X0306 4 2021-02-12 0 0001720580 Adicet Bio, Inc. ACET 0001643067 Healey Don C/O ADICET BIO, INC. 500 BOYLSTON STREET, 13TH FLOOR BOSTON MA 02116 0 1 0 0 Chief Technology Officer Stock Option (Right to Buy) 16.82 2021-02-12 4 A 0 30400 0.00 A 2031-02-11 Common Stock 30400 30400 D 25% of the shares shall vest on the first anniversary of the Vesting Start Date and, thereafter, the remainder of the shares shall vest in 36 equal monthly installments, provided that the Reporting Person maintains a service relationship with the Company. /s/ Nick Harvey, Attorney-in-Fact 2021-02-17