In phase 1 clinical trials, the experimental medicine is administered for the first time in humans to assess its safety, tolerability, and pharmacokinetics. During this stage, low doses of that medicine are administered to a small number of participants, under the constant observation and monitoring of the assigned medical and nursing teams.
The trial details vary according to each protocol and depend on the drug characteristics. The number of volunteers needed also varies with the protocol and its objectives.
When the center is selected for a trial, this trial is presented to potential participants. Those who accept to participate will undergo several clinical evaluations to make sure that they meet all the necessary criteria to be included in the study.
Usually, the phase 1 clinical trials require hospitalization (one or several days, according to the protocol) to standardize all the trial conditions (meals, sample collection, and exercise, among others) and ensure the safety of the participant.