A newly approved diagnostic test is now available nationwide, helping to identify patients with a difficult-to-treat form of ovarian cancer who may be eligible for the first FDA-approved immunotherapies for their condition. The move aims to quickly connect eligible patients with the new drugs, KEYTRUDA and KEYTRUDA QLEX, which have been shown to improve survival.
For patients with platinum-resistant ovarian cancer, where the disease returns and stops responding to standard chemotherapy, treatment options have been severely limited. Approximately 80% of ovarian cancer patients experience recurrence, and platinum resistance leads to poor outcomes. The U.S. Food and Drug Administration approved the two pembrolizumab-based treatments in February for patients whose tumors express a specific biomarker, PD-L1. A companion diagnostic test, the PD-L1 IHC 22C3 pharmDx, is required to identify these eligible individuals.
Labcorp has now launched this test nationwide, enabling hospitals and clinics across the country to determine a patient's eligibility. "Platinum-resistant ovarian cancer is incurable, and current treatment options offer limited and short-lived benefits for patients," said Dr. Marcia Eisenberg, chief scientific officer at Labcorp. "By making this companion diagnostic available nationwide, Labcorp is helping clinicians rapidly identify eligible patients and connecting them with a therapy that offers new hope." The company prepared for the launch through an early validation program to ensure rapid availability following the drug approvals.
The approval of the drugs was based on the Phase 3 KEYNOTE-B96 trial. The study found that KEYTRUDA plus chemotherapy, with or without bevacizumab, demonstrated a statistically significant improvement in both progression-free survival and overall survival for eligible patients compared to chemotherapy alone. This represents a meaningful advance for a patient population with high unmet need.
With the diagnostic test now widely accessible, oncologists can systematically screen patients for PD-L1 expression. The broader hope is that this streamlined pathway from testing to targeted treatment will become a standard part of care, offering a renewed sense of possibility for women facing this challenging diagnosis. The integration of a precise diagnostic with a new, effective therapy marks a significant step toward more personalized and hopeful treatment for advanced ovarian cancer.