Radium RA 223 dichloride has been approved by the FDA for the treatment of symptomatic metastatic castration-resistant prostate cancer (mCRPC) that has spread to the bones but not to any other organs.
Radium RA 223 dichloride (Xofigo) has been approved by the FDA for the treatment of symptomatic metastatic castration-resistant prostate cancer (mCRPC) that has spread to the bones but not to any other organs.
The alpha radiation-emitting drug, known as radium-223 and formerly known as Alpharadin, was granted priority review in February. The FDA approved the drug three months ahead of schedule through its expedited priority review program. Radium-223 is an injectable therapeutic alpha particle-emitting drug designed to have an antitumor effect on bone metastases in patients with mCRPC.
The approval was based on results from the phase III, double-blind, randomized, multinational ALSYMPCA trial. The trial was designed to compare radium-223 with a placebo and best standard care in patients with CRPC and at least two bone metastases.
“Xofigo binds with minerals in the bone to deliver radiation directly to bone tumors, limiting the damage to the surrounding normal tissues,” Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, said in a statement.
According to updated results presented at the 2012 American Society of Clinical Oncology (ASCO) Annual Meeting, radium-223 significantly improved overall survival (OS), with patients in the radium-223 arm of the study experiencing a median OS of 14.9 months compared with 11.3 months in the placebo arm (hazard ratio [HR] = 0.695; 95% CI, 0.581-0.832; P = .00007). The time to the first skeletal-related event was a median of 15.6 months in the radium-223 arm of the study, a significant prolongation over the 9.8 months in the placebo arm (HR = 0.658; 95% CI, 0.522-0.830; P = .00037).
The most common side effects reported during clinical trials were nausea, diarrhea, vomiting and swelling of the leg, ankle, or foot, according to the FDA. The most common abnormalities detected in blood tests included anemia, lymphocytopenia, leukopenia, thrombocytopenia, and neutropenia.
The drug is marketed by Bayer Pharmaceuticals.
Parker C, Nilsson S, Heinrich D, et al. Updated analysis of the phase III, double-blind, randomized, multinational study of radium-223 chloride in castration-resistant prostate cancer with bone metastases (ALSYMPCA).J Clin Oncol