Efficacy and Safety of Linagliptin in Black/African American Patients with Type 2 Diabetes: A 6-month, Randomized, Double-blind, Placebo-controlled Study.

Objective: Although black/African American individuals are disproportionately affected by type 2 diabetes, there is scant clinical trial information available on antidiabetes therapies in this group. We compared linagliptin with placebo in black/African American adults who were treatment-naïve or receiving one oral antidiabetes drug.

Methods: Of 226 patients randomized to 24 weeks' linagliptin 5 mg/day or placebo, 208 had baseline and at least one on-treatment glycated hemoglobin (HbA1c) measurement. Mean baseline HbA1c was 8.6% in the linagliptin group (n = 98) and 8.68% in the placebo group (n = 110). The primary outcome was change in HbA1c from baseline to week 24.

Results: By week 24, mean HbA1c changes were -0.84% with linagliptin and -0.25% with placebo (treatment difference, -0.58%; P<.001), and more patients in the linagliptin group achieved HbA1c <7.0% (26.8% vs. 8.3%; P = .001) or an HbA1c reduction ≥0.5% (54.1% vs. 30.0%; P<.001). Mean weight loss was -1.1 kg in both groups. During the treatment period, 8 of 98 linagliptin-group patients and 17 of 110 placebo-group patients required rescue therapy (odds ratio, 0.5; P = .14). For postprandial glucose, values were available for few patients (11 placebo, 10 linagliptin), and thus the between-group difference was associated with wide confidence intervals (CIs) (difference, -1.97 mg/dL; 95% CI, -53.80 to 49.86; P = .94). In the overall study population, a similar proportion of patients in both groups had adverse events (58.5% vs. 61.7%); most events were mild or moderate and considered unrelated to study drug. Investigator-defined hypoglycemia was rare (3 linagliptin-group patients and 1 placebo-group patient), with no severe events (requiring external assistance).

Conclusion: This study confirms that linagliptin is efficacious and well tolerated in black/African American patients with type 2 diabetes.