The FDA ( Food and Drug Administration ) has approved Xofigo ( Radium Ra 223 dichloride ) to treat men with symptomatic late-stage castration-resistant prostate cancer that has spread to bones but not to other organs. It is intended for men whose cancer has spread after receiving medical or surgical therapy to lower testosterone.
The FDA reviewed Xofigo under the agencys priority review program, which provides for an expedited review of drugs that appear to provide safe and effective therapy when no satisfactory alternative therapy exists, or offer significant improvement compared to marketed products.
Xofigo binds with minerals in the bone to deliver radiation directly to bone tumors, limiting the damage to the surrounding normal tissues.
Xofigo is the second prostate cancer drug approved by the FDA in the past year. In August 2012, the FDA approved Xtandi ( Enzalutamide ) to treat men with metastatic castration-resistant prostate cancer that has spread or recurred, even with medical or surgical therapy to minimize testosterone. Xtandi is approved for patients who have previously been treated the chemotherapy drug Docetaxel.
Xofigos safety and effectiveness were evaluated in a single clinical trial of 809 men with symptomatic castration-resistant prostate cancer that spread to bones but not to other organs. Patients were randomly assigned to receive Xofigo or a placebo plus best standard of care.
The study was designed to measure overall survival. Results from a pre-planned interim analysis showed men receiving Xofigo lived a median of 14 months compared to a median of 11.2 months for men receiving placebo. An exploratory updated analysis conducted later in the trial confirmed Xofigos ability to extend overall survival.
The most common side effects reported during clinical trials in men receiving Xofigo were nausea, diarrhea, vomiting and swelling of the leg, ankle or foot. The most common abnormalities detected during blood testing included anemia, lymphocytopenia, leukopenia, thrombocytopenia and neutropenia.
According to the National Cancer Institute ( NCI ), an estimated 238,590 men will be diagnosed with prostate cancer and 29,720 will die from the disease in 2013 in the United States.
Source: FDA, 2013