A drug to treat prostate cancer has been approved by the US Food and Drug Administration. The drug, Xtandi ® (enzalutamide), had previously been approved for castration-resistant prostate cancer (CRPC) but has now had its indication broadened to also include patients with non-metastatic CRPC. The original source article can be found here, at Business Wire.
About Prostate Cancer
Prostate cancer occurs in the prostate, which only people born as male have, and is located underneath the bladder and around the urethra. It is about the size of a walnut. It is the most common form of cancer in males in the UK, with approximately one out of eight men developing it.
Prostate cancer tends to be slow growing, so may go unnoticed for years. Many people won’t experience any symptoms of the disease at all. However, others might develop urination issues if the cancer grows large enough to affect the urethra. Since symptoms may not develop, it’s important for people to learn about their risk of developing this type of cancer.
Castration-resistant prostate cancer (CRPC), the form that Xtandi had previously been approved as a treatment for, is a certain subset of prostate cancer. In CRPC the disease progresses even after the body’s level of testosterone is reduced to be very low using hormone therapy.
According to the original article, non-metastatic CRPC, the subset of prostate cancer that Xtandi has just received approval to treat, is the term used when doctors don’t think that the cancer has spread to other areas of the body, and the level of prostate-specific antigen is rising. This state often leads to the development of metastatic CRPC.
About the New Indication for Xtandi ® (Enzalutamide)
The FDA first approved Xtandi to treat CRPC in 2012. Now, the FDA has approved a supplemental New Drug Application for Xtandi for the treatment of certain patients with non-metastatic CRPC. Xtandi should always be prescribed under the guidance of a doctor, and more detailed information about the drug and its uses can be found here.
The recent approval came following the FDA’s Priority Review (a faster process than normal). This makes Xtandi, according to the original article, the first and only oral treatment approved by the FDA for both CRPC and non-metastatic CRPC. The FDA’s decision was based on a recent Phase 3 clinical trial called Prosper.
The Phase 3 Prosper Trial
This trial gave patients with non-metastatic CRPC Xtandi along with androgen deprivation therapy (ADT), and this treatment combination was found to significantly decrease mortality and risk of metastasis (cancer spreading to new areas).
On average (median), patients taking the combination of Xtandi and ADT achieved metastasis-free survival for 36.6 months, compared to 14.7 months for those only taking ADT.