OREANDA-NEWS. June 02, 2015. TESARO, Inc. (NASDAQ: TSRO), an oncology-focused biopharmaceutical company, and Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced a collaboration  to evaluate the combination of TESARO’s niraparib plus Merck’s anti-PD1 therapy, KEYTRUDA® (pembrolizumab), in a Phase 1/2 clinical trial.

This trial is planned to evaluate the preliminary safety and efficacy of niraparib plus KEYTRUDA in patients with triple negative breast cancer or ovarian cancer. This trial will be conducted by TESARO and Merck, through a subsidiary, and is expected to begin by the end of 2015.

“The combination of a PARP inhibitor and anti-PD-1 antibody in this study has the potential to build upon the responses already observed with each of these compounds as monotherapies,” said Mary Lynne Hedley, Ph.D., president and chief operating officer of TESARO. “Treatment options for patients with triple negative breast cancer are extremely limited, and we look forward to assessing this exciting new approach.”

“We continue to expand the clinical development program for KEYTRUDA across a range of cancers, both as monotherapy and in combination, and are delighted to add this new study to the more than 40 combination studies that are underway or planned with KEYTRUDA,” said Dr. Eric Rubin, vice president and therapeutic area head, oncology early stage development, Merck Research Laboratories. “The combination of these two mechanisms has the potential to provide a new approach to help women with triple negative breast cancer and ovarian cancer.”