X0306 4 2018-05-29 0 0001377121 Protagonist Therapeutics, Inc PTGX 0001135139 KHOSLA CHAITAN PHD C/O PROTAGONIST THERAPEUTICS, INC. 7707 GATEWAY BLVD., SUITE 140 NEWARK CA 94560 1 0 0 0 Stock Option (right to buy) 6.98 2018-05-29 4 A 0 12000 0.00 A 2028-05-28 Common Stock 12000 12000 D The shares subject to this option shall vest at the earlier on (i) May 29, 2019, or (ii) the date of the 2019 Annual Meeting of stockholders of the Issuer, subject to the non-employee director's continuous service with the Issuer through such dates. The shares subject to this option will vest in full upon completion of a Change in Control (as defined in the Issuer's 2016 Equity Incentive Plan). /s/ Thomas P. O'Neil, Attorney-in-Fact 2018-06-12