Sec Form 4 Filing - MCDADE MARK @ Icosavax, Inc. - 2022-06-10

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

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person MCDADE MARK 2. Issuer Name and Ticker or Trading Symbol Icosavax, Inc. [ ICVX] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O QIMING U.S. VENTURES MANAGEMENT, LLC, 11100 NE 8TH STREET, SUITE 200 3. Date of Earliest Transaction (MM/DD/YY) 06/10/2022 (Street) BELLEVUE, WA98004 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 06/10/2022 A 5,543( 1 ) A $ 0 55,786 D Common Stock 3,510,228 I By Qiming U.S. Healthcare Fund II, L.P.( 2 )

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 Stock Option (Right to Buy) $ 6.25 06/10/2022 A 22,278 ( 3 ) 06/09/2032 Common Stock 22,278 $ 0 22,278 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other MCDADE MARK C/O QIMING U.S. VENTURES MANAGEMENT, LLC 11100 NE 8TH STREET, SUITE 200 BELLEVUE, WA98004 X Signatures /s/ Mark McDade 06/14/2022 Signature of Reporting Person Date

Explanation of Responses:

( 1 )These shares represent a restricted stock unit ("RSU") award, which shall vest at the earlier of (x) June 10, 2023 or (y) the date of the 2023 Annual Meeting of Stockholders. The vesting of the RSUs is subject to the Reporting Person's continuous service through such vesting date. ( 2 )The securities are directly held by Qiming U.S. Healthcare Fund II, L.P. ("Qiming"). Qiming U.S. Healthcare GP II, LLC ("Qiming GP") is the sole general partner of Qiming. The Reporting Person is a managing member of Qiming GP and may be deemed to share voting and dispositive power over the shares held by Qiming. The Reporting Person disclaims beneficial ownership of the reported securities, except to the extent of his pecuniary interest therein. ( 3 )This option vests in substantially equal monthly installments over a twelve-month period commencing on July 10, 2022 (or, in the event the 2023 Annual Meeting of Stockholders occurs prior to June 10, 2023, any remaining unvested portion of the option will vest on the date of the 2023 Annual Meeting of Stockholders), subject to the Reporting Person's continuous service as of the applicable 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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.