A combination of Novartis’ cancer meds Tafinlar (dabrafenib) and Mekinist (trametinib) has demonstrated long-term benefit in advanced melanoma patients after five years of treatment.

Results from the Phase III COMBI-AD study, published in The New England Journal of Medicine, shows over half of high-risk patients with resected, stage III BRAF V600-mutated melanoma treated with the combination were alive and relapse-free after five years. This is of particular note given that research suggests most relapses in this patient population occurs within five years.

The detailed results demonstrated that 52% of patients treated with Tafinlar/Mekinist were alive and relapse-free at five years compared to 36% of patients who received placebo. Median relapse-free survival (RFS_ was not reached in the Tafinlar/Mekinist arm, compared to 16.6 months in the placebo arm.

In addition, treatment with Tafinlar/Mekinist reduced the risk of relapse or death by 49% compared to placebo. A further subgroup analysis also showed a generally similar RFS benefit across all substages, with the five-year distant metastasis-free survival (DMFS) rate was 65% in patients treated with Tafinlar/Mekinist compared to 54% of patients receiving placebo.

The trial is still ongoing to assess the secondary endpoint of overall survival (OS), although the first interim analysis showed a three-year OS rate of 86% in the Tafinlar/Mekinist combo arm compared to 77% in the placebo arm. Despite these OS survival results favouring the combination therapy, it did not reach the prespecified interim significance threshold.

“Reaching the five year mark without relapse is a profound moment for a patient living with high-risk, stage III melanoma,” said Jeff Legos, senior vice president, head of Oncology Drug Development at Novartis Oncology.

“Tafinlar plus Mekinist has helped patients and clinicians reimagine what is possible for patients living with advanced melanoma. We are proud of the deep and durable benefit demonstrated in COMBI-AD and remain grateful to the patients, investigators and their families who participated in this clinical trial,” he added.