 Shares of Arcus Biosciences Inc. RCUS, -1.10 rocketed 21 in premarket trading Thursday, after Gilead Sciences Inc. GILD, 0.85 said its exercising options to three programs in the companys clinical-stage portfolio for payments of 725 million. The programs in question include anti-TIGIT molecules, domvanalimab and AB308, as well as etrumadenant and quemliclustat, treatments for different cancers. 