Actinium Ac 225 AKY-1189

**Semantic type:** Pharmacologic Substance

**Definition:** A radioconjugate composed of AKY-1189, a miniprotein binder targeting the cell surface adhesion molecule and tumor-associated antigen (TAA) nectin-4 (PVRL4), labeled with the alpha-emitting radioisotope actinium Ac 225, with potential antineoplastic activity. Upon administration of actinium Ac 225 AKY-1189, AKY-1189 targets and binds to nectin-4 expressed on tumor cells. Upon binding, the radioisotope moiety delivers a cytotoxic dose of alpha radiation to nectin-4-expressing tumor cells. Nectin-4, a TAA belonging to the nectin family, is overexpressed in a variety of cancers, but has a restricted distribution in normal tissue.

**Synonyms:** - Actinium Ac 225 Labeled-AKY-1189 - Actinium Ac 225-AKY-1189 - [225Ac]-AKY-1189