Sierra Oncology Inc. announced that it has successfully transferred sponsorship of the two ongoing Phase 1 clinical trials evaluating its Checkpoint kinase 1 (Chk1) inhibitor, SRA737, from the Cancer Research UK Centre for Drug Development to the company. In accordance with the license agreement for SRA737, a $2.0 million fee is due to CRT Pioneer Fund LP for the achievement of this milestone. SRA737 targets Chk1, a key cell cycle checkpoint and central regulator of the DDR network, an exciting emerging target in oncology that has broad clinical and commercial potential.