Multinational phase 3 trial of continuous nirogacestat treatment in adults with desmoid tumors: long-term results from DeFi

The placebo-controlled multinational phase 3 DeFi trial evaluated the oral γ-secretase inhibitor nirogacestat for progressive desmoid tumors in adult patients. Long-term results of the trial have now been published. The median duration of exposure was 33.6 months (range 0.3-61.8). Median progression-free survival was not reached.The objective response rate with up to 4 years of nirogacestat treatment was 45.7%. Further target tumor size reduction occurred in most patients. Benefits in PROs were sustained while on treatment. Frequently reported treatment-emergent adverse events decreased in incidence and severity over time.