Press Release

Sierra Oncology – $29.5 Million Shelf-Takedown

February 23, 2017

San Diego – February 23, 2017 – Cooley advised the underwriters on Sierra Oncology’s $29.5 million shelf-takedown offering of 21,847,636 shares of common stock. The underwriters maintain a 30-day option to purchase up to 577,364 additional shares.

Jefferies acted as sole book-running manager for the offering. Wedbush PacGrow and SunTrust Robinson Humphrey acted as co-managers for the offering.

Sierra Oncology, which trades on The NASDAQ Global Market as “SRRA,” is a clinical-stage drug development company advancing targeted therapeutics for the treatment of patients with cancer.

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