Data on Merck’s MK-3475 from Largest Study to Date of Investigational Anti-PD-1 Antibody in Advanced Melanoma Highlighted at ASCO 2014

Source: Market Watch, June 2014

CHICAGO, Jun 2, 2014 (Canada NewsWire via COMTEX) — MK-3475 as monotherapy shows estimated overall survival rates of 69 percent at one year across 411 advanced melanoma patients with varying stages of disease and prior therapy

Durable responses and consistent tolerability profile observed across doses, including patients with or without prior ipilimumab therapy

Phase 3 trials ongoing or planned across lines of therapy, including adjuvant treatment

CHICAGO, June 2, 2014 /CNW Telbec/ – Merck MRK -0.40% today announced new data from the company’s large ongoing Phase 1b study (KEYNOTE-001) evaluating MK-3475, Merck’s investigational anti-PD-1 antibody, as a single agent (monotherapy) in 411 patients with advanced melanoma. Following treatment with MK-3475, the estimated overall survival (OS) rate at one year was 69 percent across all patients studied, including 74 percent in patients without prior ipilimumab therapy (current standard therapy) and 65 percent in patients who had progressive disease on or following ipilimumab. At 18 months, the estimated OS was 62 percent. The median OS has not been reached, with some patients receiving treatment for more than two years.

These new data will be presented today in an oral session by Dr. Antoni Ribas, professor, Hematology/Oncology and Surgery, and director of the Tumor Immunology Program at the Jonsson Comprehensive Cancer Center, University of California, Los Angeles at the 50(th) Annual Meeting of the American Society of Clinical Oncology (ASCO 2014) in Chicago (Abstract #LBA9000; 3:00 PM CDT; Location – E Arie Crown Theater).

“The data presented today provide further evidence of durable anti-tumor activity stimulated by MK-3475 as a single agent in patients suffering from malignant melanoma," said Dr. Roger M. Perlmutter, president, Merck Research Laboratories. “While we await further confirmation through controlled clinical trials, the survival rates seen with MK-3475 therapy, including in patients with advanced disease who have failed other therapies, support the use of immune manipulation in cancer care."

New Data for MK-3475 in Advanced Melanoma These data from 411 patients with advanced melanoma enrolled in multiple cohorts from KEYNOTE-001, the largest Phase 1b study to date of an anti-PD-1 antibody, will be highlighted as part of the ASCO 2014 Press Program. KEYNOTE-001 involved seven advanced melanoma cohorts including patients with varying stages of disease and prior lines of therapy. At baseline, 56 percent of patients had the most advanced stage of disease (M1c) (n=232) and 77 percent of patients had received at least one prior systemic therapy (n=316). Interim data from a single cohort of 135 patients from KEYNOTE-001 were first presented at ASCO 2013 and published concurrently in the New England Journal of Medicine. More recently, updated findings from this cohort were reported at the 10(th) International Congress of the Society for Melanoma Research (November 2013).

Objective Response Rates (ORR) as Assessed by irRC and RECIST Criteria among 411 Patients with Advanced Melanoma