Regorafenib Improves PFS in Non-apidocytic Soft Tissue Sarcoma

Regorafenib shows clinical antitumor activity and improves progression-free survival (PFS) among patients with non-apidocytic soft tissue sarcoma, according to a study published in The Lancet Oncology.¹

Regorafenib is a multikinase inhibitor approved by the U.S. Food and Drug Administration for the third-line treatment of locally advanced, unresectable or metastatic gastrointestinal stromal tumor (GIST) after progression on imatinib and sunitinib. Because of its proven activity in GIST, researchers evaluated the efficacy and safety of regorafenib among patients with metastatic soft tissue sarcoma who previously received an anthracycline.

For the double-blind, phase 2 REGOSARC trial (ClinicalTrials.gov Identifier: NCT01900743), investigators enrolled 182 adult patients in France and Austria with advanced soft tissue sarcoma, including liposarcoma, leiomyosarcoma, synovial sarcoma, who had previous doxorubicin or other anthracycline treatment. Patients were randomly assigned 1:1 to receive regorafenib for 21 days of each 4-week cycle or placebo.

Median progression-free survival was 1.1 months (95% CI, 0.9-2.3) with regorafenib versus 1.7 months (95% CI, 0.9-1.8) with placebo among patients with liposarcoma (hazard ratio [HR], 0.89; 95% CI, 0.48-1.64; P = .70), suggesting no significant difference between treatment arms in this population cohort.

Among patients with leiomyosarcoma, progression-free survival was 3.7 months (95% CI, 2.5-5.0) with regorafenib compared with 1.8 months (95% CI, 1.0-2.8) with placebo (HR, 0.46; 95% CI, 0.46-0.80; P = .0045).

Similarly, in those with synovial sarcoma, median progression-free survival was 5.6 months (95% CI, 1.4-11.6) versus 1.0 months (95% CI, 0.8-1.4) in the regorafenib and placebo groups, respectively (HR, 0.10; 95% CI, 0.03-0.35; P < .0001).

The most common grade 3 or worse adverse events in the regorafenib arm were arterial hypertension, hand and foot skin reaction, and asthenia. One patient died due to regorafenib-related liver failure.

The findings suggest that further investigation of regorafenib is warranted in patients with leiomyosarcoma and synovial sarcoma.                          

Reference

1. Mir O, Brodowicz T, Italiano A, et al. Safety and efficacy of regorafenib in patients with advanced soft tissue sarcoma (REGOSARC): a randomised, double-blind, placebo-controlled, phase 2 trial. Lancet Oncol. 2016 Oct 14. doi: 10.1016/S1470-2045(16)30507-1 [Epub ahead of print]