Form 8-K

8-K — OS Therapies Inc

Accession: 0001213900-26-037476

Filed: 2026-03-31

Period: 2026-03-31

CIK: 0001795091

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — ea0283924-8k_ostherapies.htm (Primary)

EX-5.1 — OPINION OF OLSHAN FROME WOLOSKY LLP (ea028392401ex5-1.htm)

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8-K — CURRENT REPORT

8-K (Primary)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

March 31, 2026

OS THERAPIES

INCORPORATED

(Exact name of registrant as specified in its charter)

Delaware

001-42195

82-5118368

(State or other jurisdiction

of incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

115 Pullman Crossing Road, Suite 103

Grasonville, Maryland

21638

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s telephone number, including

area code: (410) 297-7793

N/A

(Former name or former address, if changed since

last report.)

Check the appropriate box below if the Form 8-K

filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General

Instruction A.2. below):

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class

Trading Symbol(s)

Name of Each Exchange on Which Registered

Common Stock, par value $0.001 per share

OSTX

NYSE American

Indicate by check mark whether the registrant

is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the

Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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 13(a) of the Exchange Act. ☐

CURRENT REPORT ON FORM 8-K

OS Therapies Incorporated

March 31, 2026

Item 8.01. Other Events.

On March 31, 2026, OS Therapies

Incorporated (the “Company”) filed with the U.S. Securities and Exchange Commission (the “SEC”) a prospectus supplement

(the “Prospectus Supplement”), which forms a part of the Company’s registration statement on Form S-3 (File No. 333-289443),

which was previously filed with the SEC on August 8, 2025 and declared effective on August 12, 2025. The Prospectus Supplement covers

the resale from time to time of up to 10,529,417 shares of the Company’s common stock (the “Shares”) by the selling

stockholders referenced in the Prospectus Supplement. The Company is filing this Current Report on Form 8-K to provide the legal

opinion of its counsel, Olshan Frome Wolosky LLP, regarding the legality of Shares, which is attached hereto as Exhibit 5.1.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

Number

Description

5.1

Opinion of Olshan Frome Wolosky LLP.

23.1

Consent of Olshan Frome Wolosky LLP (included in its opinion filed as Exhibit 5.1).

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements

of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto

duly authorized.

OS THERAPIES INCORPORATED

Dated: March 31, 2026

By:

/s/ Paul A. Romness, MPH

Name:

Paul A. Romness, MPH

Title:

President and Chief Executive Officer

EX-5.1 — OPINION OF OLSHAN FROME WOLOSKY LLP

EX-5.1

Filename: ea028392401ex5-1.htm · Sequence: 2

Exhibit 5.1

March 31, 2026

OS Therapies Incorporated

115 Pullman Crossing Road, Suite #103

Grasonville, Maryland 21638

Ladies and Gentlemen:

We are acting as counsel to

OS Therapies Incorporated, a Delaware corporation (the “Company”), in connection with the prospectus supplement dated March

31, 2026 (the “Prospectus Supplement”) constituting a part of the Registration Statement on Form S-3 initially filed by the

Company with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Act”),

on August 8, 2025 (as it may be amended, the “Registration Statement”), which became effective on August 12, 2025, relating

to the offer and resale from time to time by the selling stockholders identified in the Prospectus Supplement of up to 10,529,417 shares

of the Company’s common stock, par value $0.001 per share (the “Common Stock”), consisting of (i) 4,289,441 shares of

Common Stock (the “Warrant Shares”) issuable upon exercise of certain of the Company’s outstanding warrants (the “Warrants”)

and (ii) 6,239,976 shares of Common Stock (the “Conversion Shares”) issuable upon conversion of the Company’s outstanding

unsecured convertible promissory notes (the “Notes”).

We advise you that we have

examined executed originals or copies certified or otherwise identified to our satisfaction of the following documents: (a) the Registration

Statement, (b) the Prospectus Supplement, (c) the Warrants, (d) the Notes, (e) the Company’s Third Amended and Restated Certificate

of Incorporation, as amended to date, (f) the Company’s Amended and Restated Bylaws, as amended to date, and (g) certain resolutions

adopted by the Board of Directors of the Company. In addition, we have examined and relied upon such corporate records and other documents,

instruments and certificates of officers and representatives of the Company and of public officials, and we have made such examination

of law, as we have deemed necessary or appropriate for purposes of the opinions expressed below. As to certain factual matters, unless

otherwise indicated, we have relied, to the extent we have deemed proper, on certificates of certain officers of the Company.

We have assumed for purposes

of rendering the opinions set forth herein, without any verification by us:

(i) the genuineness of all signatures, the legal capacity of all

natural persons to execute and deliver documents, the authenticity and completeness of documents submitted to us as originals and the

completeness and conformity with authentic original documents of all documents submitted to us as copies, that all documents, books and

records made available to us by the Company are accurate and complete;

March 31, 2026

Page 2

(ii) that each Note has been duly authorized, executed and delivered by each party thereto, that each such

party is duly organized, validly existing and in good standing under the laws of its jurisdiction of organization and all jurisdictions

where it is conducting business or otherwise required to be so qualified, that each such party has full power, authority and legal right

to enter into and perform the terms and conditions of such Note to be performed by it, that the representations and warranties of each

such party as set forth in such Note when made were, and on the date hereof are, true and complete, and that such Note constitutes a legal,

valid and binding obligation of each such party, enforceable against it in accordance with their respective terms and that the Company

received the requisite approval from the NYSE American to list the Conversion Shares; and

(iii) that each Warrant has been duly authorized, executed and delivered by each party thereto, that each such

party is duly organized, validly existing and in good standing under the laws of its jurisdiction of organization and all jurisdictions

where it is conducting business or otherwise required to be so qualified, that each such party has full power, authority and legal right

to enter into and perform the terms and conditions of such Warrant to be performed by it, that the representations and warranties of each

such party as set forth in such Warrant when made were, and on the date hereof are, true and complete, and that such Warrant constitutes

a legal, valid and binding obligation of each such party, enforceable against it in accordance with their respective terms and that the

Company received the requisite approval from the NYSE American to list the Warrant Shares.

Based upon the foregoing and

subject to the qualifications, assumptions and limitations contained herein, we are of the opinion that:

1. The Warrant Shares have been duly authorized and, when issued, delivered and paid for upon valid exercise

in accordance with the terms of the applicable Warrant, will be validly issued, fully paid and nonassessable.

2. The Conversion Shares have been duly authorized and, when issued and delivered upon valid conversion in

accordance with the terms of the applicable Note, will be validly issued, fully paid and nonassessable.

We are members of the Bar

of the State of New York. We do not express any opinion as to the effect of any laws other than the laws of the State of New York and

the General Corporation Law of the State of Delaware, and the federal laws of the United States of America, as in effect on the date hereof.

This opinion letter is limited

to the matters set forth herein, and no opinion may be inferred or implied beyond the matters expressly set forth herein. This opinion

letter is not a guaranty nor may one be inferred or implied. This opinion letter speaks as of the date hereof and we assume no obligation

to update or supplement this opinion letter to reflect any facts or circumstances that may hereafter come to our attention or any changes

in fact or law that may hereafter occur.

We hereby consent to the filing

of this opinion in accordance with the requirements of Item 601(b)(5) of Regulation S-K promulgated under the Act with the Commission

as an exhibit to the Current Report on Form 8-K filed by the Company with the Commission on the date hereof and to the reference made

to this firm under the caption “Legal Matters” in the Prospectus Supplement. In giving such consent, we do not hereby admit

that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission.

Very truly yours,

/s/ Olshan Frome Wolosky LLP

OLSHAN FROME WOLOSKY LLP

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