Shares of Deciphera Pharmaceuticals Inc. (NASDAQ:DCPH) spiked Tuesday, rising 80% to $35.90 as results of a pivotal phase III study showed its lead candidate, ripretinib, enabled people with fourth-line and beyond gastrointestinal stromal tumors (GIST) to live a median of 6.3 months before disease progression vs. one month with a placebo. Ripretinib also reduced the risk of disease progression or death by 85%.