Abstract 4531: Effects of drug load on therapeutic index for antibody-maytansinoid conjugates

Antibody-drug conjugates (ADCs) are being actively pursued as a new modality to treat cancer following the regulatory approval of Adcetris@ and Kadcyla@. ADCs consist of a cytotoxic agent, or drug, conjugated to a targeting antibody (Ab) through a linker. The two approved ADCs (and most ADCs now in the clinic) are heterogeneous conjugates with an average molar drug to Ab ratio (DAR) of 3-4 (potentially ranging from 0-8 for individual molecules)....