Phase I and pharmacologic study of 9-aminocamptothecin colloidal dispersion formulation given as a 24-hour continuous infusion weekly times four every 5 weeks.

Abstract

PURPOSE: 9-Aminocamptothecin (9-AC) is a water-insoluble camptothecin (CMP) derivative that inhibits normal topoisomerase I function. Schedule dependency was noted, with the greatest activity seen in the setting of greater than 24 hours exposure to lactone (L) concentrations > or = 10 nmol/L. In this phase I study, 9-AC was given by a continuous intravenous infusion over 24 hours once weekly times four every 5 weeks. PATIENTS AND METHODS: Twenty patients, of whom 16 had fluorouracil-refractory colorectal cancer (CRC), entered the study. Dose levels were 0.7 mg/m2 (n = 4), 1.4 mg/m2 (n = 3), 1.9 mg/m2 (n = 6), and 1.65 mg/m2 (n = 7). Detailed pharmacokinetic (PK) measurements of 9-AC L and ca..