Sec Form 4 Filing - Knox David R. @ HYPERION DEFI, INC. - 2025-09-29

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Knox David R. 2. Issuer Name and Ticker or Trading Symbol HYPERION DEFI, INC. [ HYPD] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Financial Officer (Last) (First) (Middle) C/O HYPERION DEFI, INC., 23461 SOUTH POINTE DRIVE, SUITE 390 3. Date of Earliest Transaction (MM/DD/YY) 09/29/2025 (Street) LAGUNA HILLS, CA92653 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock, par value $0.0001 09/29/2025 A 100,000 ( 1 ) A $ 0 100,000 D Common Stock, par value $0.0001 09/29/2025 A 200,000 ( 2 ) A $ 0 300,000 D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Knox David R. C/O HYPERION DEFI, INC. 23461 SOUTH POINTE DRIVE, SUITE 390 LAGUNA HILLS, CA92653 Chief Financial Officer Signatures /s/ David R. Knox 10/01/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Represents restricted stock units ("RSUs") that vest as follows: (1) 50,000 RSUs shall vest on March 29, 2026 and (2) 50,000 RSUs shall vest on September 29, 2026, subject to the Grantee's continued employment with the Company through each such vesting date. ( 2 )Represents restricted stock units ("RSUs") that vest as follows: (1) 100,000 RSUs shall vest upon the Company achieving a market capitalization of one hundred fifty million dollars ($150,000,000) and (2) 100,000 RSUs shall vest upon the Company achieving a market capitalization of five hundred million dollars ($500,000,000) (the "Market Cap Milestones"), with the Market Cap Milestones to be considered achieved if the applicable threshold is achieved on ten (10) trading days out of a rolling thirty (30) day period, subject to the Grantee's continued employment with the Company through each such vesting date.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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