Company: APM
Filing Date: 2025-12-05
Form Type: 6-K/A
Source: 0001213900-25-118748
Chunk: 2

Company: Aptorum Group Ltd
Filing Date: 2025-12-05
Form: 6-K/A
Chunk 2
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 be established for voting on the proposed
transactions. Shareholders will also be able to obtain copies of the notice, without charge, once available, at the SEC’s website
at www.sec.gov or by directing a request to: 17 Hanover Square, London W1S 1BN, United Kingdom, attention: Ian Huen.

This
Form 6-K shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities
in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under
the securities laws of any such state or jurisdiction. A copy of Aptorum’s registration statement on Form S-4 can be viewed on the
SEC’s website.

Financial Statements and Exhibits.

.

The following exhibits are attached.

| Exhibit |     | Description                                                                                                                 |
| 2.1     |     | Merger Agreement by and between Aptorum and DiamiR, dated July 14, 2025 (1)                                                 |
| 10.1    |     | Management Services Agreement by and between Aptorum Therapeutics and DiamiR, dated July 14, 2025 (1)                       |
| 10.2    |     | Intellectual Property License Agreement by and between Aptorum Therapeutics, DiamiR LLC, and DiamiR, dated July 14, 2025(1) |
| 10.3    |     | Amendment to the Management Services Agreement dated as of December 2, 2025                                                 |

| (1) | Incorporate by reference to the Curent Report on Form 6-K filed on July 22, 2025 |

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SIGNATURES</div>

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.

Date: December 5, 2025

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

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