Experimental agent slows progression of colorectal cancer
The investigational drug regorafenib (BAY 73-4506) conferred a statistically significant benefit in overall and progression-free survival in patients with metastatic colorectal cancer (mCRC) in whom no approved standard therapy was effective.
Regorafenib is an oral multikinase inhibitor of a broad range of angiogenic, oncogenic, and stromal kinases. Its safety and effectiveness were evaluated in the international phase 3 CORRECT trial, involving 760 patients with mCRC who had progressed after all approved standard therapies. Preliminary findings were presented by US principal investigator and Mayo Clinic oncologist Axel Grothey, MD, at the Gastrointestinal Cancers Symposium of the American Society of Clinical Oncology, held January 19-21 in San Francisco, California (www.asco.org/ASCOv2/Meetings/Abstracts?&vmview=abst_detail_view&confID=115&abstractID=87795).
A total of 505 study participants had been randomized to receive regorafenib plus best supportive care (BSC), with the remaining 255 assigned to placebo plus BSC. The regorafenib group exhibited a 29% increase in overall survival compared with those treated with placebo. The difference in median length of overall survival was also statistically significant: 6.5 months with regorafenib vs 5.0 months with placebo. Median progression-free survival was 1.9 months for regorafenib and 1.7 months for placebo. The most frequent grade 3+ adverse events in the regorafenib arm were hand-foot skin reaction (17%), fatigue (15%), diarrhea (8%), hyperbilirubinemia (8%), and hypertension (7%).
Overall, regorafenib use reduced risk of death from colorectal cancer during the trial by 23%. The study was changed to unblinded status so that placebo users could be put on regoranefib.
“Patients with metastatic colorectal cancer who have failed all approved and standard therapies have a poor prognosis,” acknowledged Grothey in a statement describing his group's findings. “This is the first and only agent in this setting that has demonstrated statistically significant overall survival benefit.”