Figure 2.

Pharmacokinetic studies evaluating ADC concentrations using radiolabeled ADCs. Clearance of M9346A–sulfo-SPDB–[3H]DM4 (A) and J2898A–SMCC–[3H]DM1 (B) conjugates from plasma of CD-1 mice. All agents were injected iv as a single 10 mg/kg dose. Concentrations of total ADC were measured by counting the radioactivity in plasma arising from the tritium label on the maytansinoid. These findings suggest that maytansinoid conjugates, regardless of linker type, with drug–antibody ratios (DAR) ranging from 2 to 6, have a better therapeutic index than conjugates with very higher DAR (>9). Reproduced and altered with permission from Sun et al. Bioconjug. Chem. 2017, 28, 1371–1381 [52].