Radium-223 chloride shows efficacy against castration-resistant prostate cancer

Bayer HealthCare Pharmaceuticals’ investigational radium-223 chloride has met the primary and secondary endpoints of a Phase III prostate cancer trial.

The randomised double-blind and placebo-controlled trial showed that radium-223 chloride improved overall survival in 44% of patients with castration-resistant prostate cancer and symptomatic bone metastases.

Radium-223 chloride demonstrated median overall survival of 14 months, compared to 11.2 months for the placebo group, a 49% improvement in time to prostate-specific antigen progression, and 33% of patients showed total alkaline phosphatise normalisation compared to 1% for placebo group.

The primary endpoint of the study was overall survival, while secondary endpoints included time to occurrence of SREs, changes and time to progression in prostate-specific antigen and alkaline phosphatise, safety and impact on quality of life measures.

Trial investigator Oliver Sartor said radium-223 chloride is the first bone-targeted, alpha-emitting radiopharmaceutical to demonstrate a survival benefit in men with castration-resistant prostate cancer and symptomatic bone metastases.

The company plans to file a new drug application with the US Food and Drug Administration in mid-2012.