X0306 4 2019-05-09 1 0001563880 Trevi Therapeutics, Inc. TRVI 0001774956 Mellon Family Investment Co V C/O TREVI THERAPEUTICS, INC. 195 CHURCH STREET, 14TH FLOOR NEW HAVEN CT 06510 0 0 1 0 0001775165 MFIC V, LLC C/O TREVI THERAPEUTICS, INC. 195 CHURCH STREET, 14TH FLOOR NEW HAVEN CT 06510 0 0 1 0 Common Stock 2019-05-09 4 C 0 222816 A 222816 D Common Stock 2019-05-09 4 J 0 24340 0.00 A 247156 D Common Stock 2019-05-09 4 P 0 100000 10.00 A 347156 D Series C Preferred Stock 2019-05-09 4 C 0 1908450 0.00 D Common Stock 222816 0 D On May 9, 2019, the Series C Preferred Stock, and the dividends that had accrued thereon to date, converted into Common Stock on a 9.5-for-one basis without payment of further consideration automatically upon the closing of the Issuer's initial public offering. The shares had no expiration date. MFIC V, LLC, the general partner of Mellon Family Investment Company V, has sole voting and investment control with respect to shares of the Issuer's Common Stock held by Mellon Family Investment Company V. Consists of shares transferred to Mellon Family Investment Company V by TPG Biotechnology Partners III, L.P. in connection with the closing of the Issuer's initial public offering. By: Mellon Family Investment Company V, By: its General Partner, MFIC V, LLC, /s/ Douglas L. Sisson, Member 2019-05-09 By: MFIC V, LLC, /s/ Douglas L. Sisson, Member 2019-05-09