h8C3

h8C3 is a **humanized monoclonal antibody** that specifically binds to melanin and is being studied as an experimental therapeutic for metastatic melanoma, particularly as a vehicle for targeted radioimmunotherapy (RIT)[3][4][6][7]. The h8C3 antibody is conjugated with radionuclides such as ^213^Bi (bismuth-213, an alpha-emitter), ^177^Lu (lutetium-177, a beta-emitter), or ^225^Ac (actinium-225, an alpha-emitter), allowing targeted cytotoxic radiation delivery to melanoma cells that express or release melanin in the tumor microenvironment[3][4][6][7]. The mechanism involves direct targeting of extracellular melanin, minimizing off-tumor toxicity by sparing naturally pigmented tissues[4]. Preclinical studies show h8C3 RIT can significantly reduce tumor growth in melanoma models without notable hematologic or systemic side effects, and combination with PD-1 immune checkpoint blockade further increases therapeutic efficacy[3][4][7]. h8C3 and related radioconjugates have not reached clinical trial phases as of the current review[6][4][7].

Brand names

h8C3h-8C3h 8C3

Other names

h8C3h-8C3h 8C3