GlaxoSmithKline plc (GSK) has withdrawn its Marketing Authorisation Application (MAA) to the European Medicines Agency (EMA) for the use of Mekinist (trametinib) in combination with the previously approved BRAF inhibitor Tafinlar (dabrafenib) for the treatment of adult patients with unresectable or metastatic melanoma with a BRAF V600 mutation.

The application for the use of Mekinist as a single agent in the same patient population, submitted simultaneously with the MAA for the combination, is still undergoing review by the EMA.

The Committee for Medicinal Products for Human Use (CHMP) of the EMA has indicated that the data provided to date by GSK did not allow the Committee to conclude on a positive benefit-risk balance of the combination. GSK intends to re-submit the MAA for the combined use of Tafinlar and Mekinist when additional data from the ongoing phase III programme become available.

The regulatory submission for the combination was based on the results from an open-label randomised three-arm phase II study, provided to EMA in 2012. The study aimed to assess the safety and efficacy of dabrafenib in combination with two different doses of trametinib compared to dabrafenib monotherapy in patients with unresectable or metastatic BRAF V600 E or K mutation-positive melanoma.

Additional data from the randomised, double-blind phase III study (COMBI-d) comparing the combination of dabrafenib and trametinib to dabrafenib and placebo as first-line therapy in the same patient population were also provided to EMA earlier this year.

Dr Rafael Amado, head of oncology R&D at GSK, said “Although we have withdrawn our application, we remain committed to providing further data from our ongoing phase III development programme to support a subsequent re-submission in Europe.

“While significant progress has been made in treating metastatic melanoma over the last few years, we believe more treatment options are needed, and we will work with the European regulators towards making the combination available for patients.”

Mekinist is approved as a single agent and in combination with Tafinlar in the US and Australia. Mekinist is also approved as monotherapy in Canada.

Mekinist was in-licensed by GSK in 2006. GSK holds the worldwide exclusive rights to develop, manufacture and commercialise Mekinist, while Japan Tobacco retains co-promotion rights in Japan.