Radium Ra 224-labeled Calcium Carbonate Microparticles

**Semantic type:** Pharmacologic Substance

**Definition:** A radiopharmaceutical composed of biodegradable calcium carbonate microspheres labeled with the alpha-emitting radioisotope radium Ra 224, with antineoplastic activity. Upon intraperitoneal (IP) administration of the radium Ra 224-labeled calcium carbonate microparticles, Ra 224 kills tumor cells through local emission of high energy alpha particles, causing DNA double-strand breaks. The short range effects of alpha emission allows for localized DNA damage with limited toxicity to nearby healthy tissue.

**Synonyms:** - 224Ra-labeled Calcium Carbonate Micro-particles - Alpha-emitting 224Ra Calcium Carbonate Microspheres - Ra-224 Alpha-emitting Calcium Carbonate Microparticles - Radspherin