X0306 4 2019-05-14 0 0001505512 Regulus Therapeutics Inc. RGLS 0001762611 Aker Christopher Ray C/O REGULUS THERAPEUTICS INC. 10628 SCIENCE CENTER DR., #100 SAN DIEGO CA 92121 0 1 0 0 Sr. VP & General Counsel Common Stock 2019-05-14 4 A 0 38512 0.00 A 66259 D Common Stock 2019-05-15 4 S 0 6950 1.4095 D 59309 D Stock Option (Right to Buy) 0.95 2019-05-14 4 A 0 7500 0.00 A 2019-05-14 2029-02-04 Common Stock 7500 7500 D On November 11, 2018, the reporting person was granted Restricted Stock Units in the Company's tender offer. The RSUs vest only upon the achievement of a performance-based milestone. The performance criteria were met, resulting in vesting of the RSUs. Upon achievement of the milestone, 50% of the RSU subject to the milestone immediately vest, with the remaining RSUs vesting quarterly in the 24 months following the vesting commencement 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 (RSUs) received by the Reporting Person on 5/14/2019. These sales are made pursuant to an existing 10b5-1 plan under which the Reporting Person has irrevocably elected to satisfy the tax obligations through this sale and do not represent discretionary trades by the Reporting Person. On February 5, 2019, the reporting person was granted an option to purchase the number of shares of common stock set forth in Box 5. The option vests only upon the achievement of a performance-based milestone. The performance criteria were met, resulting in vesting of the option. Upon achievement of the milestone, 50% of the options subject to the milestone immediately vest, with the remaining options vesting in 24 equal monthly installments following the vesting commencement date. Christopher Aker 2019-05-16