FDA Grants Priority Review for XTANDI® in Non-Metastatic Castration-Sensitive Prostate Cancer with High-Risk Biochemical Recurrence

If approved, XTANDI would become the first and only novel hormone therapy approved in this earlier type of prostate cancer

Reno, Nevada (UroToday.com) --Pfizer Inc. (NYSE: PFE) and Astellas Pharma Inc. (TSE: 4503, President and CEO: Naoki Okamura, "Astellas") announced that the U.S. Food and Drug Administration (FDA) has accepted and granted Priority Review for the companies' supplemental New Drug Application (sNDA) for XTANDI® (enzalutamide) for the treatment of patients with non-metastatic castration-sensitive prostate cancer (nmCSPC; also known as non-metastatic hormone-sensitive prostate cancer or nmHSPC) with high-risk biochemical recurrence (BCR). The FDA grants Priority Review to medicines that may offer significant advances in treatment or may provide a treatment where no adequate therapy exists. The Prescription Drug User Fee Act (PDUFA) date for an anticipated FDA decision is in Q4 2023.

"The FDA's granting of a Priority Review designation reinforces the need to bring new treatment options for patients with high-risk biochemical recurrent nmCSPC," said Chris Boshoff, M.D., Ph.D., Chief Oncology Research and Development Officer, Executive Vice President, Pfizer. "We believe the EMBARK data demonstrate the potential of XTANDI, if approved, to help patients earlier in the course of their disease, building on XTANDI's foundation as an existing standard of care in prostate cancer."
"Biochemical recurrence can be one of the first indicators that prostate cancer is returning or will spread, particularly among those patients that experience rapid PSA doubling times," said Ahsan Arozullah, M.D., MPH, Senior Vice President and Head of Oncology Development, Astellas. "The goal of treatment in this setting is to delay the spread of the cancer cells to other parts of the body. The addition of XTANDI to leuprolide has shown greater clinical benefit compared to placebo plus leuprolide, and we look forward to working with the FDA and other global regulatory authorities to bring XTANDI to these patients."

The sNDA is based on results from the Phase 3 EMBARK trial, which evaluated patients with nmCSPC with high-risk BCR across three study arms: XTANDI plus leuprolide (n=355), placebo plus leuprolide (n=358), or XTANDI monotherapy (n=355). The study met its primary endpoint of metastasis-free survival (MFS) for the XTANDI plus leuprolide arm, demonstrating a statistically significant 58% reduction in the risk of metastasis or death over placebo plus leuprolide (Hazard Ratio [HR]: 0.42; 95% Confidence Interval [CI], 0.30–0.61; p<0.0001). The overall safety profile was consistent with the known safety profile of each of the medicines. The most common adverse events in those treated with XTANDI plus leuprolide were fatigue, hot flush, and arthralgia and in those treated with XTANDI monotherapy were fatigue, gynecomastia, and arthralgia. Detailed results from the trial were presented as a plenary session during the 2023 American Urological Association Annual Meeting on April 29.

The sNDA for XTANDI in nmCSPC with high-risk BCR is being reviewed under the Real-Time Oncology Review (RTOR) program and Project Orbis, two initiatives of the FDA designed to bring safe and effective cancer treatments to patients as early as possible. RTOR allows the FDA to review components of an application before submission of the complete application. Project Orbis provides a framework for concurrent submission and review of oncology medicines by participating international partners.

The EMBARK data are being discussed with other regulatory authorities around the world to support potential additional license applications for XTANDI in this indication in 2023 and beyond.

Source: Astellas Pharma Inc. (2023). FDA Grants Priority Review for XTANDI® in Non-Metastatic Castration-Sensitive Prostate Cancer with High-Risk Biochemical Recurrence [Press release]. https://newsroom.astellas.us/2023-08-23-FDA-Grants-Priority-Review-for-XTANDI-R-in-Non-Metastatic-Castration-Sensitive-Prostate-Cancer-with-High-Risk-Biochemical-Recurrence.