On 27 June 2018, the US Food and Drug Administration (FDA) approved encorafenib and binimetinib (BRAFTOVI and MEKTOVI, Array BioPharma Inc.) in combination for patients with unresectable or metastatic melanoma with a BRAF V600E or V600K mutation, as detected by an FDA-approved test.
Approval was based on a randomised, active-controlled, open-label, multicentre trial (COLUMBUS; NCT01909453) in 577 patients with BRAF V600E or V600K mutation-positive unresectable or metastatic melanoma. Patients were randomised (1:1:1) to receive binimetinib 45 mg twice daily plus encorafenib 450 mg once daily, encorafenib 300 mg once daily, or vemurafenib 960 mg twice daily. Treatment continued until disease progression or unacceptable toxicity.
The major efficacy measure was progression-free survival (PFS) using RECIST v1.1 response criteria and assessed by blinded independent central review. The median PFS was 14.9 months for patients receiving binimetinib plus encorafenib, and 7.3 months for the vemurafenib monotherapy arm (hazard ratio 0.54, 95% CI: 0.41, 0.71, p < 0.0001).
Overall response rates assessed by central review were 63% and 40%, respectively.
Median response duration was 16.6 months vs. 12.3 months, respectively.
The most common (≥ 25%) adverse reactions in patients receiving the combination were fatigue, nausea, diarrhoea, vomiting, abdominal pain, and arthralgia. Discontinuation of therapy due to adverse reactions occurred in 5% of patients receiving the combination; the most common reasons were haemorrhage and headache.
FDA also granted approval of the THxID BRAF Kit (bioMérieux) as a companion diagnostic for these therapeutics.
The recommended doses for binimetinib is 45 mg orally twice daily and for encorafenib 450 mg orally once daily.
Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System.