Company: APM
Filing Date: 2025-10-14
Form Type: 424B5
Source: 0001213900-25-098635
Chunk: 6

Company: Aptorum Group Ltd
Filing Date: 2025-10-14
Form: 424B5
Chunk 6
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 the forward-looking
statements contained in, or incorporated by reference into, this prospectus supplement. Each forward-looking statement speaks only as
of the date this prospectus supplement or, in the case of documents incorporated by reference, the date of the applicable document (or
any earlier date indicated in the statement), and except as required by law, we undertake no obligation to update publicly any forward-looking
statements, whether as a result of new information, future events or otherwise. We qualify all such forward-looking statements by these
cautionary statements.

<div align='center'>S-iii

PROSPECTUS SUPPLEMENT SUMMARY</div>

The following summary highlights
selected information contained or incorporated by reference in this prospectus supplement. This summary does not contain all of the information
you should consider before investing in the securities. Before making an investment decision, you should read the entire prospectus and
any supplement hereto carefully, including the risk factors section, the financial statements and the notes to the financial statements
incorporated herein by reference, and the documents that we incorporate by reference herein.

Merger with DiamiR Biosciences Corp.

The Company and DiamiR
Biosciences Corp., a Delaware corporation (“DiamiR”), entered into an Agreement and Plan of Merger on July 14, 2025, (the
“Merger Agreement”), pursuant to which, among other matters, we will form a direct, wholly owned subsidiary in the state of
Delaware (“Merger Sub”), which will merge with and into DiamR, with DiamiR surviving as a wholly owned subsidiary of the Company,
and the surviving corporation of the merger with the Merger Sub (the “Merger”). The Company following the Merger is referred
to herein as the “Combined Company.” In addition to the requirement of obtaining Aptorum shareholder approval, the closing of the Merger is subject to the satisfaction or waiver of each of the other closing conditions set forth in the Merger Agreement and therefore, it is possible that the Merger may not occur.

Concurrently with the execution
of the Merger Agreement, DiamiR and Aptorum Therapeutics Limited, a wholly owned subsidiary of the Company (“Aptorum Therapeutics”),
entered into a management services agreement, pursuant to which, Aptorum Therapeutics shall pay a monthly service fee and reimburse expenses
to DiamiR in exchange for the officers and employees of DiamiR providing services to Aptorum Therapeutics to develop a diagnostic test
for early