Development Overview


Our lead drug candidate, SRA737, is a potent, highly selective, orally bioavailable small molecule inhibitor of Checkpoint kinase 1 (Chk1), a key cell cycle checkpoint and central regulator of the DNA Damage Response (DDR) network.

The oral bioavailability of SRA737 affords greater dosing flexibility for both monotherapy and combination therapy settings than is possible with intravenously administered agents. SRA737 is currently being investigated in two Phase 1 clinical trials in patients with advanced cancer:

Monotherapy РTargeting inhibition of the remaining components of the DDR network with SRA737 may be synthetically lethal to cancer cells and have utility as a monotherapy in a range of tumor indications. In this trial, we plan to exploit synthetic lethality in patients with genetically defined tumors that harbor genomic alterations hypothesized to confer sensitivity to Chk1 inhibition.

Chemotherapy – Chk1 is believed to facilitate tumor cell resistance to chemotherapy or radiation-induced DNA damage. The combination of SRA737 with gemcitabine and gemcitabine/cisplatin may provide synergistic anti-tumor activity, consistent with findings in preclinical oncology models.

Sierra Oncology is also advancing SRA141, a potent, selective and orally bioavailable small molecule inhibitor of the cell division cycle 7 kinase (Cdc7) undergoing preclinical development.