13D Filing: Phase4 Partners Ltd and Albireo Pharma Inc. (ALBO)

Represents shares held by Phase4 Ventures III GP LP (“Phase4 GPLP”) in its capacity as general partner of Phase4 Ventures III LP (“Phase4 III”). Phase4 GPLP is the general partner of Phase4 III. The general partner of Phase4 GPLP is Phase4 Ventures III General Partner Limited (“Phase4 GP”). Phase4 GP has appointed Phase4 Partners Limited (“Phase4 Partners”) to act as the manager of Phase4 III. Phase4 Partners ultimately exercises voting and investment power over the securities held by Phase4 GPLP. Dr. Alastair McKinnon, Denise Scots-Knight, Ph.D. and Charles Sermon are Directors of Phase4 Partners. Phase4 Partners, Phase4 GP, Phase4 GPLP and Phase4 III may each be deemed to have sole voting and dispositive power over the shares and Dr. McKinnon, Dr. Scots-Knight and Mr. Sermon may each be deemed to have shared voting and dispositive power over the shares.

The percentage ownership was calculated based on 11,148,285 shares of common stock outstanding as of the completion of the offering disclosed in the Prospectus Supplement to the Registration Statement on Form S-3 (File No. 333-220958) filed by Albireo Pharma, Inc. (the “Issuer”) with the Securities and Exchange Commission on January 25, 2018, and the disclosure by the Issuer of the successful completion of this offering in a press release dated January 29, 2018.