X0306 4 2018-05-01 0 0001638287 Gemphire Therapeutics Inc. GEMP 0001571997 Gullans Steven R. Ph.D. 17199 N. LAUREL PARK DRIVE SUITE 401 LIVONIA MI 48152 1 1 0 0 President & CEO Employee Stock Option (right to buy) 5.56 2018-05-01 4 A 0 150000 0 A 2028-04-30 Common Stock 150000 150000 D The option vests in a series of 48 successive equal monthly installments on the last day of each month, commencing on the grant date. The option includes an early exercise provision, subject to the issuer's right of repurchase with respect to any unvested shares of common stock. The reporting person ceased to be a manager of Excel Venture Fund II, L.P. on May 1, 2018 and will no longer report beneficial ownership of the issuer's securities owned by such entity. /s/ Stephanie Swan, by Power of Attorney 2018-05-03