Labcorp Launches FDA-Approved Companion Diagnostic to Identify Patients with Ovarian Cancer Eligible for KEYTRUDA®

BURLINGTON, N.C., April 22, 2026 /PRNewswire/ -- Labcorp (NYSE: LH), a global leader of innovative and comprehensive laboratory services, today announced the nationwide availability of Agilent Technologies' PD-L1 IHC 22C3 pharmDx, the only companion diagnostic approved by the U.S. Food and Drug Administration (FDA) to identify patients with platinum-resistant ovarian cancer who may be eligible for Merck's KEYTRUDA®.i KEYTRUDA (pembrolizumab) and KEYTRUDA QLEX™ (pembrolizumab and berahyaluronidase alfa-pmph) are the first FDA-approved PD-1 inhibitors available as part of a complete treatment regimen for eligible patients with platinum-resistant ovarian cancer.ii Helping Patients Access Critical New Treatment Options Approximately 80% of individuals with ovarian cancer experience recurrence after initial therapy, and many develop resistance to platinum-based chemotherapy, leading to limited treatment options and poor survival outcomes.