Effectiveness in clinical practice versus efficacy of dipeptidyl peptidase-4 inhibitors in clinical trials for type 2 diabetes: protocol for systematic review

INTRODUCTION: Data supporting the use of oral antidiabetic drugs mainly rely on data from premarketing clinical trials. Real-world data studies are crucial to evaluate effectiveness of drugs. The aim of this systematic review is to compare the results obtained for efficacy and effectiveness endpoints on clinical trials and those obtained from routine clinical practice of dipeptidyl peptidase-4 inhibitors. METHODS AND ANALYSIS: This systematic review will include randomised controlled trials and observational studies evaluating the efficacy and effectiveness of dipeptidyl peptidase-4 inhibitors, respectively. A literature search will be performed at Medline, Embase, Cochrane Controlled Register of Trials and ClinicalTrials.gov. Search terms comprised the drug name (including the pharmacotherapeutic class and the international non-proprietary name). Data on haemoglobin A1C, blood glucose and body weight will be retrieved. The risk of bias will be independently assessed according to the checklist proposed by Downs and Black. Data will be analysed using descriptive statistics and meta-analysis when applicable. ETHICS AND DISSEMINATION: Ethical approval is not required as no primary data are collected. This systematic review will be disseminated through a peer-reviewed publication and at conference meetings.