A supplemental New Drug Application (sNDA) for Pfizer’s Talzenna (talazoparib) in combination with Xtandi (enzalutamide) has been accepted for Priority Review by the US FDA. The application is to treat men with homologous recombination repair (HRR) gene-altered metastatic castration-sensitive prostate cancer (mCSPC), also known as metastatic hormone-sensitive prostate cancer (mHSPC).
Talzenna (talazoparib) is an oral poly ADP-ribose polymerase (PARP) inhibitor and Xtandi (enzalutamide) is an androgen receptor pathway inhibitor (ARPI). The combination is currently indicated in the US for men with HRR gene-mutated metastatic castration-resistant prostate cancer (mCRPC). If approved, the sNDA would expand the combination’s use to mCSPC, an earlier stage of disease.
Metastatic castration-sensitive prostate cancer (mCSPC) is a form of advanced prostate cancer – the second most common cancer in men worldwide – that has spread beyond the prostate but is still sensitive to androgen deprivation therapy. Approximately 5-10% of newly diagnosed cases are mCSPC, and up to 30% of these patients harbour HRR gene alterations.
“For men living with metastatic prostate cancer, intervening during the hormone-sensitive stage represents an important opportunity to delay progression before the disease becomes more difficult to manage,” said Jeff Legos, Chief Oncology Officer, Pfizer. “If approved, Talzenna plus Xtandi would offer patients with HRR-driven disease a new treatment option that could help them live longer without their cancer progressing. The data supporting this application also reinforces the importance of biomarker testing to inform treatment decisions as early as possible.”
The application is supported by data from the phase 3 TALAPRO-3 trial (NCT04821622) which showed Talzenna plus Xtandi reduced the risk of radiographic progression or death by 52% versus placebo plus Xtandi, with consistent benefit across patients with BRCA and non-BRCA HRR gene alterations. The safety profile was consistent with the known profiles of each agent and there were no new safety signals.
The results were presented at the 2026 American Society of Clinical Oncology Annual Meeting and simultaneously published in The New England Journal of Medicine.
The use of Talzenna plus Xtandi in HRR gene-mutated mCSPC is also under review by the European Medicines Agency. Talzenna plus Xtandi is currently approved for mCRPC in more than 60 countries, with specific indications varying by country.
The FDA has set a Prescription Drug User Fee Act (PDUFA) action date in the last quarter of 2026.