Phase 2 Study of Regorafenib in Patients with Metastatic STS (RESOUND)
Angiogenesis plays a key role in the biology of sarcoma, particularly leiomyosarcoma (LMS), synovial sarcoma (SS), and vascular sarcoma (VS). Regorafenib is indicated for use in gastrointestinal stromal tumors after imatinib and sunitinib have failed.
RESOUND is a single-stage, phase 2 trial of regorafenib in patients with metastatic cancer, including LMS, SS, and VS, which is refractory to standard treatments. Patients received oral regorafenib 160 mg once daily for 3 weeks on, 1 week off until disease progression or unacceptable toxicity. Response was assessed by computed tomography scan every 8 weeks per RECIST 1.1. The primary end point was progression-free rate at 2 months.
From April 2015 to June 2016, 15 patients with soft-tissue sarcomas (11 LMS, 3 SS, 1 VS) enrolled. Their median age was 61 years. They received a median of 4 previous regimens.
Twelve of the 15 patients were evaluable for the primary end point at 8 weeks: 9 patients achieved stable disease, while the other 3 progressed. The 2-month progression-free rate was 75%. After median follow-up of 5.8 months, median progression-free survival and overall survival were not reached.
The most common drug-related grade 3 adverse events were hypertension (26%), fatigue (13%), and rash/desquamation (6%).
Regorafenib is well-tolerated and appears to be effective in metastatic, pretreated LMS, SS, and VS.
- De Sanctis R, et al. CTOS 2016. Abstract 2570512. P2 Poster 120.