QTc monitoring during a phase I study: experience with SR271425.

Objective: SR271425 is a thioxanthone cytotoxic drug that induces dose-related cardiac electrophysiologic changes in preclinical models. A phase I trial was conducted to determine the maximally tolerated dose and safety profile, notably cardiac events.

Methods: SR271425 was administered weekly as a 2-hour single intravenous infusion with a fixed 30 mg/m2 increment at each dose level (DL).