0001290149 2022-01-21 2022-01-21 false 0001290149 8-K 2022-01-21 SIERRA ONCOLOGY, INC. DE 001-37490 20-0138994 1820 Gateway Drive San Mateo CA 94404 (605) 376-8679 false false false false Common Stock, $0.001 par value SRRA NASDAQ false