Cyclosam
Samarium Sm 153-DOTMP is a radioconjugate composed of the phosphonic acid chelator DOTMP (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylenephosphonic acid) conjugated to the beta- and gamma-emitting radioisotope samarium Sm 153, with potential antineoplastic activity. Upon administration of samarium Sm 153-DOTMP, the DOTMP moiety targets and binds to growing bone, thereby selectively delivering samarium Sm 153-mediated cytotoxic radiation to bone tumor and metastases, which may help destroy bone metastases and mitigate pain from bone metastases.