Belantamab mafodotin is a first-in-class antibody-drug conjugate (ADC) approved for the treatment of relapsed or refractory multiple myeloma (RRMM). It consists of a humanized, afucosylated anti-BCMA (B-cell maturation antigen) monoclonal antibody conjugated to the potent microtubule-disrupting agent monomethyl auristatin F (MMAF) via a non-cleavable linker. The ADC binds to BCMA on myeloma cells, is internalized, and releases its payload, leading to targeted apoptosis. It was granted accelerated approval by the U.S. FDA and conditional approval by the EMA based on impressive single-agent response rates. However, it carries a notable ocular toxicity risk (keratopathy), requiring strict monitoring. Following confirmatory Phase III trial results that did not meet the prespecified criteria for superiority over standard care, its U.S. approval was withdrawn (though it remains available in other regions under specific conditions).