X0306 4 2022-06-10 0 0001786255 Icosavax, Inc. ICVX 0001813798 Wassil Jim C/O ICOSAVAX, INC. 1930 BOREN AVE., SUITE 1000 SEATTLE WA 98101 1 0 0 0 Common Stock 2022-06-10 4 A 0 11087 0.00 A 11087 D Stock Option (Right to Buy) 6.25 2022-06-10 4 A 0 44556 0.00 A 2032-06-09 Common Stock 44556 44556 D Represents restricted stock units ("RSUs") granted on June 10, 2022. 1/3 of the total number of RSUs granted vest on each of the first three anniversaries of June 10, 2022, the vesting commencement date, subject to the Reporting Person's continuous service on the board of directors of the Issuer through such vesting date. Vesting of the RSUs shall accelerate upon a Change of Control (as defined in the Icosavax, Inc. 2021 Incentive Award Plan). Each RSU represents a contingent right to receive one share of common stock of the Issuer and the RSUs have no expiration date. 1/36th of the total number of shares of common stock subject to the option vest monthly following June 10, 2022, the vesting commencement date, subject to the Reporting Person's continuous service on the board of directors of the Issuer through such vesting date. /s/ Elizabeth Bekiroglu, Attorney-in-Fact 2022-06-14