X0306 4 2021-02-05 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 See Remarks Employee Stock Option (Right to Buy) 13.78 2021-02-05 4 A 0 65000 0.00 A 2031-02-05 Common Stock 65000 65000 D Restricted Stock Units 2021-02-05 4 A 0 11000 0.00 A Common Stock 11000 11000 D The option vests in 48 equal monthly installments on the first day of each calendar month following January 1, 2021. Each restricted stock unit represents a contingent right to receive one share of Issuer common stock. 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, 2021 so that such RSUs will become fully vested on January 1, 2024. Chief Technical Operations Officer /s/ Bradford Smith, Attorney-in-Fact for Timothy P. Kelly 2021-02-09