Expanding on a proven class of anti-cancer drugs

We are initiating coverage on Sierra Oncology, a drug developer targeting the DNA damage response (DDR) network to treat cancer. The company has two Phase I trials with SRA737 targeting checkpoint kinase 1 (Chk1) in patients with genetic tumor types expected to respond to the drug. Inhibition of Chk1 is lethal in cells with defective p53 (among others), one of the most common cancer mutations, and also enhances the response to chemotherapy. Sierra also has the cell division cycle 7 (Cdc7) inhibitor SRA141 in preclinical testing. Our initial valuation is $206m or $3.95/share.