X0306 4 2020-08-01 0 0001463361 Unity Biotechnology, Inc. UBX 0001727640 Sullivan Lynne Marie C/O UNITY BIOTECHNOLOGY, INC. 285 EAST GRAND AVENUE SOUTH SAN FRANCISCO CA 94080 0 1 0 0 See Remarks Stock Option (Right to Buy) 9.96 2020-08-01 4 A 0 240000 0.00 A 2030-07-31 Common Stock 240000 240000 D The underlying shares vest and become exercisable pursuant to the following schedule: Twenty Five Percent (25%) of the shares subject to the option vested on August 1, 2021 (the "Vesting Commencement Date"), and the remaining shares subject to the option vest in 36 successive, equal monthly installments thereafter on each monthly anniversary of the Vesting Commencement Date, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date. Interim Chief Financial Officer /s/ Tamara L. Tompkins, Attorney-in-Fact for Lynne Sullivan 2020-08-04