RA Capital Management led a $130m Series B round in Day One Biopharmaceuticals, a clinical-stage biopharmaceutical company, with participation from Boxer Capital, BVF Partners, Franklin Templeton, Janus Henderson Investors, Perceptive Advisors, T. Rowe Price Associates, Viking Global Investors, Canaan, Access Biotechnology, and Atlas Venture. Proceeds from the Series B financing will allow Day One to accelerate and expand its search and evaluation capabilities, support drug development efforts and continue advancing commercial launch plans for the company’s lead program, DAY101.