Merck Keytruda in triple-negative breast cancer (TNBC) study misses its pre-specified primary endpoint of superioroverall survival (OS) compared to chemotherapy

KENILWORTH, N.J.–(BUSINESS WIRE)–Merck (NYSE: MRK), known as MSD outside the United States and Canada,
today announced that the Phase 3 KEYNOTE-119 trial evaluating KEYTRUDA,
Merck’s anti-PD-1 therapy, as monotherapy for the second- or third-line
treatment of patients with metastatic triple-negative breast cancer
(TNBC) did not meet its pre-specified primary endpoint of superior
overall survival (OS) compared to chemotherapy (capecitabine, eribulin,
gemcitabine or vinorelbine). Other endpoints were not formally tested
per the study protocol because the primary endpoint of OS was not met.
The safety profile of KEYTRUDA in this trial was consistent with that
observed in previously reported studies involving patients treated with
KEYTRUDA monotherapy; no new safety concerns were identified. Results
will be presented at an upcoming medical meeting.

“Metastatic triple-negative breast cancer is an aggressive and
challenging disease to treat, especially after progression on initial
standard-of-care treatment,” said Dr. Roy Baynes, senior vice president
and head of global clinical development, chief medical officer, Merck
Research Laboratories. “While we are disappointed by the outcome of this
monotherapy trial, we are continuing to study KEYTRUDA in earlier stages
of the disease and in combination with chemotherapy to address the unmet
medical need of patients with triple negative breast cancer. We are
grateful to the patients and investigators for their participation in
this important study.”

The KEYTRUDA breast cancer clinical development program encompasses
several internal and external collaborative studies, including three
ongoing registration-enabling studies in TNBC.