Topline results from the pivotal phase III INVICTUS trial showed that the novel drug ripretinib improved progression-free survival (PFS; primary endpoint) compared with placebo in patients with gastrointestinal stromal tumors (GIST), according to a press release from the drug’s manufacturer, Deciphera Pharmaceuticals Inc.
The randomized, placebo-controlled, double-blind, international, multicenter study included 129 patients with advanced GIST who previously received treatment, including at least imatinib, sunitinib, and regorafenib. Patients were randomized 2:1 to receive ripretinib 150 mg or placebo once daily.
Improved survival with ripretinib
The median PFS was 6.3 months (27.6 weeks) with ripretinib compared with 1.0 month (4.1 weeks) in the placebo group, resulting in an 85% reduced risk of disease progression or death with ripretinib (hazard ratio [HR] = 0.15; P<0.0001).
Ripretinib resulted in an overall response rate of 9.4% compared with 0% for placebo, although this was not statistically significant (P=0.0504). The median overall survival was 15.1 months with ripretinib and 6.6 months with placebo (HR=0.36; P=0.0004).
Grade 3 or 4 treatment-related adverse events (AEs) occurred in 42 patients (49%) receiving ripretinib and 19 (44%) receiving placebo. Common grade 3/4 AEs in the ripretinib cohort included anemia (9%; n=8), abdominal pain (7%; n=6), and hypertension (7%; n=6), while the placebo cohort experienced anemia (14%; n=6).
The company said it “expects to submit a New Drug Application to the U.S. Food and Drug Administration for ripretinib for the treatment of patients with advanced GIST who have received prior treatment with imatinib, sunitinib, and regorafenib in the first quarter of 2020.”