Medicines for Obesity: Appraisal of Clinical Studies with Grading of Recommendations, Assessment, Development, and Evaluation Tool

Abstract

We evaluated the quality of evidence from phase III/IV clinical trials of drugs against obesity using the principles of Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool. Our systematic review evaluates the quality of clinical evidence from existing clinical trials and not the pharmacological efficacy of anti-obesity therapies. A literature search using select keywords in separate was performed in PubMed and ClinicalTrials.gov databases for phase III/IV clinical trials during the last ten years. Our findings indicate that the quality of existing clinical evidence from anti-obesity trials generally ranges from low to moderate. Most trials suffered from publication bias. Less frequently, trials suffered from the risk of bias mainly due to lack of blindness in the treatment. Our work indicates that additional higher-quality clinical trials are needed to gain more confidence in the estimate of the effect of currently used anti-obesity medicines, to allow more informed clinical decisions, thus reducing the risk of implementing potentially ineffective or even harmful therapeutic strategies.

Keywords: GRADE evaluation; clinical evidence; clinical pharmacology; obesity.

Figure 1

Strategy for collecting and evaluating clinical evidence for anti-obesity medicines in the context of this systematic review. PRISMA 2020 flow diagram for new systematic reviews, which included searches of databases and registers only. * GRADE cannot be applied in a single study; thus, in this review, drugs found in only one study were excluded. ** Studies that include clinical trials from 2009 were excluded since our research focuses on the last ten years. *** Studies that include clinical trials evaluated in other included studies. ¥ This study includes two different studies, which we evaluated separately; thus, the number of “Studies included in review” is 24 and not 22 [51].