Traditionally, the criteria of treatment efficacy in clinical studies are physical findings and laboratory values. However, our opinion is that it is also important to evaluate quality of life of healthy volunteers who can also be participants of specific clinical trials such as bioequivalence studies and Phase I studies. In order to reinforce the introduction of humanistic element into the process of clinical trial we have developed a specialized quality-of-life questionnaire for healthy volunteers who take part in bioequivalence studies of drugs. Several questions in questionnaire were connected with physical condition and emotional problems that may be experienced by the volunteers during the participation in the bioequivalence study and in what way it could affect the normal social life of respondents. The survey of 58 volunteers, taking part in the bioequivalence study, has showed that 43.10 % of them evaluate their health status as “excellent” and 44.83 % as “very good”. At the same time, 79.31 % of the respondents answered that their health condition is almost the same as at the beginning of the trial. The survey has demonstrated the positive changes of volunteers’ quality of life during the study. The obtained results proved the beneficial tendency in volunteers’ well-being and the level of social satisfaction before and after their participation in the study on bioequivalence.