Efficacy and safety of incretin based therapies: clinical trial data.

OBJECTIVE

Provide a comprehensive overview of efficacy and safety data on incretin-based agents in the treatment of type 2 diabetes.

DATA SOURCES

A PubMed search was conducted for the years 2000-2009, using as keywords the names of glucagon-like peptide-1 (GLP-1) receptor agonists (exenatide and liraglutide) and dipeptidyl peptidase-4 (DPP-4) inhibitors (sitagliptin, alogliptin, and saxagliptin). World Diabetes Congress abstracts from 2008 to 2009 were also searched for clinical studies of these agents.

STUDY SELECTION

The author included randomized controlled trials of incretin therapies that were published in English and enrolled > or =100 participants.

DATA EXTRACTION

Data on the effects of incretins on glycemic control, weight, beta-cell function, blood pressure, lipid levels, safety, and tolerability were extracted and summarized.

DATA SYNTHESIS

A total of 27 randomized controlled studies of incretin therapy were identified and included in the review. GLP-1 receptor agonists and DPP-4 inhibitors were evaluated at different points in the diabetes treatment spectrum, i.e., added to diet and exercise alone (monotherapy) or added to oral antihyperglycemic regimens (combination therapy).

CONCLUSION

In addition to decreasing glycemia in type 2 diabetes, incretin therapies may improve other important parameters, including beta-cell function, blood pressure, and lipid levels, with a low risk for hypoglycemia. A comparison of the study data differentiates the clinical profiles of the GLP-1 receptor agonists, which are associated with weight loss, and DPP-4 inhibitors, which are weight neutral, as well as the individual agents within each class.