X0306 4 2021-03-15 0 0001787297 Passage BIO, Inc. PASG 0001799779 Romano Gary TWO COMMERCE SQUARE 2001 MARKET STREET, 28TH FLOOR PHILADELPHIA PA 19103 0 1 0 0 Chief Medical Officer Common Stock 2021-03-15 4 M 0 10000 8.07 A 10000 D Common Stock 2021-03-15 4 S 0 8383 20.9546 D 1617 D Common Stock 2021-03-15 4 S 0 1617 21.8616 D 0 D Employee Stock Option (right to buy) 8.07 2021-03-15 4 M 0 10000 0.00 D 2029-10-23 Common Stock 10000 300821 D The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $20.60 to $21.51, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $21.65 to $22.10, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein. The option vests as to 25% of the total shares on August 20, 2020 and then 2.0833% of the total shares vest monthly thereafter, with 100% of the total shares vested on August 20, 2023 subject to the reporting person's provision of service to the issuer on each vesting date. The option provides for an early-exercise provision and is exercisable as to unvested shares, subject to the issuer's right of repurchase. /s/ Edgar Cale, Attorney-in-Fact 2021-03-17