Correlation between C_max and AUC of loncastuximab tesirine–conjugated antibody during cycle 1 and baseline peripheral CD19⁺ B cells. (A) C_max. (B) AUC. Linear regression models were used with natural log of baseline peripheral CD19⁺ B-cell values as the independent variable and natural log of C_max or AUC as the dependent variable. Zero baseline CD19⁺ cells was set to 0.1 cells per μL and LN(0.1) = −2.30. The estimated slope (standard error) was −0.0617 (0.0239; 95% CI, −0.109 to −0.0143) for C_max and −0.232 (0.0370; 95% CI, −0.305 to −0.158) for AUC.