Pfizer Inc. (NYSE: PFE) today announced that the U.S. Food and Drug Administration (FDA) accepted for Priority Review a supplemental New Drug Application (sNDA) for TALZENNA® (talazoparib), an oral poly ADP-ribose polymerase (PARP) inhibitor, in combination with XTANDI® (enzalutamide), an androgen receptor pathway inhibitor (ARPI), in 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 set a Prescription Drug User Fee Act (PDUFA) action date in the last quarter of 2026.
TALZENNA plus XTANDI is currently indicated in the U.S. 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.
"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 reinforce 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 (NCT04821622extlink label) 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, and a safety profile consistent with the known profiles of each agent and no new safety signals. These results were presented at the 2026 American Society of Clinical Oncology Annual Meeting and simultaneously published in TheNew England Journal of Medicineextlink label.
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.
About mCSPC
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.1,2 Approximately 5-10% of newly diagnosed cases are mCSPC,3,4 and up to 30% of these patients harbor HRR gene alterations.5
About TALAPRO-3
The Phase 3 TALAPRO-3 trial is a multicenter, randomized, double-blind, placebo-controlled study that enrolled 599 patients with mCSPC (with ≤3 months of ADT [chemical or surgical] with or without an approved ARPI in the mCSPC setting) at sites in the U.S., Canada, Europe, South America, and the Asia-Pacific region. Patients with histologically/cytologically confirmed adenocarcinoma of the prostate without neuroendocrine differentiation, small cell, or signet cell features and with alterations in one or more HRR genes (as per HRR12 gene panel) in the trial were randomized to receive TALZENNA 0.5 mg/day plus XTANDI 160mg/day, or placebo plus XTANDI 160mg/day.
The primary endpoint of the trial is investigator-assessed rPFS, defined as the time from the date of randomization to radiographic progression in soft tissue per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), or in bone per Prostate Cancer Working Group 3 (PCWG3) criteria by investigator assessment, or death, whichever occurs first. Secondary endpoints include OS, objective response rate, duration of response, and patient-reported outcomes.
