X0306 4 2019-02-28 0 0001377121 Protagonist Therapeutics, Inc PTGX 0001675878 Shames Richard S. C/O PROTAGONIST THERAPEUTICS, INC. 7707 GATEWAY BOULEVARD, SUITE 140 NEWARK CA 94560 0 1 0 0 Chief Medical Officer Common Stock 2019-02-28 4 A 0 8500 0.00 A 32678 D Common Stock 2019-03-01 4 S 0 657 8.03 D 32021 D Stock Option (right to buy) 8.02 2019-02-28 4 A 0 51000 0.00 A 2029-02-27 Common Stock 51000 51000 D Represents grant of the restricted stock units payable solely in common stock that vest in equal annual installments over four years from the grant date. The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person. The stock option vests in 48 equal monthly installments following the date of grant. /s/ Dinesh V. Patel, Ph.D., Attorney-in-Fact for Richard S. Shames 2019-03-04