Pfizer Inc. has announced that the US Food and Drug Administration (FDA) has accepted for Priority Review its supplemental New Drug Application (sNDA) for Talzenna (talazoparib) in combination with Xtandi (enzalutamide) for the treatment of men with homologous recombination repair (HRR) gene-altered metastatic Castration-Sensitive Prostate Cancer (mCSPC), also known as metastatic Hormone-Sensitive Prostate Cancer (mHSPC). The FDA has assigned a Prescription Drug User Fee Act (PDUFA) action date in the last quarter of 2026.

If approved, the expanded indication would allow the Talzenna-Xtandi combination to be used at an earlier stage of metastatic prostate cancer. The therapy is currently approved in the US for patients with HRR gene-mutated mCRPC.

The regulatory submission is supported by findings from the Phase 3 TALAPRO-3 clinical trial, which demonstrated that Talzenna plus Xtandi reduced the risk of radiographic disease progression or death by 52 percent compared with placebo plus Xtandi. The study also reported consistent clinical benefit across patients with both BRCA and non-BRCA HRR gene alterations, while maintaining a safety profile consistent with the known characteristics of each therapy and identifying no new safety concerns.

Commenting on the development, Jeff Legos, Chief Oncology Officer at Pfizer, said that treating patients during the hormone-sensitive stage provides an important opportunity to delay disease progression. He added that, if approved, the combination could offer patients with HRR-driven metastatic prostate cancer a new treatment option while highlighting the growing importance of biomarker testing to guide treatment decisions earlier in the disease course.

The TALAPRO-3 results were presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting and simultaneously published in The New England Journal of Medicine. The study enrolled 599 patients across North America, Europe, South America and the Asia-Pacific region, evaluating Talzenna in combination with Xtandi against placebo plus Xtandi in patients with HRR gene-altered mCSPC.

In parallel with the US review, the indication expansion is also under evaluation by the European Medicines Agency (EMA). Talzenna plus Xtandi is currently approved for the treatment of HRR gene-mutated mCRPC in more than 60 countries, with approved indications varying by market.

Talzenna is an oral PARP inhibitor designed to interfere with DNA damage repair mechanisms in cancer cells, while Xtandi is an androgen receptor pathway inhibitor widely used in the treatment of advanced prostate cancer. Together, the combination represents a precision medicine approach aimed at improving outcomes for patients with genetically defined forms of metastatic prostate cancer.