X0306 4/A 2020-07-23 2020-07-24 0 0001808865 iTeos Therapeutics, Inc. ITOS 0001816206 Van Hauwermeiren Timothy C/O ITEOS THERAPEUTICS, INC. 139 MAIN STREET CAMBRIDGE MA 02142 1 0 0 0 Stock Option (Right to Buy) 19.00 2020-07-23 4 A 0 16608 0.00 A 2030-07-23 Common Stock 16608 0 D This amendment is being filed solely for the purpose of correcting the vesting schedule, as follows: this stock option shall vest on the earlier of (i) the first anniversary of the grant date or (ii) the Company's next annual meeting of stockholders following the grant date, subject to continued service through the applicable vesting date. /s/ Michel Detheux, as Attorney-in-Fact 2020-10-21