Answer:
The term "pilot" is very relevant to the plane take off, and in clinical research it means trying a medication on a small group of patients who are severely ill and has no other treatment alternative. The purpose is to make a last try to treat such patients, and if the trial medication works, the researchers start to find out how to expand the use of medication. Anyhow, in all clinical researches, and as a fixed rule, any research can not be conducted without the agreement of the health authorities (FDA, EEC..etc), and with the adherence and application of the international guidelines (ICH GCP, DoH..etc)