Pfizer has received US Food and Drug Administration (FDA) approval to expand the use of Talzenna (talazoparib) in combination with Xtandi (enzalutamide) for men with a specific type of advanced prostate cancer. Announced on October 26, 2026, the approval allows the combination to be used earlier in the disease, offering a new treatment option for patients whose tumors carry mutations in genes involved in DNA repair.
The expanded approval covers men with homologous recombination repair (HRR) gene-mutated metastatic androgen pathway modulation-naïve or -sensitive prostate cancer. This condition is also known as metastatic hormone-sensitive prostate cancer (mHSPC). HRR gene mutations, including changes in BRCA genes, can affect how cancer cells repair damaged DNA.
Talzenna is a PARP inhibitor that blocks a protein involved in DNA repair, while Xtandi works by blocking androgen receptor signaling, which can help prostate cancer cells grow. By combining these two medicines, the treatment aims to slow cancer progression in patients with HRR gene mutations.
The FDA decision was supported by results from the Phase 3 TALAPRO-3 clinical trial, which included 599 patients with HRR gene-mutated metastatic prostate cancer. Participants received either Talzenna plus Xtandi or a placebo plus Xtandi.
Results showed that the combination reduced the risk of cancer progression or death by 52% compared with Xtandi alone. The benefit was observed in patients with both BRCA and non-BRCA HRR gene mutations. Pfizer also reported that an estimated 77% of patients receiving the combination remained free from radiographic disease progression at three years.
The safety findings were consistent with the known profiles of the two medicines, and researchers did not identify any new safety signals. However, anemia was a key side effect. Severe anemia occurred in 51% of patients receiving the combination, compared with 3% in the control group. Some patients required dose changes, supportive care or treatment discontinuation.
The findings were presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting and published in The New England Journal of Medicine.
The combination was first approved in the US in 2023 for men with HRR gene-mutated metastatic castration-resistant prostate cancer, a later stage of the disease. The latest FDA decision expands its use to patients whose cancer remains sensitive to hormone-based treatment, potentially allowing eligible patients to benefit earlier.
The application was reviewed under the FDA’s Priority Review programme. Pfizer said a corresponding application is also under review by the European Medicines Agency, with further regulatory submissions planned or underway in other markets.
The approval strengthens Pfizer’s prostate cancer portfolio and highlights the growing role of biomarker testing in treatment decisions. Identifying HRR gene mutations can help doctors determine which patients may benefit from targeted therapies.