Targeted use of Alpha Particles: Current Status in Cancer Therapeutics

Purpose of review: To summarize the current role of alpha particles in cancer treatment including both clinical and pre-clinical data.Recent findings: Though discovered more than hundred years ago, no targeted alpha emitters have yet to be approved as a systemic approach to cancer therapy.Until recently, most approaches to target alpha particle emitters utilized conjugation with antibodies through chelators.Limited clinical data are available using this approach; most alpha emitters have been studied in pre-clinical models though 213 bismuth has been studied in leukemic patients.The novel alpha emitter 223 radium has been studied more extensively than other agents in this class and a recent large randomized phase III trial data with 223 radium demonstrates overall survival benefit in castrate resistant prostate cancer patients with skeletal metastasis. Summary:The alpha emitter 223 radium is expected to play a significant future role in therapy for bone-metastatic disease and a variety of novel alpha emitters offer the potential for targeted therapy via conjugation with specific antibodies or targeted nanoparticles.