X0306 4 2018-06-01 false 0001656328 Sienna Biopharmaceuticals, Inc. SNNA 0001711462 Lizzul Paul F. C/O SIENNA BIOPHARMACEUTICALS, INC. 30699 RUSSELL RANCH ROAD, SUITE 140 WESTLAKE VILLAGE CA 91362 false true false false Chief Medical Officer Common Stock 96434.00 D Common Stock 10557.00 I See Footnote Stock Options (Right to buy) 15.08 2018-06-01 4 A false 48720.00 0.00 A 2028-06-01 Common Stock 48720.00 48720.00 D Includes 1,800 shares of the Issuer's common stock acquired pursuant to the Issuer's Employee Stock Purchase Plan on May 31, 2018. The shares are directly held by the Lizzul Living Trust. Twenty-Five percent (25%) of the shares subject to the option vest and become exercisable on the first anniversary measured from June 1, 2018, and the remaining shares subject to the option vest and become exercisable in 36 successive, equal monthly installments thereafter, subject to the Reporting Person's continued employment or service relationship with the Issuer on each such vesting date. /s/ Timothy K. Andrews, attorney-in-fact for Paul F. Lizzul 2018-06-04