ABSTRACT
The primary goal of phase I trials involving cytotoxic agents in oncology is to find the “maximum tolerated dose” (MTD). The MTD is defined as the greatest dose that can be administered to patients with an ‘acceptable’ level of toxicity. The amount of toxicity at a given dose levels is considered ‘acceptable’ if the proportion of patients treated at that dose who experience a ‘dose-limiting toxicity’ (DLT) is less than or equal to a target level of toxicity, usually in the range of 20% to 33%. The definition of a DLT is study specific, and depends on the type of agent being studied.
