In vitro cytotoxicity and selectivity of cAC10-vcMMAE. CD30⁺ Karpas 299 cells were plated at 5000 cells/well and were exposed to a graded titration of cAC10, cAC10-vcMMAE, or an isotype-matched irrelevant control immunoglobulin or its conjugate with vcMMAE. Cells were assessed for cytotoxicity by Alamar Blue assay after 96 hours of continuous exposure, as described in “Materials and methods.” The percentage viability, relative to untreated control wells, was plotted versus ADC concentration. Results for each study are the average of quadruplicate determinations. Error bars indicate ± SD.