X0306 4 2022-02-24 0 0001661998 Homology Medicines, Inc. FIXX 0001754067 Kelly Timothy P C/O HOMOLOGY MEDICINES, INC. ONE PATRIOTS PARK BEDFORD MA 01730 0 1 0 0 Chief Operating Officer Employee Stock Option (Right to Buy) 2.71 2022-02-24 4 A 0 28200 0.00 A 2032-02-24 Common Stock 28200 28200 D Restricted Stock Units 2022-02-24 4 A 0 4800 0.00 A Common Stock 4800 4800 D The option vests in 48 substantially equal monthly installments on the first day of each calendar month following January 1, 2022. Each restricted stock unit represents a contingent right to receive one share of Issuer common stock. The restricted stock units have no expiration date. The restricted stock units will vest and settle as to one third of the restricted stock units on each of the first three anniversaries of January 1, 2022 so that such RSUs will become fully vested on January 1, 2025. /s/ W. Bradford Smith, Attorney-in-Fact for Timothy P. Kelly 2022-02-28