Pfizer and Astellas' prostate cancer drug for previously treated patients approved by FDA

21-Nov-2023 - Last updated on 21-Nov-2023 at 11:37 GMT

Astellas Pharma Inc. and Pfizer Inc. today announced that the companies received approval from the US Food and Drug Administration (FDA) for a supplemental New Drug Application for small-molecule drug Xtandi (enzalutamide).

This was following FDA expedited development and review programs (Priority Review designation, Fast Track designation, Real-time Oncology Review), based on results from the phase 3 Embark trial.

With this approval, Xtandi becomes the first and only androgen receptor signaling inhibitor approved by the FDA for the treatment of patients with nonmetastatic castration-sensitive prostate cancer (nmCSPC) with biochemical recurrence at high risk for metastasis (high-risk BCR).

Patients with nmCSPC with high-risk BCR may be treated with Xtandi with or without a gonadotropin-releasing hormone (GnRH) analog therapy.

In their research, the companies found that those men who have undergone definitive prostate cancer treatment, including radical prostatectomy, radiotherapy or both, an estimated 20-40% will experience biochemical recurrence (BCR) within ten years. About nine out of ten men with high-risk BCR will develop metastatic disease and one in three will die as a result of their metastatic prostrate cancer.

Previously treated prostate cancer

“For patients who were previously treated for prostate cancer and had achieved remission, only to later receive the distressing news of disease recurrence with a risk of metastasis, the emotional toll can be profound,” said Courtney Bugler, president, and CEO of ZERO Prostate Cancer.

“This approval of Xtandi is a promising treatment option for the community, offering a ray of hope to patients and their caregivers during these challenging times.”

Neal Shore is chief medical officer of strategic innovation and pharmacy at GenesisCare, USA, and director of the Carolina Research Center and primary investigator for the trial.

He said: “Having had the privilege of taking care of patients with prostate cancer for nearly 40 years, I have been fortunate to have participated in many of the prostate cancer landscape-changing trials; notably, we have not progressed our evidenced-based care for patients with biochemical recurrence (BCR), also known as nmCSPC, until the completion of the Embark trial.

Important advancement

“Previously, treatment options for these BCR patients, especially those who have a high likelihood of developing metastases were limited. The FDA approval of Xtandi for patients with nmCSPC with BCR at high risk of metastasis represents an important advancement whereby an androgen deprivation signaling inhibitor, enzalutamide, has achieved a standard of care discussion for patient-physician decision-making.”

The approval is based on results from the phase 3 Embark trial, which evaluated Xtandi plus leuprolide, placebo plus leuprolide, and Xtandi (single agent) in patients with nonmetastatic hormone- (or castration-) sensitive prostate cancer (nmHSPC or nmCSPC) with high-risk BCR. Detailed results from the trial were presented as a plenary session during the 2023 American Urological Association Annual Meeting and subsequently published in the New England Journal of Medicine.

“Today’s FDA approval is the culmination of over a decade of research and development as we’ve worked to bring Xtandi forward for as many patients with prostate cancer as possible who may benefit,” said Ahsan Arozullah, senior VP and head of oncology development, Astellas.

“With every milestone, our clinical development program has played an instrumental role in changing the course of patients’ lives. We are proud that Xtandi can now be offered to a subset of men with nonmetastatic castration-sensitive prostate cancer with biochemical recurrence and at high risk for metastases.”

Exciting approval

Chris Boshoff, chief oncology research and development officer and executive vice president at Pfizer, observed that more than 300,000 men in the US have been prescribed Xandi. He said the companies were excited to have this approval expanding the indication for the first time into an earlier setting of the disease.

“This milestone is a testament to Xtandi’s legacy and robust clinical profile, with overall survival demonstrated for patients with metastatic castration-resistant prostate cancer, nonmetastatic castration-resistant prostate cancer, and metastatic castration-sensitive prostate cancer.

“With today’s approval, we look forward to bringing this therapy to even more patients who have nonmetastatic castration-sensitive prostate cancer at high risk for their cancer metastasizing.”

Xtandi is currently under review with other regulatory authorities around the world, including the European Medicines Agency, to support an expanded indication in nmHSPC (or nmCSPC) with high-risk BCR based on the results of EMBARK.