REGOSARC: Regorafenib versus placebo in doxorubicin‐refractory soft‐tissue sarcoma—A quality‐adjusted time without symptoms of progression or toxicity analysis

BACKGROUND In a placebo-controlled, randomized phase 2 trial (ClinicalTrials.gov identifier NCT01900743), regorafenib improved progression-free survival (PFS) for patients with doxorubicin-pretreated advanced nonadipocytic sarcoma. A quality-adjusted time without symptoms of progression or toxicity (Q-TWiST) post hoc exploratory analysis was applied to provide an integrated measure of its clinical benefit. METHODS In the base-case analysis, each patient's overall survival (OS) was partitioned into 3 mutually exclusive health states: the time with a grade 3 or 4 adverse event (TOX), the time without symptoms of disease or grade 3 or 4 toxicity from treatment, and the time after tumor progression or relapse. The time spent in each state was weighted with a health-state utility associated with that state and was summed to calculate the Q-TWiST. The stability of the base-case analysis was explored with several sensitivity analyses. RESULTS In nonadipocytic sarcoma, the PFS was (4.0 months [2.6-5.5 months] with regorafenib vs 1.0 month [0.9-1.8 months] with a placebo; hazard ratio, 0.36 [0.25-0.53]; P < .0001); the OS was 13.4 months (8.6-17.3 months) with regorafenib and 9.0 months (6.8-12.5 months) with a placebo (hazard ratio, 0.67 [0.44-1.02]). With the classic definition of TOX (including all grade 3 and 4 clinical adverse events), the Q-TWiSTs were 8.0 months (7.0-9.0 months) with regorafenib and 5.7 months (4.9-6.4 months) with a placebo (P < .001). CONCLUSIONS For patients with doxorubicin-pretreated soft-tissue sarcoma, regorafenib significantly improved quality-adjusted survival in comparison with a placebo. Cancer 2017;123:2294-2302. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.