferred Stock to be issued at Merger Closing is based on an exchange ratio set forth in the Merger Agreement that, before taking into account the dilutive effects of this offering and after giving effect to the expected adjustment to the conversion ratio of the Preferred Stock based on the offering price of $1.50 per share in this offering, would result in Salarius’ legacy stockholders retaining approximately 17.9% of Salarius and Decoy stockholders owning approximately 82.1% of Salarius.

Based on the exchange ratio, the total number of shares underlying the Series A Preferred Stock and the Series B Preferred Stock at the Merger Closing will initially be 1,719,324 shares of common stock. However, the Series A Preferred Stock and the Series B Preferred Stock contain price protection provisions such that the conversion ratio (initially 1:1,000) will be adjusted such that the number of shares of common stock underlying each share of Preferred Stock will be equal to the product of 1,000 multiplied by a fraction, the numerator of which is $10.50 (the “Initial Issuance Price”) and the denominator of which is the effective per share price in this offering or any future financing, provided that in no event will the denominator be less than $3.75 (the “Floor Price”). Accordingly, the number of shares of Salarius common stock issuable upon conversion of the Preferred Stock may be much higher, up to a maximum of 4,814,106 shares of Salarius common stock, which would occur if the per share price in this offering or any future financing is equal to or lower than $3.75. Based on the offering price of $1.50 per share in this offering, the number of shares of Salarius common stock underlying the Preferred Stock is expected to be 4,814,106 shares of Salarius common stock.

The Merger Closing contemplated by step one of the transaction is conditioned upon, among other things, minimum proceeds from financings of at least $6.0 million (collectively, the “Qualified Financing”) and the continued listing of Salarius common stock on Nasdaq. Salarius has already satisfied the requirement of a Qualified Financing and the Merger Closing is expected to occur concurrently with the closing of this financing. For the avoidance of doubt, while the Merger Closing contemplated by step one of the transaction is conditioned on Salarius’ continued listing on Nasdaq, neither this financing nor such Merger Closing is contingent on Nasdaq’s approval of an initial listing application, which is expected to be filed following the consummation of this financing and the Merger Closing in connection with step two of the transaction.

In step two of the Decoy transaction, Salarius has agreed to call a special stockholder meeting to approve, among other things, the conversion of the Preferred Stock to be issued at Merger Closing into shares of Salarius common stock (the “Conversion Proposal”). The Preferred Stock issued at the Merger Closing will not convert into Salarius common stock until Salarius obtains stockholder approval to approve the Conversion Proposal. Nasdaq has informed Salarius that the Decoy transaction constitutes a business combination that will result in a “Change of Control” pursuant to Listing Rule 5110(a) in connection with step two of the transaction and that the post-transaction entity will be required to satisfy all of Nasdaq’s initial listing criteria and to complete Nasdaq’s initial listing process prior to Salarius’ stockholder meeting to seek approval for the Conversion Proposal. Salarius therefore intends to commence the initial listing process following the consummation of this financing and the Merger Closing at such time that the post-transaction entity is expected to satisfy all of the applicable Nasdaq initial listing criteria. The Preferred Stock issued at the Merger Closing in connection with step one of the Decoy transaction will not be convertible into Salarius common stock until Nasdaq’s approval of the initial listing application and stockholder approval of the Conversion Proposal. Please see “Prospectus Summary – Recent Developments - Description of the Merger with Decoy” and “Prospectus Summary – Recent Developments – Summary of Transaction Steps” for more information.

Salarius’ common stock is listed on Nasdaq under the symbol “SLRX.” There is no established trading market for the pre-funded warrants or common warrants, and Salarius does not expect a market to develop. Salarius does not intend to apply for a listing of the pre-funded warrants or common warrants on any securities exchange or other nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants or common warrants will be limited.


	Per Share and Accompanying Common Warrants		Per Pre-Funded Warrant and Accompanying Common Warrants		Total
Public offering price(1)	$	1.50	$	1.4999	$	6,999,783.77
Underwriting discounts and commissions(1)(2)	$	0.135	$	0.134991	$	629,980.54
Proceeds to Salarius, before expenses(3)	$	1.365	$	1.364909	$	6,369,803.23

__________________

(1)The public offering price and underwriting discount corresponds to (i) a public offering price per share of common stock of $1.48 ($1.3468 net of the underwriting discount) or $1.4799 per pre-funded warrant ($1.346709 net of the underwriting discount), (ii) a public offering price per one Series A Warrant of $0.01 ($0.0091 net of the underwriting discount) and (iii) a public offering price per one Series B Warrant of $0.01 ($0.0091 net of the underwriting discount).

(2)Salarius has agreed to reimburse the representative for certain expenses. See “Underwriting” on page 102 for additional information regarding underwriting compensation.

(3)The above summary of offering proceeds does not give effect to any proceeds from the exercise of any warrants being issued in this offering.

Salarius has granted a 45-day option to the underwriters to purchase up to 699,999 shares of Salarius’ common stock, and/or Series A Warrants to purchase up to 699,999 shares of Salarius’ common stock, and/or Series B Warrants to purchase up to 699,999 shares of Salarius’ common Stock at their respective public offering prices, less the underwriting discounts and commissions. The option may be used to purchase such shares of common stock and/or common warrants, or any combination thereof, as determined by the underwriters.

Salarius has agreed to issue to the representative warrants to purchase the number of shares of Salarius common stock equal to 5% of the aggregate number of shares of common stock and/or pre-funded warrants sold in this offering (the “representative warrants”). The representative warrants will have an exercise price of $2.325 and will be exercisable for five (5) years from the commencement of sales of the offering.

The underwriters expect to deliver the securities to the purchasers in the offering on or about November 12, 2025.

You should also read this prospectus, together with additional information described under the heading “Where You Can Find More Information” carefully before you invest in any of Salarius’ securities.

Salarius is a “smaller reporting company” as defined under the federal securities laws and, as such, Salarius has elected to comply with certain reduced public company reporting requirements for this prospectus, the documents incorporated by reference herein and future filings. Please see “Prospectus Summary – Implications of Being a Smaller Reporting Company.”

Investing in Salarius’ securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading “Risk Factors” beginning on page 34 of this prospectus, and under similar headings in any amendments or supplements to this prospectus or in any other documents incorporated by reference into this prospectus.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ADEQUACY OR ACCURACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

Ladenburg Thalmann

The date of this prospectus is November 11, 2025.

TABLE OF CONTENTS


			Page
About this Prospectus			1
Special Note Regarding Forward-Looking Statements			3
Prospectus Summary			7
Selected Historical and Unaudited Pro-Forma Condensed Combined Financial Data			22
The Offering			30
Risk Factors			34
Use of Proceeds			71
Market Price Information			73
Dividend Policy			74
Capitalization			75
Dilution			77
Principal Stockholders of Salarius			79
Principal Stockholders of the Combined Company			81
Description of Capital Stock			83
Description of Securities Salarius is Offering			89
Material U.S Federal Income Tax Consequences			94
Underwriting			102
Legal Matters			107
Experts			107
Where You Can Find More Information			107
Incorporation of Certain Information by Reference			108
Unaudited Pro Forma Consolidated Combined Financial Information			109

References to “Salarius” and “Decoy” in this prospectus refer to Salarius Pharmaceuticals, Inc. and Decoy Therapeutics, Inc., respectively. References to the “combined company” refer to Salarius and its wholly owned subsidiary, Decoy, after the Merger, assuming the Merger is consummated. Except as otherwise noted, references to “we,” “us” or “our” refer to Salarius. References to “First Merger Sub” refer to Decoy Therapeutics MergerSub I, Inc., a newly formed, wholly owned subsidiary of Salarius and references to “Second Merger Sub” refer to Decoy Therapeutics MergerSub II, LLC, a newly formed, wholly owned subsidiary of Salarius.

References to the “Merger Agreement” refer to that certain Agreement and Plan of Merger dated as of January 10, 2025, among Salarius, First Merger Sub, Second Merger Sub and Decoy, as amended from time to time. References to the “Merger” refers collectively to the merger of First Merger Sub with and into Decoy, with Decoy surviving as the surviving entity and as a wholly owned subsidiary of Salarius, and the merger of Decoy with and into Second Merger Sub, with Second Merger Sub being the surviving entity and continuing under the name “Decoy Therapeutics, LLC” as a wholly owned subsidiary of Salarius, in each case as contemplated under the Merger Agreement.

ABOUT THIS PROSPECTUS

Salarius incorporates by reference important information into this prospectus. You may obtain the information incorporated by reference without charge by following the instructions under “Incorporation of Certain Information by Reference.” You should carefully read this prospectus as well as additional information described under “Incorporation of Certain Information by Reference,” before deciding to invest in Salarius’ securities.

Neither Salarius nor the underwriters have authorized anyone to provide any information other than that contained or incorporated by reference in this prospectus or in any free writing prospectus that Salarius has authorized for use in connection with this offering. Salarius takes no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you.

This prospectus does not constitute an offer to sell, or a solicitation of an offer to purchase, the securities offered by this prospectus in any jurisdiction to or from any person to whom or from whom it is unlawful to make such offer or solicitation of an offer in such jurisdiction.

The underwriters are offering to sell, and seeking offers to buy, Salarius’ securities only in jurisdictions where offers and sales are permitted. The information contained in this prospectus and any free writing prospectus that Salarius has authorized for use in connection with this offering is accurate only as of the respective dates thereof, and the information in the documents incorporated by reference in this prospectus is accurate only as of the date of those respective documents, regardless of the time of delivery of this prospectus or of any sale of Salarius’ securities. Salarius’ business, financial condition, results of operations, and prospects may have changed since such dates. It is important for you to read and consider all information contained or incorporated by reference in this prospectus in making your investment decision. You should read both this prospectus, as well as the documents incorporated by reference into this prospectus and the additional information described under “Incorporation of Certain Information by Reference” in this prospectus, before investing in Salarius’ securities.

Unless otherwise indicated, information contained in or incorporated by reference into this prospectus concerning Salarius’ and Decoy’s respective businesses and the industries and markets in which they operate, including with respect to their business prospects, market position and opportunity, and the competitive landscape, is based on information from Salarius’ and Decoy’s respective management’s estimates, as well as from industry publications, surveys, and studies conducted by third parties. Salarius’ and Decoy’s respective management’s estimates are derived from publicly available information, their knowledge of the respective party’s business and industry, and assumptions based on such information and knowledge, which they believe to be reasonable. In addition, while Salarius and Decoy believe that information contained in the industry publications, surveys, and studies has been obtained from reliable sources, neither party has independently verified any of the data contained in these third-party sources, and the accuracy and completeness of the information contained in these sources is not guaranteed.

Although Salarius is not aware of any misstatements regarding the market and industry data presented in this prospectus and the documents incorporated herein by reference, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed under the heading “Risk Factors” in this prospectus and any related free writing prospectus and under similar headings in the other documents that are incorporated by reference into this prospectus, including in Salarius’ Annual Report on Form 10-K filed on March 21, 2025 and Salarius’ Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025 filed on May 14, 2025 and August 12, 2025, respectively. Accordingly, you should not place undue reliance on this information.

For investors outside the United States: Salarius and the underwriters have not done anything that would permit this offering or the possession or distribution of this prospectus in any jurisdiction where action for those purposes is required, other than in the United States. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the securities and the distribution of this prospectus outside of the United States.

Basis of Presentation

On June 14, 2024, Salarius filed a Certificate of Amendment to its amended and restated certificate of incorporation (the “2024 Certificate of Amendment”) with the Secretary of State of the State of Delaware to effect a 1-for-8 reverse stock split of Salarius’ issued and outstanding shares of common stock, par value $0.0001 per share (the “ 2024 reverse split”), which became effective on that date.

On August 15, 2025, Salarius filed a Certificate of Amendment to its amended and restated certificate of incorporation (the “Certificate of Amendment”) with the Secretary of State of the State of Delaware to effect a 1-for-15 reverse stock split of Salarius’ issued and outstanding shares of common stock, par value $0.0001 per share (the “2025 reverse split” and together with the 2024 reverse split, the “reverse splits”), which became effective on that date. All historical share and per share amounts with respect to Salarius reflected throughout this prospectus have been adjusted to reflect the reverse splits.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents Salarius has filed with the SEC that are incorporated by reference in this prospectus contain “forward-looking statements” within the meaning of the U.S. federal securities laws, including the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements regarding the plans, strategies and prospects, both business and financial, of Salarius, Decoy and the combined company. These statements are based on the beliefs and assumptions of Salarius’ and Decoy’s management. Although Salarius and Decoy believe that these plans, intentions and expectations reflected in or suggested by these forward-looking statements are reasonable, the parties cannot assure you that they will achieve or realize these plans, intentions or expectations. Forward-looking statements are inherently subject to risks, uncertainties and assumptions. Generally, statements that are not historical facts, including statements concerning possible or assumed future actions, business strategies, events, or results of operations, are forward-looking statements. These statements may be preceded by, followed by or include the words “believes,” “estimates,” “expects,” “projects,” “target,” “goal,” “forecasts,” “may,” “will,” “potential,” “should,” “would,” “could,” “future,” “seeks,” “plans,” “predicts,” “propose,” “scheduled,” “anticipates,” “intends,” or similar expressions.

Forward-looking statements in this prospectus include, but are not limited to, statements about the following:

•the expected benefits of, and potential value created by, the Merger for the securityholders of Salarius and Decoy;

•the likelihood of the satisfaction of certain conditions to the completion of the Merger, including the conditions related to this offering, whether and when the Merger will be consummated and that Salarius’ common stock remains listed on Nasdaq;

•the effects of the Merger and this offering on the ownership percentages of the Decoy’s stockholders and Salarius’ stockholders in the combined company;

•Salarius’ expectations regarding the timing of the combined company’s ability to satisfy the Nasdaq initial listing standard and obtain stockholder approval for the conversion of the Preferred Stock into common stock in connection with step two of the Decoy transaction;

•the plans, strategies and objectives of management for future operations, including the execution of integration plans and the anticipated timing of filings, commencement of preclinical studies or clinical trials and release of data from such studies or trials;

•plans to develop and commercialize additional products candidates including planned preclinical, clinical, regulatory, commercialization and manufacturing activities;

•the attraction and retention of highly qualified personnel;

•the ability to protect and enhance the combined company’s products and intellectual property;

•developments and projections relating to the combined company’s competitors or industry;

•the combined company’s financial performance;

•Salarius’ or Decoy’s relationships and actions with third parties;

•Salarius’ and the combined company’s ability to maintain the listing of its shares of common stock on Nasdaq, and the potential liquidity and trading of such shares of common stock;

•the ability of Salarius and the combined company to successfully manage its cash and cash equivalents and any anticipated proceeds from this offering or other financing transactions;

•Salarius’ and the combined company’s ability to acquire sufficient sources of funding if and when needed;

•future regulatory, judicial and legislative changes in Salarius’ or Decoy’s respective industries; and

•the use of proceeds from this offering.

These forward-looking statements should not be relied upon as predictions of future events as Salarius and Decoy cannot assure you that the events or circumstances reflected in these statements will be achieved or will occur. You can identify forward-looking statements by the use of forward-looking terminology including “believes,” “expects,” “may,” “will,” “should,” “seeks,” “intends,” “plans,” “pro forma,” “estimates,” or “anticipates” or the negative of these words and phrases or other variations of these words and phrases or comparable terminology. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Actual results could differ materially from those contained in any forward-looking statement as a result of various factors, including, without limitation:

•Salarius’ and Decoy’s stockholders may not realize a benefit from the Merger commensurate with the ownership dilution they will experience in connection with the Merger and this offering;

•the Merger consideration may have greater or lesser value at the closing of the Merger than at the time the Merger Agreement was signed;

•failure to complete the Merger may result in either party paying a termination fee or expenses to the other party and could harm the future business and operations of each company;

•if the conditions to the Merger are not met the Merger may not occur;

•the timing of the consummation of the Merger is uncertain as is the ability of each of Salarius and Decoy to consummate the Merger;

•the Merger may be completed even though material adverse changes may occur;

•Salarius may not be able to correctly estimate its operating expenses and its expenses associated with the Merger and may have a significantly lower cash on the closing date of the Merger than currently estimated;

•Salarius may not be able to maintain its Nasdaq listing following the Merger Closing and may not be able to satisfy the initial listing standards;

•as a result of this financing, Salarius’ stockholders or Decoy’s stockholders are expected to own less of the combined company than is currently anticipated;

•the market price of Salarius’ common stock may decline following the Merger;

•restrictions in the Merger Agreement may prevent Salarius and Decoy from entering into a business combination with another party at a favorable price;

•certain provisions of the Merger Agreement may discourage third parties from submitting alternative takeover proposals, including proposals that may be superior to the arrangements contemplated by the Merger Agreement;

•the combined company may never earn a profit;

•the combined company will be subject to the uncertainties associated with the clinical development and regulatory approval of its product candidates including potential delays in the commencement, enrollment and completion of clinical trials and that the results of prior clinical trials may not be predictive of future results;

•the combined company will be required to raise additional funds to finance its operations and remain a going concern and may be required to do so sooner than it expects;

•the combined company may not be able to raise additional funds when necessary, and/or on acceptable terms;

•the combined company’s small public float, low market capitalization, limited operating history, and lack of revenue may make it difficult and expensive for the combined company to raise additional funds;

•Salarius and Decoy may not be able to protect their respective intellectual property rights;

•there may be changes in expected or existing competition for the combined company’s product candidates;

•the Merger will result in changes to the combined company’s board of directors that may affect the combined company’s business strategy and operations;

•both companies expect the price of the combined company’s common stock may be volatile and may fluctuate substantially following the Merger and the transactions contemplated thereby;

•if the combined company were to be delisted from Nasdaq, it would reduce the visibility, liquidity and price of its common stock;

•a significant portion of the combined company’s total outstanding shares of common stock may be sold into the public market at any point, which could cause the market price of the combined company’s common stock to drop significantly,

SEC Form 424B4 filed by Salarius Pharmaceuticals Inc.