Drug Combination Leads to Progression-Free Survival in Patients With Cancer

A randomized clinical trial has found strong evidence that a combination of 2 targeted melanoma drugs leads to longer progression-free survival compared with intermittent treatment for patients with cancer. The study results were presented at the 2020 virtual annual meeting of the American Association for Cancer Research.

The study, known as SWOG S1320, focuses on treatment for melanomas with mutations in the BRAF gene, changes that cause cancer cells to grow rapidly. Approximately half of all melanomas diagnosed involve a BRAF mutation, and the study focused on treatments for patients with the most common melanoma mutations BRAFV600E and BRAFV600K. These cancers can be difficult to treat because they often become resistant to drugs designed to target BRAF mutations and can return months after treatment even more difficult to defeat.

The study is part of the National Cancer Institute’s National Clinical Trials Network (NCTN), including more than 2000 cancer centers, university hospitals, and community sites in the United States and abroad. Using the network, researchers enrolled 249 eligible patients with melanoma from 68 clinical sites over a 5-year period. Of the 249 patients, 206 were randomized. Every patient was given the commonly prescribed BRAF and MEK inhibitor combination regimen, dabrafenib and trametinib.

One group of patients took the combination of pills each day until their cancer progressed. Another group took the same daily combination for 5 weeks, then took a 3-week break, then resumed treatment for another 5 weeks, then took a break until their cancer progressed.

Patients who received continuous drug doses, on average, did not have their cancer progress for 9 months. Patients who received intermittent doses, on average, did not have their cancer progress for 5 months.

The researchers hypothesize that the tissue and blood samples taken during the trial may hold clues and can be used for further study. Although measuring overall survival was not the primary research objective of the trial, regardless of those dosing schedule, patients with melanoma on the trial have lived about the same amount of time. Approximately half of the patients who participated in the trial have died over the course of the study, which continues to follow those who are still alive.

Reference

• Continuous dosing improves progression-free survival for melanoma patients with common mutations [press release]. Eurek Alert website. Published April 27, 2020. https://www.eurekalert.org/pub_releases/2020-04/s-cdi042420.php. Accessed April 28, 2020.