Form 8-K

8-K — OS Therapies Inc

Accession: 0001213900-26-098880

Filed: 2026-09-10

Period: 2026-09-10

CIK: 0001795091

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — ea0305135-8k_ostherapies.htm (Primary)

EX-5.1 — OPINION OF OLSHAN FROME WOLOSKY LLP (ea0301513501ex5-1.htm)

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8-K — CURRENT REPORT

8-K (Primary)

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0001795091

2026-09-10

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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): September 10, 2026

OS THERAPIES INCORPORATED

(Exact

name of registrant as specified in its charter)

Delaware

001-42195

82-5118368

(State

or other jurisdiction

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 ☒

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

Therapies Incorporated

September

10, 2026

Item

8.01. Other Events.

September 10, 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

25, 2025. The Prospectus Supplement covers the resale from time to time of up to 5,874,094 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: September 10, 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: ea0301513501ex5-1.htm · Sequence: 2

Exhibit 5.1

September 10, 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 September

10, 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 25, 2025, relating

to the offer and resale from time to time by the selling stockholders identified in the Prospectus Supplement of up to 5,874,094 shares

of the Company’s common stock, par value $0.001 per share (the “Common Stock”), consisting of (i) 600,000 shares of

Common Stock (the “Shares”), (ii) 900,000 shares of Common Stock (the “Pre-Funded Warrant Shares”) issuable upon

exercise of certain of the Company’s outstanding pre-funded warrants (the “Pre-Funded Warrants”), (iii) 1,500,000 shares

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

“Warrants”) and (iv) 2,874,094 shares of Common Stock (the “Conversion Shares”) issuable upon conversion of the

Company’s outstanding senior secured 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 Pre-Funded Warrants, (d) the Warrants, (e) the Notes, (f) the Company’s Third

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

to date, and (h) 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;

(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 Pre-Funded Warrant and 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 Pre-Funded Warrant or Warrant, as applicable, to be performed

by it, that the representations and warranties of each such party as set forth in such Pre-Funded Warrant or Warrant, as applicable, when

made were, and on the date hereof are, true and complete, and that such Pre-Funded Warrant or Warrant, as applicable 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 Pre-Funded Warrant Shares and the Warrant Shares.

September 10, 2026

Page 2

Based upon the foregoing and

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

1. The Shares have been duly authorized and are validly issued, fully paid and nonassessable.

2. The Pre-Funded Warrant Shares have been duly authorized and, when issued, delivered and paid for upon

valid exercise in accordance with the terms of the applicable Pre-Funded Warrant, will be validly issued, fully paid and nonassessable.

3. 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.

4. 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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