SILVER SPRING, Md., April 28, 2011 /PRNewswire-USNewswire/ —
The U.S. Food and Drug Administration today approved Zytiga
(abiraterone acetate) in combination with prednisone (a steroid) to
treat patients with late-stage (metastatic) castration-resistant
prostate cancer who have received prior docetaxel
In prostate cancer, the male sex hormone testosterone stimulates
prostate tumors to grow. Drugs or surgery are used to reduce
testosterone production or to block testosterone’s effects.
However, sometimes prostate cancer can continue to grow even when
testosterone levels are low. Men with these cancers are said to
have castration-resistant prostate cancer.
Zytiga is a pill that targets a protein called cytochrome P450
17A1 (CYP17A1) which plays an important role in the production of
testosterone. The drug works by decreasing the production of this
hormone that would stimulate cancer cells to continue growing.
The application was reviewed under the FDA’s priority review
program, which provides for an expedited six-month review for drugs
that may offer major advances in treatment, or provide a treatment
when no adequate therapy exists. Zytiga is being approved ahead of
the product’s June 20, 2011 regulatory goal date.
“Zytiga prolonged the lives of men with late-stage prostate
cancer who had received prior treatments and had few available
therapeutic options,” said Richard Pazdur, M.D., director of the
Office of Oncology Drug Products in the FDA’s Center for Drug
Evaluation and Research.
Zytiga’s safety and effectiveness were established in a
clinical study of 1,195 patients with late-stage
castration-resistant prostate cancer who had received prior
treatment with docetaxel chemotherapy. Patients received either
Zytiga once daily in combination with prednisone two times a day