Phase III trial of Stivarga (Bayer HealthCare) finds positive effect in patients with GIST

A new study demonstrates that Stivarga (regorafenib), from Bayer HealthCare, was able to control GIST for nearly four months longer than placebo in patients for whom Gleevec and Sutent were no longer effective, a result that was highly significant statistically. The Phase III international trial involved 199 treatment-resistant GIST patients at 57 hospitals in 176 countries. Of the 199 patients, 133 received a regorafenib pill daily for three weeks followed by a one-week break, while 66 received a matching placebo. The patients were monitored for at least one year after the trial began.

The study found that tumors objectively grew in less than a month, on average, in GIST patients who were initially randomized to receive a placebo. The study's "cross-over" design made it possible to treat those patients whose tumors grew, and 85 percent of the patients initially on placebo were able to receive regorafenib, which then controlled the disease in these patients as well. Results are published in The Lancet.

A companion report in The Lancet said that the drug had a "modest" benefit in patients with metastatic colon cancer. A commentary by David Cunningham, MD, of the Royal Marsden Hospital in England, said, "In the relatively rare GIST, the case for routine use of this drug in patients following failure of existing treatments is strong." See: "Efficacy and safety of regorafenib for advanced gastrointestinal stromal tumours after failure of imatinib and sunitinib (GRID): an international, multicentre, randomised, placebo-controlled, phase 3 trial." Prof George D Demetri et al. The Lancet, Early Online Publication, 22 November 2012 DOI: /10.1016/S0140-6736(12)61857-1