Phase II prospective study with sorafenib in advanced soft tissue sarcomas after anthracycline-based therapy

We investigated the activity and safety of sorafenib, a multitargeted tyrosine-kinase inhibitor, in patients with advanced soft tissue sarcomas (STS). An open-label nonrandomised multicentre phase II study was conducted in advanced STS patients pre-treated with anthracycline-based chemotherapy. Patients received sorafenib 400 mg twice daily for 28 days. The primary end point was the progression-free survival (PFS) rate at 6 months. Toxicity was assessed. Clinical outcomes were evaluated in all histologies and in leiomyosarcoma (L) and angiovascular sarcomas (A). Between November 2006 and January 2010, 101 patients (36 L, 19 A, and 46 others) were enrolled; 76 patients per-protocol (PP) and 100 per intention-to-treat (ITT) were assessable for the primary end point. In the PP analysis, 11 (14.5%) achieved partial response and 25 (32.9%) stable disease; 6-month PFS rates were all histologies, 34.5%; L, 38.4%; and A, 56.3%. In the ITT analysis, 6-month PFS results were 27.1, 35, and 35.5% in all histologies, L, and A, respectively. When stratified by histology, we observed a better PFS favouring leiomyosarcoma versus other histologies (P = 0.033). Treatment was well tolerated. Sorafenib appears to be a promising option in leiomyosarcoma patients. This finding warrants further evaluation in histology-driven trials.