We are in the fortunate position because the treatment of men with metastatic castration-resistant prostate cancer (mCRPC) continues to evolve as new agents with the ability to extend survival gain FDA approval. The most recently FDA approved treatment, the alpha emitting radiopharmaceutical radium-223 (Xofigo) was approved for men with bone metastatic prostate cancer.
Most other of the newly approved treatments was designed with the initial intention of providing an increase in overall survival (OS), but Xofigo is different. Like the other already approved radio emitting agents Strontium and Samarium which are beta-emitting agents Xofigo was initially explored solely as a palliative treatment option. However, the investigation quickly changed once it was discovered in very early trials that Xofigo, not like the other agents, also improved survival in addition to providing palliative benefit.
Besides a survival advantage, Xofigo also provides a great measure of superiority over the beta-emitting agents (which irradiate a large area including bone marrow) because as a alpha-emitting agent it only irradiates a very localized area. Since the vast majority of prostate cancer bone metastasis are in the bone and not in the marrow, Xofigo is very affective in treating these mets while not damaging the bone marrow, a significant advantage over the beta emitting treatments.
Xofigo is a game changer with a huge potential for a major role in our treatment protocol.
Joel T. Nowak, M.A., M.S.W.