Efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin in black/African American patients with type 2 diabetes: Pooled analysis from eight Phase III trials

Background. The prevalence of type 2 diabetes in black/African Americans from North and South America is high; yet data evaluating antidiabetic agents in this population is scarce. To address this gap, we pooled data from the clinical development program for linagliptin. Methods. A retrospective pooled analysis of eight completed randomized, placebo-controlled Phase III trials of linagliptin identified 336 patients with type 2 diabetes who self-identified their ethnicity as black or African American. Participants received linagliptin (n = 173, 5 mg/day) or placebo (n = 163) as monotherapy, or as add-on to other antidiabetic agents, including insulin. The primary end point was the change in glycated hemoglobin (HbA1c) from baseline to week 18 or 24. Results. The placebo-adjusted mean change (95% confidence interval [CI]) in HbA1c from baseline was –0.69% (–0.92 to –0.46; p < 0.0001) at week 18 (eight trials), and –0.64% (–0.90 to –0.39; p < 0.0001) at week 24 (six trials). The placebo-adjusted mean change (95% CI) in fasting plasma glucose from baseline was −11.7 mg/dL (−23.1 to –0.3; p = 0.0446) at week 18 and –14.7 mg/dL (–25.7 to –3.8; p = 0.0087) at week 24. Incidence of investigator-defined hypoglycemia was similar between the two groups (linagliptin, 12.1%; placebo, 11.7%). Overall, the safety profile of linagliptin in this patient group was comparable to that of placebo, with comparable incidence of adverse events; linagliptin was weight-neutral in this patient population. Conclusion. Linagliptin provided clinically significant improvements in glycemic control without increased risk of hypoglycemia and without weight gain, representing a useful type 2 diabetes therapy option for the black/African American population.