X0206 3 2020-02-27 0 0001787297 Passage BIO, Inc. PASG 0001365617 Heron Patrick J 601 UNION STREET SEATTLE WA 98101 1 0 1 0 Series A-1 Preferred Stock Common Stock 2977242 I By Frazier Life Sciences IX, L.P. Series A-2 Preferred Stock Common Stock 1049175 I By Frazier Life Sciences IX, L.P. Series B Preferred Stock Common Stock 432802 I By Frazier Life Sciences IX, L.P. Each share of the issuer's Series A-1 Preferred Stock will automatically convert into one (1) share of the issuer's Common Stock immediately upon the closing of the issuer's initial public offering ("IPO") and has no expiration date. These securities are held of record by Frazier Life Sciences IX, L.P. ("Frazier Life Sciences"), of which FHMLS IX, L.P. ("FHMLS L.P.") is the general partner. FHMLS IX, L.L.C. ("FHMLS LLC") is the general partner of FHMLS L.P. The reporting person, and James N. Topper are the managing members of FHMLS LLC and may be deemed to have shared voting and dispositive power over the shares held by Frazier Life Sciences. The reporting person disclaims beneficial ownership over such securities except to the extent of his pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purposes. Each share of the issuer's Series A-2 Preferred Stock will automatically convert into one (1) share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date. Each share of the issuer's Series B Preferred Stock will automatically convert into one (1) share of the issuer's Common Stock immediately upon the closing of the issuer's IPO and has no expiration date. /s/ Richard Morris as attorney-in-fact for Patrick J. Heron 2020-02-27