Idrx Inc. launched with a $122 million oversubscribed series A round to boost precision drug combinations in cancer, with a first focus on non-PDGFR-driven gastrointestinal stromal tumors (GIST). The Plymouth, Mass.-based firm aims to develop a pairing, potentially with add-ons, powerful enough to handle existing mutations and those that turn up during treatment. Combo therapy attacks “not just the driver mutations, but also the key secondary mutations,” co-founder and CEO Ben Auspitz told BioWorld, and thereby “block every escape route the cancer has.”