Sierra Oncology is a late-stage biopharmaceutical company on a quest to deliver targeted therapies that treat rare forms of cancer. We harness our deep scientific expertise to identify compounds that target the root cause of disease to advance targeted therapies with assets on the leading edge of cancer biology. Our team takes an evidence-based approach to understand the limitations of current treatments and explore new ways to change the cancer treatment paradigm. Together we are transforming promise into patient impact. Our lead product candidate, momelotinib, is a selective and orally bioavailable JAK1, JAK2 and ACVR1 inhibitor currently under investigation for the treatment of myelofibrosis. Myelofibrosis results from dysregulated JAK-STAT signaling and is characterized by constitutional symptoms, splenomegaly (enlarged spleen) and progressive anemia. Momelotinib is currently under investigation in the MOMENTUM clinical trial, a global, randomized, double-blind Phase 3 study for symptomatic and anemic myelofibrosis patients. Top-line data are anticipated in H1 2022. The U.S. Food & Drug Administration has granted Fast Track designation for momelotinib. Our pipeline also consists of SRA737, a potent, highly selective, orally bioavailable small molecule inhibitor of Checkpoint kinase 1 (Chk1). Promising clinical activity has been observed with SRA737 in combination with low-dose gemcitabine (LDG). Additionally, SRA737 and LDG strongly synergizes with anti-PD(L)1 preclinically, enabling further promising clinical development opportunities. For more information, please visit www.SierraOncology.com.