(ChemotherapyAdvisor) – The novel alpha-pharmaceutical radium-223 chloride may provide a new standard of care for the treatment of patients with castration-resistant prostate cancer (CRPC) with bone metastases, a study presented during the 2012 Genitourinary Cancers Symposium has concluded.
ALSYMPCA, a phase III, double-blind, randomized, multinational study, randomized 615 patients to receive radium-223 injections 50 kBq/kg IV every 4 weeks and 307 patients to placebo; both groups also received best standard of care, according to A. Oliver Sartor, MD, of the Tulane Cancer Center, New Orleans, LA, and colleagues. Primary end point was overall survival (OS); secondary end points included skeletal-related events (SREs).
Following a planned interim analysis (n=809), the study was unblinded June 2011. These data showed radium-223 significantly improved OS: median OS was 14 months vs. 11.2 months for placebo. Radium-223 significantly delayed time to first SRE, including spinal cord compression, pathological bone fracture, and external beam radiotherapy. Median time to SREs was 13.6 months for the radium-223 arm vs. 8.4 months for placebo. Time to surgical intervention was comparable between the two arms.
The effectiveness of combining radium-223 with other drugs is being explored, and radium-223 is currently being tested in patients with breast cancer who have bone metastases.
The 2012 Genitourinary Cancers Symposium is sponsored by the American Society of Clinical Oncology, American Society for Radiation Oncology, and the Society of Urologic Oncology.