- Merck's rock star checkpoint inhibitor Keytruda (pembrolizumab) is currently indicated for secondary treatment of metastatic melanoma after treatment with Yervoy (ipilumumab) and, if a patient is BRAF V600 mutation-positive, a BRAF inhibitor as well. Merck's supplemental biologics license application (BLA) is for primary treamtent of metastatic melanoma and it has now been granted a priority review by the FDA.
- Proposed dosing will be the same for the new indication as for the existing indication: 2 mg/kg every three weeks.
- The submission is based on phase III evidence from a study of 834 patients wtih metastatic melanoma. Results were published in the New England Journal of Medicine on June 25.
This application is part of Merck's ambitious clinical program for Keytruda—a program that involves more than 100 clinical trials across more than 30 tumor types. The evidence base for Merck's submission is based on the results of a randomized, controlled, phase III study that enrolled 834 patients, who were randomized to one of two dosing schedules, or to ipilizumab. Estimated six-month progression-free survival (PFS) survival rates were 47.3% in pembrolizumab-treated patients (based on the standard dosing regimen) and 74.1% at 12 months.
These results are noteworthy given the context in which they occur. Melanoma is a commonly diagnosed cancer. It is estimated that roughly 78,870 people will be diagnosed this year, and 9,940 people wil die from melanoma. The five-year survival rate for metastatic melanoma is roughly 15% to 20%.
A decision on the sBLA expected from the FDA in December.