Prostate Cancer Treatment Xofigo Offers Hope Dr. Stephen Lemon talks about the cancer drug Xofigo ( radium-223 dichloride ) for the treatment of patients with late stage prostate cancer that has spread to the bones but not to other organs, such as the lung, liver or brain, and where patients have already received treatment to lower testosterone. As testosterone may cause prostate cancer to grow, the goal of some surgery and drug treatments is to lower the level of this male hormone in the body. When the cancer spreads or comes back after such treatment, it is sometimes referred to as castration resistant. Xofigo is being studied for the treatment of bone metastasis in other cancers as well. Xofigo is marketed by Bayer Pharmaceuticals.