PEMBROLIZUMAB BETTER THAN IPILIMUMAB FOR MELANOMA-KEYNOTE-006 HALTED

Pembrolizumab (Keytruda, Merck) has bested ipilimumab (Yervoy, Bristol-Myers Squibb) in the treatment of advanced melanoma in a head-to-head clinical trial, according to an announcement today from Merck.

Pembrolizumab demonstrated a statistically significant and "clinically meaningful" improvement in overall and progression-free survival, compared with ipilimumab, the company reports.

The randomized phase 3 study, known as KEYNOTE-006, will be stopped early on the recommendation of an independent Data Monitoring Committee.

The complete data will be presented in the opening plenary session at the American Association of Cancer Research annual meeting in April.

Ipilimumab is currently the standard of care in the first-line treatment of advanced melanoma.

Pembrolizumab is already approved for use in patients with advanced or unresectable melanoma who are no longer responding to other drugs, including ipilimumab and BRAF inhibitors (in patients whose tumors express BRAF V600). This indication received accelerated approval on the basis of tumor response rate and durability of response.

The new clinical trial pitted two different monoclonal antibody treatment strategies against one another; the programmed death (PD) inhibitor pembrolizumab was compared with the cytotoxic T-lymphocyte antigen 4 (CTLA-4)-blocking antibody ipilimumab.

Pembrolizumab is now the first anti-PD-1 therapy to demonstrate a survival advantage over the standard of care for the first-line treatment of advanced melanoma, according to Merck.

"Evidence from our clinical program for pembrolizumab will help to define the appropriate treatment of advanced melanoma," Roger Perlmutter, MD, PhD, president of Merck Research Laboratories, said in a press statement.

KEYNOTE-006 is a global open-label study of patients with unresectable stage III or IV advanced melanoma who have received no more than one previous systemic therapy.

In the three-group study, 834 patients were randomized to receive pembrolizumab 10 mg/kg every 3 weeks, pembrolizumab 10 mg/kg every 2 weeks, or four cycles of ipilimumab 3 mg/kg every 3 weeks.

The coprimary end points were progression-free survival and overall survival; secondary end points were overall response rate, duration of response, and safety, with an exploratory analysis for health-related quality of life.

At week 12 and every 6 weeks thereafter per RECIST 1.1, tumor response was assessed with an independent central blinded radiographic review and investigator-assessed immune-related response criteria.