Key clinical point: Regorafenib warrants further clinical investigation in refractory non-adipocytic sarcomas, based on an updated analysis of the patients who crossed over from placebo to active drug in the placebo-controlled, phase-2 REGOSARC trial.

Main finding: The progression-free survival (PFS) benefit of regorafenib as compared to placebo was confirmed with longer follow-up (HR = 0.50; 95% CI: 0.35–0.71; P less than .0001). Overall survival was not significantly different (HR = 0.78; 0.54–1.12; P = .18); however, 55 of 68 patients who progressed on placebo (81%) received cross-over regorafenib after progression and 59% of them had a growth modulation index of at least 1.3 (95% CI, 45–71%). Delayed start of regorafenib was associated with a statistically non-significant shorter PFS as compared to early treatment (HR = 1.21; 0.84–1.73; P = .30) without impact on overall survival.

Study details: From June 2013 to December 2014, 139 patients were enrolled in the non-adipocytic sarcoma cohorts. Median follow-up is now 32.4 months. In the placebo arm, intra-patient benefit of regorafenib after cross-over was evaluated by the growth modulation index (PFS after cross-over regorafenib divided by PFS with placebo). The activity of delayed (after cross-over) vs. early (at study entry) regorafenib was evaluated by comparing PFS after cross-over to regorafenib to PFS after randomisation in the regorafenib arm.

Disclosures: The study was supported by Bayer HealthCare. The authors declared no relevant financial conflicts of interest.

Source: Brodowicz T et al. European Journal of Cancer 2018: 99; 28-36. https://doi.org/10.1016/j.ejca.2018.05.008