FDA approves label update for Zytiga

FDA has approved label update for abiraterone acetate (Zytiga, Janssen) in chemotherapy-naïve men with metastatic castration-resistant prostate cancer.

Zytiga is an antiandrogen which acts by inhibiting CYP17, an enzyme found in testicular, adrenal and prostatic tumor tissue that is required for androgen biosynthesis. Research has shown that prostate cancer tumor cells develop adaptive mechanisms including the ability to produce androgen, which helps to fuel their survival, suggesting that reducing androgen production is key to helping men with metastatic castration-resistant prostate cancer (mCRPC) manage their illness.

Related:Pharmacologic treatment of prostate cancer

FDA has now approved a label update for Zytiga to include statistically significant overall survival results in chemotherapy-naïve men with mCRPC. The new approval is based on the final analysis of the phase 3 COU-AA-302 study, which showed that Zytiga plus prednisone demonstrated a median overall survival (OS) of 34.7 months compared to 30.3 months in participants treated with placebo plus prednisone.

"Since its launch in 2011, ZYTIGA has helped change the treatment paradigm for metastatic castration-resistant prostate cancer, treating more than 150,000 men worldwide," said Cynthia Guzzo, MD, vice president, medical affairs, Janssen Scientific Affairs, LLC. 

Related: Read more FDA drug approvals

Since its first US approval in 2011, more than 60,000 men have been prescribed Zytiga for the treatment of prostate cancer. The most common adverse events associated with the use of Zytiga include fatigue, joint swelling or discomfort, edema, hot flush, diarrhea, vomiting, and cough. 

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