If the results are promising, the drug is tested in people. There are different kinds of clinical trials. They are not all the same. Do not assume that every study has extremely high risks and questionable benefits. Some studies are risky while others involve very little risk .
Clinical trials occur in phases, building on information learned in an earlier study.
In this phase, a study medication is given to a small group of people for the first time, to learn whether or not it is safe. After a drug is approved, trials may study different formulations of the drug, different age groups, populations and medication interactions. The informed consent is a written document that informs potential study participants of all details of the study medications and the study plan. Researchers are required by law to give potential study participants all the facts known about a study and study drug before the individual agrees to participate. This information must be explained so that it is understood by the participant.