Sienna Biopharmaceuticals, Inc.
30699 Russell Ranch Road, Suite 140
Westlake Village, CA 91362
July 24, 2017
VIA EDGAR AND E-MAIL
United States Securities and Exchange Commission
Division of Corporation Finance
100 F Street, N.E.
Washington, D.C. 20549-6010
| Attention: | Suzanne Hayes, Assistant Director | |
| Mary Beth Breslin, Legal Branch Chief | ||
| Johnny Gharib, Senior Counsel | ||
| Sharon Blume, Accounting Branch Chief | ||
| Christine Torney, Senior Staff Accountant | ||
| Re: | Sienna Biopharmaceuticals, Inc. Registration Statement on Form S-1 (Registration No. 333-219142) | |
Ladies and Gentlemen:
In accordance with Rule 461 of Regulation C of the General Rules and Regulations under the Securities Act of 1933, as amended, we hereby request acceleration of the effective date of the Registration Statement on Form S-1 (File No. 333-219142) (the “Registration Statement”) of Sienna Biopharmaceuticals, Inc. (the “Company”). We respectfully request that the Registration Statement become effective as of 4:00 p.m., Washington, D.C. time, on July 26, 2017, or as soon as practicable thereafter. Once the Registration Statement has been declared effective, please orally confirm that event with our counsel, Latham & Watkins LLP, by calling Brian Cuneo at (650) 463-3014.
Thank you for your assistance in this matter.
| Very truly yours, | ||
| SIENNA BIOPHARMACEUTICALS, INC. | ||
| By: | /s/ Frederick C. Beddingfield III | |
| Frederick C. Beddingfield III, M.D., Ph.D. | ||
| President and Chief Executive Officer | ||
| CC: | Richard Peterson, Sienna Biopharmaceuticals, Inc. |
| Timothy Andrews, Sienna Biopharmaceuticals, Inc. |
| Alan C. Mendelson, Latham & Watkins LLP |
| Brian J. Cuneo, Latham & Watkins LLP |
| Alan F. Denenberg, Davis Polk & Wardwell LLP |
