Mrinal M. Gounder, MD, from the Memorial Sloan Kettering Cancer Center in New York City, and colleagues randomly assigned 87 patients with progressive, symptomatic, or recurrent desmoid tumors to receive sorafenib (400 mg once daily) or matching placebo. Placebo group patients who had disease progression could cross over to the sorafenib group.
The researchers found two-year progression-free survival rates of 81 and 36% in the sorafenib and placebo groups, respectively, at a median follow-up of 27.2 months (hazard ratio for progression or death, 0.13). The objective response rate before crossover was 33 and 20% in the sorafenib and placebo groups, respectively. For patients who had a response, the median time to an objective response was 9.6 and 13.3 months in the sorafenib and placebo groups, respectively; objective responses are ongoing. The most frequently reported adverse events were grade 1 or 2 events of rash, fatigue, hypertension, and diarrhea (73, 67, 55, and 51%, respectively) among patients who received sorafenib.
“Our prospective trial, in which desmoid tumors in patients who were taking placebo were evaluated, provides evidence in support of an initial period of observation in patients with newly diagnosed desmoid tumors, given that 20% of the patients in the placebo group had disease regression,” the authors write.
Bayer, the manufacturer of sorafenib, contributed funding to the study.