Phase I and clinical pharmacology trial of crisnatol (BWA770U mesylate) using a monthly single-dose schedule.

Crisnatol is a novel lipophilic arylmethylaminopropanediol with significant antineoplastic activity in a variety of murine and human tumor models which functions as a DNA intercalator. In this Phase I trial, a 6-h infusion of the drug was administered i.v. in 700 to 1500 ml of 5% dextrose in water every 28 days. Eighty-five courses at doses of 7.5 to 516 mg/m2 were administered to 43 patients with refractory solid tumors. Reversible neurological toxicity was dose limiting at 516 mg/m2 and was manifested as somnolence, dizziness, blurred vision, unsteady gait, and alpha-slowing on electroencephalogram at the end of infusion. All neurological signs and symptoms were reversible. No hematological toxicity was observed. Other toxicities included phlebitis, mild to moderate nausea and vomiting, reversible sinus node arrest in one patient, and hypertension. Crisnatol plasma concentrations were determined by high-pressure liquid chromatography. After infusion, plasma concentrations declined biexponentially with a terminal t1/2 of 2.9 h. Using a two-compartment model, the mean apparent volume of distribution at steady state and total-body clearance were 58.8 liters/m2 and 18.3 liters/h/m2, respectively, indicative of extensive tissue distribution and rapid hepatic clearance. Peak plasma levels occurred at the end of infusion and correlated with the onset of neurological toxicity. The recommended Phase II dose for this schedule is 388 mg/m2.

Phase I evaluation of crisnatol (BWA770U mesylate) on a monthly extended infusion schedule.

Crisnatol is an arylmethylaminopropanediol derivative that has shown promise as an antitumor agent in preclinical testing. In a phase I trial using a monthly six-hour infusion schedule the recommended dose for future phase II trials was found to be 388 mg/m2. Neurologic toxicity was dose-limiting in that trial and correlated with the attainment of a threshold plasma concentration of greater than 4.5 micrograms/ml. In this study we treated 15 patients with escalating doses of crisnatol from 450 mg/m2 to 900 mg/m2 administered at a rate of 50 mg/m2/hr over 9, 12, 15, and 18 hours. Toxicity was mild to moderate at all dose levels. However, serious central nervous system effects were noted in one patient at 900 mg/m2 over 18 hours whose plasma level was 6.5 micrograms/ml. This study has demonstrated higher total doses of crisnatol can be given if the drug is administered as a prolonged infusion in an attempt to avoid high plasma levels of the agent.