The results from the Alpharadin (radium-223 chloride) trial #msg-63944830 show that a bone targeted therapy (not an “anti-cancer” drug) can improve OS in CRPC patients with bone metastases. I'd say Alpharadin is an anti-cancer drug. Alpharadin, a radiopharmaceutical whose active ingredient is based on radium-223. This drug product is deposited into areas of new bone formation where it releases alpha radiation, thereby attacking the bone metastases. Xgreva is different.