The pharmacokinetics of a murine monoclonal antibody vinca conjugate (KS1/4‐DAVLB) was investigated in 13 patients with adenocarcinomas who received single intravenous doses ranging from 40 to 250 mg/m2and in three patients who were administered 1.5 mg/kg every 48 to 72 hours for up to 15 doses. Five patients in the single‐dose study also received 100 μCi of [3H]‐KS1/4‐DAVLB. Overall mean values for the pharmacokinetic variables were as follows: elimination half‐life, 31.5 hours; distribution volume, 4.43 L; and clearance, 0.09 L/hr. KS1/4‐DAVLB demonstrated linear elimination kinetics in both the single‐ and multiple‐dose studies. Significant concentrations of KS1/4‐DAVLB were noted in a pleural effusion. Ten percent of the radioactive dose was recovered in the urine and 20% in the feces over a 5‐day period. Small molecular weight vinca species were detected in the feces but not in the serum.Clinical Pharmacology and Therapeutics(1990)47,36–41;