Comparative Effectiveness of Glimepiride versus Linagliptin as add-on to Metformin in Type-2-Diabetes Mellitus

Abstract

Background: In addition to lifestyle modifications, metformin is the recommended first-line pharmacotherapy for patients with type 2 diabetes mellitus (T2DM). The use of glimepiride or linagliptin as add-on to metformin (GM or LM) has been noticed on prescriptions in major pharmacies in Nigeria.
 Aims: The aim of this study was to compare the efficacy of glimepiride or linagliptin as add-on to metformin in T2DM.
 Methods: A preliminary case-crossover randomized experimental/observational study comprising 30 participants (i.e., 15 for each of the combination therapies) was designed and designated GM and LM groups, respectively. Baseline physiological and health-indicators of the participants were primarily observed followed by a practical/analytical drug efficacy measurement of postprandial blood glucose (PPBG) levels at 1, 2, 4, and 6 h once weekly for 2 weeks and thereafter crossover to the other regimen for another two weeks’ assessment.
 Results: Baseline results were consistent across subgroup analyses in both treatment types. The statistical analysis demonstrated that LM achieved significant PPBG lowering potential compared to baseline blood glucose status (p<0.05). There was no significant difference in the observed physiological and biochemical indicators of organ system function for both treatments during the study. Treatment with LM was associated with reduced post-meal blood glucose compared with GM (p<0.05). Postprandial blood glucose change over measurement points were higher with LM (p<0.05).
 Conclusion: Blood glucose control was better achieved with LM compared to GM. Propensity to hypoglycemia was higher with LM. More studies involving larger patient population in several centres are required to validate the outcome of these findings.
 Keywords: Glimepiride, Linagliptin, Metformin, Fasting Blood Glucose, Postprandial blood glucose, Type 2 Diabetes Mellitus