Castration-Sensitive Prostate Cancer Drug Gets FDA Greenlight

FDA expands the indication of abiraterone acetate (Zytiga) to include more patients with prostate cancer.

The FDA today approved abiraterone acetate (Zytiga) tablets in combination with prednisone for the treatment of metastatic high-risk castration-sensitive prostate cancer (CSPC), according to a press release.

Abiraterone acetate previously gained FDA approval in 2011 for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC) who had previously received chemotherapy. Additionally, the drug is indicated to treat patients with CRPC.

The new approval in CSPC was granted based on positive findings from the LATITUTDE clinical trial, which included 1199 patients with CSPC. Patients were randomized to receive abiraterone acetate 1000-mg plus prednisone 5-mg once daily or placebo. The FDA noted that patients in both cohorts were treated with gonadotropin-releasing hormone therapy or had a bilateral orchiectomy, according to the release.

“LATITUDE was a large global trial which produced impressive and clinically significant results in overall survival,” principal investigator Karim Fizazi, MD, PhD, head of the Medical Oncology Department at Institute Gustave Roussy, Villejuif, France, said in a press release. “With today’s approval, abiraterone acetate plus prednisone could become a standard of care for patients with metastatic high-risk castration-sensitive prostate cancer.”

The primary efficacy endpoint of the trial was overall survival (OS); however, median OS was not estimable in the abiraterone acetate cohort and 34.7 months in the placebo cohort, according to the FDA.

Additionally, the median time-to-initiation of chemotherapy was not achieved in patients treated with abiraterone acetate plus prednisone and nearly 40 months for placebo patients.

Common adverse events include hypertension, hot flush, hypokalemia, increased alanine aminotransferase or aspartate aminotransferase, headache, urinary tract infection, upper respiratory tract infection, and cough.

The FDA said that the recommended dose of patients with metastatic CSPC is abiraterone acetate 1000-mg plus prednisone 5-mg orally once per day. Patients should also receive a gonadotropin-releasing hormone analog or have a bilateral orchiectomy, according to the release.

The FDA previously granted priority review to this designation and approval was granted more than 1 month early, according to the release.

“Today’s approval marks an important step in addressing the unmet needs of patients with metastatic high-risk castration-sensitive prostate cancer by providing an option that has demonstrated improvement in overall survival,” Andree Amelsberg, MD, vice president of Oncology Medical Affairs at Janssen Biotech, Inc, said in a press release. “This milestone is an exciting turning point for researchers and clinicians, and most importantly, for patients suffering from this disease and their families who now have an important additional therapeutic option.”