Alternate Dosing Regimen of Regorafenib in Gastrointestinal Stromal Tumors (GISTs)
Regorafenib was approved in 2013 as third-line therapy for advanced GIST at a starting dose of 160 mg daily, 3 weeks on, 1 week off, based on results from the phase 3 GRID study. Researchers at MD Anderson Cancer Center (MDACC) evaluated the activity and safety of regorafenib given continuously at a lower daily dose.
From March 2013 to October 2014, 28 patients with GIST who were treated at MDACC received regorafenib as third- or later-line therapy. Their median age when starting regorafenib was 58 years (range, 21-84 years). Most (79%) patients started with a daily dose of 120 mg regorafenib and took it continuously. Median duration of treatment was 7.3 months.
Median overall survival after initiation of regorafenib was 18 months (95% confidence interval, 7-23 months). Grade 3/4 adverse events (AEs) were noted in 43% of patients receiving modified-dose regorafenib compared with 61% in the GRID study. The most common severe AEs with modified-dose regorafenib were hand-foot syndrome and fatigue (18% each).
Researchers concluded that continuous dosing of regorafenib 120 mg daily compares favorably to the reported efficacy and toxicity associated with standard-dose regorafenib in patients with GIST.
Schvartsman G, et al. CTOS 2016. Abstract 2533131. Poster 7.