Multicenter phase 2 basket trial of ipilimumab plus nivolumab for rare tumors: desmoid tumor cohort of DART

The multicenter phase 2 basket trial SWOG S1609 DART evaluates the combination of ipilimumab and nivolumab for rare solid tumors. First results of the desmoid tumor cohort of DART have now been published. The cohort included 16 patients (median age 37 years; up to 5 prior lines of therapy. The objective response rate (primary end point) was 18.8% (3 of 16 patients) while stable disease for at least 6 months was seen in 7 other patients for a clinical benefit rate of 62.5%. The median progression-free survival was 19.4 months, with 6-month PFS rate of 73% and 12-month PFS rate of 67%, while median overall survival was not assessable (13 of 16 patients were alive at the analysis). Grade 3 or 4 adverse events were seen in 50% of patients; there were no grade 5 events. The authors conclude that the combination of ipilimumab and nivolumab was active in patients with desmoid tumors.