Phase I

Phase I of clinical trials or “dose finding trials” are the first step after gaining permission to test the drug in humans after undergoing discovery and preclinical trials.

The primary focus of a Phase I trial is the safety. These trials study the distribution, metabolism, excretion, and toxicity of the drug. It is also the time of dose escalation and determining the most frequent and serious adverse events.

The secondary focus is finding preliminary evidence of the activity of the drug.

Phase I trials are conducted on a small number of volunteers, usually less than 50. Most of these volunteers are healthy individuals.

Source: Ursino, M., Zohar, S., Lentz, F., Alberti, C., Friede, T., Stallard, N., & Comets, E. (2017). Dose-finding methods for Phase I clinical trials using pharmacokinetics in small populations. Biometrical journal. Biometrische Zeitschrift, 59(4), 804–825.