Abstract
Background and Aims
Clinical guidance on the use of drugs is mainly supported by data from premarketing trials. However, results from clinical trials are not necessarily translated into real-world outcomes. The main objective of this study is to assess whether the outcomes of patients with type 2 diabetes mellitus treated under real-world conditions with dipeptidyl peptidase-4 (DPP-4) inhibitors reflect the results obtained from clinical trials.
Methods
This protocol conforms to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) 2015 statement. This systematic review will assess the effects of DPP-4 inhibitors in pre-marketing studies (phase III randomized controlled trials [RCTs]) and in post-marketing real-world outcomes studies (phase IV RCTs and observational studies). A literature search will be performed at Medline, Embase, Cochrane Controlled Register of Trials (CENTRAL) and ClinicalTrials.gov. The following outcomes will be considered: i) efficacy endpoints: mean changes from baseline in hemoglobin A1C (HbA1c), fasting plasma glucose, and body weight, and patients achieving HbA1c <7%; ii) effectiveness endpoints: all-cause mortality, cardiovascular-related mortality, acute myocardial infarction, stroke, hospitalizations, emergency department visits, amputations, nephropathy and retinopathy. The risk of bias will be independently assessed according to the checklist proposed by Downs and Black. Data will be analyzed using descriptive statistics and meta-analysis when applicable.
Results
This review is ongoing and will be finished at the end of 2019.
Conclusions
The most relevant contribution of this study is providing evidence on both external validity of the results of clinical trials and on the extent to which diabetic patient benefit from DPP-4 inhibitors in clinical practice.
