In order to evaluate the efficacy of drug therapy for obesity, it is necessary to establish criteria for a favorable treatment outcome. In clinical practice we can measure the success of treatment in each case, using such indicators as the number of lost pounds, the successful prevention of recurrent weight gain, slowing the rate of weight gain in the future, improved by the presence of complications of obesity and improve the quality of life and functional performance. A reasonable and clinically significant outcome of treatment for most patients - a weight loss of 10% in the first 6 months of treatment.
Criteria for the use of new drugs to treat obesity drugs to treat obesity, the last credible clinical trials (randomized, double-blind controlled study for 1 year) must meet the following requirements: 1) weight reduction should be 5% higher (statistically significant difference) than with placebo; 2) compared with placebo, drug therapy should lead to weight loss of more than 5% for larger (statistically significant) number of patients. In addition, we recommend studies for 2-year treatment of patients, to determine the efficacy of the conservation of body weight at an optimal level. However, assessment of drug efficacy through randomized controlled clinical trials may be complicated by the use of other drugs as a subsidiary, which is reflected as part of the study protocol. The level of weight loss in patients taking a placebo (dummy), varies widely. It depends on the type of diet, exercise, behavior therapy program that is used in the research process.