UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of ~~October~~January ~~2025~~ 2026

Commission File Number: 001-38764

~~APTORUM~~Aptorum ~~GROUP~~Group ~~LIMITED~~Limited

17 Hanover Square

London W1S 1BN, United Kingdom

(Address of principal executive ~~offices~~office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F ☒ Form 40-F ☐

~~Registered~~EXPLANATORY ~~Direct Offering~~NOTE

OnAs ~~October~~previously 10disclosed, Aptorum ~~2025~~Group Limited, a Cayman Islands exempted company with limited liability (“Aptorum”, “APM,” “Aptorum Group” ~~Limited~~or (the “Company”) ~~entered~~and ~~into~~DiamiR ~~certain~~Biosciences ~~securities~~Corp., ~~purchase~~a ~~agreement~~Delaware ~~(the~~corporation (“~~Purchase Agreement~~DiamiR”), ~~with~~entered ~~certain~~into an ~~non-affiliated~~Agreement ~~institutional~~and ~~investors~~Plan of Merger on July 14, 2025, (the “~~Purchasers~~Merger Agreement”), pursuant to which, ~~the~~among ~~Company~~other ~~agreed~~matters, toAptorum ~~sell~~will form ~~(1)~~a 1direct,~~000,000 Class~~ Awholly ~~ordinary~~owned ~~shares~~subsidiary (in the state of Delaware (“~~Ordinary~~Merger ~~Shares~~Sub”), which will merge with and ~~(2)~~into inDiamR, with DiamiR surviving as a ~~concurrent~~wholly ~~private~~owned ~~placement,~~subsidiary ~~restricted~~of ~~warrants~~Aptorum, ~~to purchase~~and anthe ~~aggregate~~surviving corporation of upthe tomerger ~~2,000,000~~with ~~Ordinary~~the ~~Shares~~Merger Sub (the “~~Restricted Warrants~~Merger”); in addition to the requirement of obtaining Aptorum shareholder approval, ~~for~~the ~~aggregate~~closing ~~gross~~of ~~proceeds~~the Merger is subject to the satisfaction or waiver of ~~approximately~~each $2of ~~million~~the (other closing conditions set forth in the ~~“Offering”)~~Merger Agreement.

~~Each~~Aptorum ~~Restricted~~Group ~~Warrant~~Limited ~~is exercisable immediately as of~~ (the ~~date~~“Company”) ofis ~~issuance~~furnishing atthis anForm ~~exercise~~6-K ~~price~~to of(i) ~~$2.00~~provide ~~per Ordinary Share and expires twenty~~nine-~~four~~ months ~~from~~interim ~~the~~consolidated ~~effective date of~~financial astatements ~~registration~~ended ~~statement~~September ~~registering~~30, ~~for~~2025, ~~resale~~and ~~the~~to ~~Ordinary~~incorporate ~~Shares~~such ~~underlying~~consolidated ~~the~~financial ~~Restricted~~statements ~~Warrants.~~into ~~The~~the ~~Restricted~~Company’s ~~Warrants~~registration ~~and the~~statements ~~Ordinary~~referenced ~~Shares~~below, ~~issuable~~(ii) ~~upon~~to ~~the~~disclose ~~exercise~~and ofattach ~~the~~and ~~warrants~~incorporated ~~are~~by ~~not~~reference ~~being~~herein ~~registered~~DiamiR’s ~~under~~financial ~~the~~statements ~~Securities~~for ~~Act~~the ofquarter ended ~~1933~~November 30, as2025 ~~amended~~and ~~(the “Securities~~its ~~Act”)~~discussion and ~~are~~analysis ~~being~~of ~~offered~~its ~~pursuant~~financial tocondition anand ~~exemption~~results ~~from the registration requirements~~ of ~~the~~operations ~~Securities Act~~for ~~provided~~that insame ~~Section~~period 4and (aiii)~~(2)~~ ofprovide ~~the~~certain ~~Securities~~unaudited ~~Act~~pro ~~and/or~~forma ~~Rule~~condensed ~~506(b)~~combined offinancial ~~Regulation D~~statements.

~~The~~This ~~Company~~Form ~~agreed~~6-K inis hereby incorporated by reference into the ~~Purchase~~registration ~~Agreement~~statements ~~that it~~of ~~would~~the ~~not~~Company ~~issue~~on ~~any~~Form S-8 ~~Ordinary~~(Registration ~~Shares~~Number 333-232591), orForm F-3 ~~Ordinary~~(Registration ~~Share~~Number ~~Equivalents~~333-268873) ~~for~~and ~~thirty~~Form F-3 (30Registration Number 333-292793) ~~calendar~~and ~~days~~into ~~following~~each prospectus outstanding under the ~~closing~~foregoing ofregistration statements, to be a part thereof from the ~~Offering~~date on which this report is submitted, ~~subject~~ to ~~certain~~the ~~exceptions~~extent not superseded by documents or reports subsequently filed or furnished by the Company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended.

~~Concurrently~~Cautionary ~~with the execution of the Purchase~~Note ~~Agreement,~~Regarding ~~the officers and directors of the Company entered into lock~~Forward-upLooking agreements (the “Lock-Up Agreement”) pursuant to which they have agreed, among other things, not to sell or dispose of any Ordinary Shares which are or will be beneficially owned by them for thirty (30) days following the closing of the Offering.Statements

~~The~~This ~~Company~~Form ~~currently~~6-K ~~intends~~contains forward-looking tostatements ~~use~~within the ~~net~~meaning ~~proceeds~~of ~~from~~Section 27A of the Securities ~~Offering for~~Act ~~working~~of ~~capital~~1933, as amended, and ~~general~~Section ~~corporate~~21E ~~use~~of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). ~~Additionally~~Forward-looking statements include, ~~some~~without oflimitation, statements regarding the ~~proceeds~~financial ~~from~~position, financial performance, business strategy, expectations of our business and the ~~Offering~~plans and objectives ~~will~~of management for future operations. These statements constitute projections, forecasts and forward-looking statements, and are not guarantees of performance. Such statements can be ~~used~~identified toby ~~fund~~the ~~expenses~~fact ~~expected~~that they do not relate strictly to behistorical ~~incurred~~or current facts. When used in ~~connection~~this ~~with~~Form, including the ~~previously~~exhibits, ~~announced~~forward-looking ~~merger~~statements ~~between~~may be identified by the ~~Company~~use ~~and~~of ~~DiamiR~~words such as “estimate,” ~~Biosciences~~“plan,” ~~Corp.~~“project,” ~~and~~“forecast,” ~~for~~“intend,” ~~general~~“will,” ~~working~~“expect,” ~~capital~~“anticipate,” “believe,” of“seek,” ~~the~~“target,” ~~two~~“designed ~~companies~~to” ~~pending~~or ~~anticipated~~other ~~closing~~similar expressions that predict or indicate future events or trends or that are not statements of ~~the~~historical ~~merger~~facts. In addition, ~~which~~any isstatements ~~subject~~that refer to projections, ~~several~~forecasts ~~closing~~or ~~conditions~~other ~~and~~characterizations ~~therefore~~of ~~may~~future ~~never~~events ~~occur. The~~or ~~Offering~~circumstances, ~~closed~~including onany ~~October~~underlying 14assumptions, ~~2025~~are forward-looking statements.

~~H.C.~~Forward-looking ~~Wainwright~~statements are &subject ~~Co.,~~to ~~LLC,~~known ~~acted~~and asunknown ~~the~~risks and uncertainties and are based on potentially inaccurate assumptions that could cause actual results ~~exclusive~~to ~~placement~~differ ~~agent~~materially ~~(the~~from ~~“Placement~~those ~~Agent”),~~expected inor ~~connection~~implied ~~with~~by the ~~Offering~~forward-looking statements. ~~The~~Actual ~~Company~~results ~~agreed~~could todiffer ~~pay~~materially ~~the~~from those ~~Placement~~anticipated ~~Agent~~in anforward-looking ~~aggregate~~statements ~~fee~~for ~~equal~~many toreasons, ~~7.0%~~including of the ~~gross~~factors ~~proceeds~~discussed ~~raised~~under the “Risk Factors” section in the ~~Offering.~~Company’s ~~The~~Annual ~~Company~~Report ~~will~~on ~~also~~Form ~~pay~~20-F ~~the~~filed ~~Placement Agent~~with athe ~~management~~U.S. ~~fee~~Securities ~~equal~~and toExchange 1Commission.0% ofThese ~~the~~forward-looking ~~gross~~statements are ~~proceeds~~based ~~raised~~on ininformation available as of the ~~Offering~~date of this news release, $5and expectations,~~000~~ ~~for~~forecasts ~~non-accountable~~and ~~expenses,~~assumptions upas ~~to $50~~of that date,~~000~~ ~~for~~involve a ~~expenses~~number of ~~legal~~judgments, ~~counsel~~risks and ~~other~~uncertainties. ~~out~~Accordingly, forward-looking statements should not be relied upon as representing our views as of~~-pocket~~ ~~expenses~~any ~~and~~subsequent ~~$10~~date,~~000~~ ~~for~~and ~~clearing~~we ~~fees~~do ~~all~~not ~~associated~~undertake ~~with~~any ~~the Offering.~~obligation ~~After~~to ~~deducting~~update ~~fees~~forward-looking ~~due~~statements to ~~the~~reflect ~~Placement~~events ~~Agent~~or ~~and~~circumstances after ~~our~~the ~~estimated~~date ~~offering~~they ~~expenses~~were made, wewhether ~~expect~~as ~~the~~a ~~net~~result ~~proceeds~~of ~~from~~new ~~the Offering~~information, tofuture events or otherwise, except as may be ~~approximately~~required ~~US$1.725~~under ~~million~~applicable securities laws.

Copies of the form of the Purchase Agreement, form of Restricted Warrant, and form of Lock-Up Agreement are attached hereto as Exhibits 99.1, 99.2, and 99.3, respectively, and are incorporated herein by reference. The foregoing summaries of the terms of the Purchase Agreement, Restricted Warrants, and Lock-Up Agreement are subject to, and qualified in their entirety by, such documents.

On October 10, 2025, the Company issued a press release announcing the Offering. A copy of the press release is attached hereto as Exhibit 99.6 and is incorporated herein by reference. A copy of the legal opinion issued by the Company’s Cayman Islands counsel Campbells is attached hereto as Exhibit 5.1.

Exhibits

Exhibit No.		Description
5.1		Legal Opinion of Campbells
99.1		Form of the Purchase Agreement
99.2		Form of Restricted Warrant
99.3		Form of Lock-Up Agreement
99.4		Press Release

Financial Statements and Exhibits.

Exhibits.

The following exhibits are attached.

Exhibit		Description
99.1		Unaudited Interim Condensed Consolidated Financial Statements as of September 30, 2025, and December 31, 2024, and for the Nine Months Ended September 30, 2025 and 2024
99.2		Operating and Financial Review and Prospects in Connection with the Unaudited Interim Consolidated Financial Statements for the Nine Months Ended September 30, 2025 and 2024
99.3		DiamiR Biosciences Corp.’s Unaudited Interim Condensed Consolidated Financial Statements as of November 30, 2025 and May 31, 2025, and for the Six Months Ended November 30, 2025 and 2024
99.4		DiamiR Biosciences Corp.’s Operating and Financial Review and Prospects in Connection with the Unaudited Interim Consolidated Financial Statements for the Six Months Ended November 30, 2025 and 2024
99.5		Unaudited Pro Forma Condensed Combined Financial Statements
101.INS		Inline XBRL Instance Document
101.SCH		Inline XBRL Taxonomy Extension Schema Document
101.CAL		Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF		Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB		Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE		Inline XBRL Taxonomy Extension Presentation Linkbase Document

SIGNATURES

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, thereunto duly authorized.

	Aptorum Group Limited
Date: October 16, 2025	By:	/s/ Ian Huen
		Name:	Ian Huen
		Title:	CEO

Date: January 21, 2026

2Aptorum Group Limited By: /s/ Ian Huen Ian Huen Chief Executive Officer

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