The gist: Researchers tested a new melanoma treatment in a clinical trial—a research study with volunteer patients. The treatment combines the targeted drugs vemurafenib and cobimetinib. All of the patients who participated in the trial had melanoma tumors with mutations in the BRAF gene, as detected by molecular testing. The combination treatment proved more beneficial for these patients than vemurafenib alone.
“Combination therapy with both BRAF inhibitor vemurafenib and MEK inhibitor cobimetinib achieves greater progression-free survival and response rates than vemurafenib plus placebo in BRAF-mutation positive melanoma, according to phase III data presented at the ESMO 2014 Congress in Madrid, Spain.
“ ‘Before the results of this study, we knew that cobimetinib plus vemurafenib could be safely delivered together with highly promising rates of tumour shrinkage; however until the performance of a scientifically rigorous randomised trial the potential magnitude of this benefit could not be measured,’ says lead author Dr Grant McArthur, head of the Cancer Therapeutics Program at the Peter MacCallum Cancer Centre, Melbourne, Australia.
“The ongoing CoBRIM study enrolled 495 treatment-naive patients with BRAFV600-mutation-positive unresectable locally advanced or metastatic melanoma. Patients were randomised to received a 28-day treatment cycle of vemurafenib (960 mg, twice daily), and either cobimetinib or placebo (60 mg daily from days 1-21), with a primary end-point of progression-free survival.
“Patients in the combination arm of the study showed a significantly improved median progression-free survival of 9.9 months, compared to 6.2 months in the placebo arm, and a 49% reduction in the risk of progression. Researchers observed a response rate of 68% in the combination arm and 45% in the control arm, including a complete response in 10% of patients treated with combination therapy compared to 4% of patients treated with vemurafenib alone.”