Sumary of Combination of two targeted drugs shows “clinically meaningful” activity in some malignant brain tumors:
- A combination of two targeted cancer drugs showed unprecedented, “clinically meaningful” activity in patients with highly malignant brain tumors that carried a rare genetic mutation, according to a clinical trial report by investigators from Dana-Farber Cancer Institute.
- The drug combination, which blocked an overactive cell-growth signaling pathway, shrank tumors by 50% or more in one-third of 45 patients with hard-to-treat high-grade gliomas, including glioblastomas, the most aggressive brain tumor.
- This mutation is found in only two to three percent of patients with high-grade gliomas but is found in up to 60% of certain types of low-grade gliomas.
- “This is the first time that any targeted drug has been shown to work in glioblastoma in a clinical trial,” said Patrick Wen, MD, first author of the report in The Lancet Oncology and director of the Center for Neuro-Oncology at Dana-Farber.
- The two drugs paired in the study were dabrafenib and trametinib.
- Both drugs target proteins in the MAPK pathway, a signaling chain of proteins that acts as a switch for cell growth and can become stuck in the “on” position, causing uncontrolled growth leading to tumors.
- The patients were not cured, but those who responded to the drugs experienced remarkably durable benefits – by one assessment, the median duration of response was 13.6 months, and by another assessment, it was 36.9 months.
- The findings are from an ongoing phase 2 study called ROAR (Rare Oncology Agnostic Research) that has been enrolling patients since 2014 in 27 community and academic cancer centers in 13 countries.