The principal business address of each Reporting Person is 116 Village Boulevard, Suite 200, Princeton, NJ 08540.

The Reporting Person is a Director of the Issuer.

No. During the last five years, the Reporting Person has not been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

No. During the last five years, the Reporting Person has not been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction that resulted in such Reporting Person being subject to a judgment, decree or final order of the type described in Item 2(e).

The Reporting Person is a Citizen of the United States.

No funds or other consideration were used by the Reporting Person to acquire the shares of Common Stock reported herein. Such shares were issued to the Reporting Person solely as non-cash merger consideration in exchange for shares of common stock of DiamiR Biosciences Corp. previously held by the Reporting Person, pursuant to the Agreement and Plan of Merger, dated July 14, 2025, by and among Aptorum Group Limited, DiamiR Biosciences Corp. and the other parties thereto.

The information set forth in Items 3 and 6 is incorporated herein by reference. The shares of Niki Common Stock reported herein were acquired by the Reporting Person solely as merger consideration pursuant to the merger agreement, as described in Item 3 above. No funds or other consideration were expended by the Reporting Person in connection with the receipt of such shares. On July 20, 2026, the merger was consummated pursuant to the merger agreement. In connection with the merger, Aptorum effected the domestication and became a Delaware corporation, changing its name to Niki BioSolutions, Inc. The Niki Common Stock is listed on the Nasdaq Capital Market under the ticker symbol "NIKI" (CUSIP: 653942102). The Reporting Person is a party to that certain Stockholders Agreement, the final form of which is filed as Exhibit 4.5 hereto, which governs certain rights and obligations of the Reporting Person with respect to the Niki Common Stock. Reference is made to the Stockholders Agreement for a complete description of its terms, which are incorporated herein by reference.

As of the date hereof, the Reporting Person beneficially owns 1,515,293 shares of Niki Common Stock, representing approximately 51.56% of the outstanding shares of Niki Common Stock, in each case based on 2,938,625 shares of Niki Common Stock issued and outstanding as of the closing date of the merger. Of such shares, 1,515,016 shares are held directly by the Reporting Person and 277 shares are held in a joint brokerage account at Morgan Stanley in the names of Kira Sheinerman and Felix Sheinerman. The Reporting Person may be deemed to share voting and dispositive power over the 277 shares held in such joint account with Felix Sheinerman.

For each Reporting Person: sole voting power, 1,515,016; shared voting power, 277; sole dispositive power, 1,515,016; and shared dispositive power, 277.

Except for the transactions described in Items 3, 4 and 6 of this Schedule 13D, the Reporting Person has not effected any transaction in the Common Stock during the past 60 days.

Except with respect to 277 shares of Niki Common Stock held in a joint brokerage account at Morgan Stanley in the names of Kira Sheinerman and Felix Sheinerman, no person other than the Reporting Person is known to have the right to receive, or the power to direct the receipt of, dividends from, or proceeds from the sale of, the securities reported herein. Felix Sheinerman, as joint account holder, may be deemed to share such rights with respect to such 277 shares.

Not applicable.

The information set forth in Items 3, 4 and 5 is incorporated herein by reference. The following contracts, arrangements, understandings, or relationships exist among the persons named in Item 2 and between such persons and any other person with respect to any securities of the Company: In connection with the merger, the Reporting Person entered into a Stockholders Agreement with the Issuer. Under the Stockholders Agreement, the Reporting Person may designate two nominees for election to the Issuers board of directors while the Reporting Person collectively owns at least 36% of the Issuer's outstanding Common Stock, and one nominee while such ownership is at least 25%. Each such designation right permanently terminates if the applicable ownership threshold is no longer satisfied. The Reporting Person agreed to vote for such designees and, until the Issuer's 2027 annual meeting, in accordance with the recommendations of the Board's nominating and governance committee with respect to other director nominees. While the Reporting Person beneficially owns at least 25% of the Issuer's outstanding Common Stock, certain significant corporate actions require the prior written consent of the Reporting Person. The Stockholders Agreement also generally restricts transfers of shares subject thereto for six months following its effective date. The foregoing description is qualified in its entirety by reference to the Stockholders Agreement, filed as Exhibit 4.5 hereto and incorporated herein by reference. Except as described above, the Reporting Person is not a party to any contract, arrangement, understanding, or relationship with respect to any securities of the Company, including but not limited to any relating to the transfer or voting of such securities, finder's fees, joint ventures, loan or option arrangements, put or call options, security-based swaps or other derivative securities, guarantees of profits, division of profits or loss, or the giving or withholding of any proxy.

Exhibit 4.5. Stockholders Agreement by and among Aptorum and stockholders of DiamiR (incorporated by reference to Exhibit 4.5 to the Issuer's Registration Statement on Form S-4 (File No. 333-290742)).