Does the treatment of type 2 diabetes mellitus with the DPP-4 inhibitor vildagliptin reduce HbA1c to a greater extent in Japanese patients than in Caucasian patients?

• Published in: Vascular health and risk management 2016-01, Vol.12 (Issue 1), p.9-12
• Main Authors: Foley, James E, Bhosekar, Vaishali, Kawamori, Ryuzo
• Format: Article
• Language: English
• Subjects: Adamantane - adverse effects; Adamantane - analogs & derivatives; Adamantane - therapeutic use; Aged; Asian Continental Ancestry Group; Baseline HbA1c; Biomarkers - blood; Blood Glucose - drug effects; Blood Glucose - metabolism; Body mass index; Caucasians; Clinical medicine; Clinical trials; Diabetes; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - diagnosis; Diabetes Mellitus, Type 2 - drug therapy; Diabetes Mellitus, Type 2 - enzymology; Diabetes Mellitus, Type 2 - ethnology; Diabetes therapy; Dipeptidyl Peptidase 4 - metabolism; Dipeptidyl-Peptidase IV Inhibitors - adverse effects; Dipeptidyl-Peptidase IV Inhibitors - therapeutic use; Down-Regulation; Drug therapy; European Continental Ancestry Group; Female; Glucose; Glycated Hemoglobin A - metabolism; Health Status Disparities; Hemoglobin; Homeostasis; Humans; Insulin resistance; Japan - epidemiology; Japanese; Male; Middle Aged; Nitriles - adverse effects; Nitriles - therapeutic use; Population; Pyrrolidines - adverse effects; Pyrrolidines - therapeutic use; Randomized Controlled Trials as Topic; Short Report; Treatment Outcome; Type 2 diabetes; Vildagliptin; White people
• ISSN: 1178-2048; 1176-6344; 1178-2048
• DOI: 10.2147/VHRM.S96971

Previous work suggests that Japanese patients with type 2 diabetes mellitus (T2DM) may respond more favorably to a DPP-4 (dipeptidyl peptidase-4) inhibitor than Caucasians. We aimed to compare the efficacy of the DPP-4 inhibitor vildagliptin (50 mg twice daily [bid]) between Japanese and Caucasian populations. This analysis pooled data from 19 studies of drug-naïve patients with T2DM who were treated for 12 weeks with vildagliptin 50 mg bid as monotherapy. The pool comprised Japanese patients (n=338) who had been treated in Japan and Caucasian patients (n=1,275) who were treated elsewhere. Change from baseline (Δ) in glycated hemoglobin (HbA1c) at 12 weeks (in millimoles per mole) versus baseline HbA1c (both in percentage National Glycohemoglobin Standardization Program units [NGSP%] and millimoles per mole) for each population was reported. Universal HbA1c in millimoles per mole was calculated from either the Japanese Diabetes Society or the NGSP% HbA1c standards. At baseline, mean values for Japanese and Caucasian patients, respectively, were as follows: age, 59 years and 56 years; % male, 69% and 57%. The average HbA1c was reduced from 7.90% to 6.96% (Japanese Diabetes Society) and from 8.57% to 7.50% (United States National Glycohemoglobin Standardization Program), while HbA1c was reduced from 63 mmol/mol to 53 mmol/mol and from 70 mmol/mol to 58 mmol/mol in Japanese and Caucasians, respectively. ΔHbA1c increased with increasing baseline in both populations. The slopes were the same (0.41, r (2)=0.36; and 0.41, r (2)=0.15), and the intercepts were 15.4 mmol/mol and 17.2 mmol/mol, respectively. In Japanese patients, mean ΔHbA1c was greater by 1.7 mmol/mol (0.2% NGSP HbA1c) at any given baseline HbA1c than in Caucasians (P=0.01). The present pooled analysis suggests that Japanese patients respond better to vildagliptin treatment compared with Caucasians. However, when glycemic control was corrected by using the same glycemic standard, the difference in HbA1c reduction between these populations was not clinically meaningful.