Activity of regorafenib in advanced pretreated soft tissue sarcoma

Abstract Background: Regorafenib, a multitargeted tyrosine kinase inhibitor, proved to be active in patients with soft tissue sarcomas (STS). Methods: We conducted an open-label, non-randomized, single-center phase II study in advanced pretreated STS patients. Patients received regorafenib 160 mg daily on days 1 enrule 21 of a 28-day cycle. The primary endpoint was the progression-free survival (PFS) at 8 weeks. Toxicity was registered. Results: Between April 2015 and November 2016, 21 patients were enrolled in the trial. A total of 13 out of 21 evaluable patients (61.9%) were progression-free at 8 weeks. Median PFS was 3.8 months (95% CI: 2.1–9.4). Median overall survival was 14.8 months (95% CI: 7.7–27.8). In the intention-to-treat population, we reported a PFS of 66.7% at 3 months (95% CI: 40.4–83.4) and 16.7% at 12 months (95% CI: 4.1–36.5). As per the RECIST criteria, the response rate was 4.7% (1 partial response out of 21 evaluable patients) with a clinical benefit rate of 61.9%; no complete response was observed. Treatment was well tolerated. Conclusion: Regorafenib shows signs of clinical activity in patients with advanced STS. Clinical Trial Registration: ClinicalTrials.gov NCT02307500.