Acrivon Therapeutics Inc.’s $130 million financing disclosed April 9 hiked confidence in then-pending data with ACR-368 (prexasertib), the selective small-molecule inhibitor that targets checkpoint kinase 1 (CHK1) and CHK2. Undergoing tests in a potentially registrational phase II trial across multiple tumor types, ACR-368 also raised the stakes for Boundless Bio Inc., which is developing CHK1 inhibitor BBI-355.