X0206 3 2019-05-07 0 0001563880 Trevi Therapeutics, Inc. TRVI 0001607050 O'Shea William J C/O TREVI THERAPEUTICS, INC. 195 CHURCH STREET, 14TH FLOOR NEW HAVEN CT 06510 0 0 1 0 Common Stock 15034 D Series A Preferred Stock Common Stock 43117 D Series C Preferred Stock Common Stock 55902 D The Series A Preferred Stock and the dividends that have accrued thereon to date are convertible on a 9.5-for-one basis into the number of shares of Common Stock shown in Column 3 without payment of further consideration at the holder's election or automatically upon the closing of the Issuer's initial public offering. The number of shares of Common Stock into which the Series A Preferred Stock and accrued dividends thereon are convertible will increase on a daily basis without payment of further consideration as additional dividends accrue. The shares have no expiration date. The Series C Preferred Stock and the dividends that have accrued thereon to date are convertible on a 9.5-for-one basis into the number of shares of Common Stock shown in Column 3 without payment of further consideration at the holder's election or automatically upon the closing of the Issuer's initial public offering. The number of shares of Common Stock into which the Series C Preferred Stock and accrued dividends thereon are convertible will increase on a daily basis without payment of further consideration as additional dividends accrue. The shares have no expiration date. /s/ William J. O'Shea 2019-05-07