X0508 4 2026-01-20 0001783328 TScan Therapeutics, Inc. TCRX 0002018696 Louis Chrystal C/O TSCAN THERAPEUTICS, INC. 830 WINTER STREET WALTHAM MA 02451 false true false false Chief Medical Officer false Stock Option (Right to Buy) 1.12 2026-01-20 4 A false 420000 0.00 A 2036-01-20 Voting Common Stock 420000 420000 D The shares subject to this option shall vest and become exercisable with respect to 25% of the shares on the one-year anniversary of January 20, 2026, with the balance vesting thereafter in equal monthly installments over the next 36 months, subject to the Reporting Person's continued service to the Issuer on each vesting date. /s/ Zoran Zdraveski, Attorney-in-Fact 2026-01-22