Deciphera Pharmaceuticals Inc., of Waltham, Mass., filed form S-1A setting terms for its IPO to raise $100 million by selling 6.25 million shares priced between $15 and $17 per share of common stock. Lead product DCC-2618, in an ongoing phase I trial in patients with advanced malignancies, is designed to inhibit the full spectrum of mutant or amplified KIT and PDGFR-alpha kinases that drive cancers such as gastrointestinal stromal tumors, or GIST.