Re-adjudication of the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS) with study-level meta-analysis of hospitalization for heart failure from cardiovascular outcomes trials with dipeptidyl peptidase-4 (DPP-4) inhibitors

Background: Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS) assessed the cardiovascular (CV) safety of sitagliptin versus placebo on CV outcomes in patients with type 2 diabetes and CV disease and found sitagliptin noninferior to placebo. Subsequently, based on feedback from FDA, the Sponsor of the trial, Merck & Co., Inc., engaged a separate academic research organization, the TIMI Study Group, to re-adjudicate a prespecified set of originally adjudicated events. Methods: TIMI adjudicated in a blinded fashion all potential hospitalization for heart failure (HHF) events, all potential MACE+ events previously adjudicated as not an endpoint event, and a random subset (similar to 10%) of MACE+ events previously adjudicated as an endpoint event. An updated study-level meta-analysis of four randomized, placebo-controlled, CV outcomes trials with dipeptidyl peptidase 4 (DPP-4) inhibitors was then performed. Results: After re-adjudication of potential HHF events in the intent-to-treat population, there were 224 patients with a confirmed event in the sitagliptin arm (1.05/100 person-years) and 239 patients in the placebo arm (1.13/100 person-years), corresponding to a hazard ratio (HR) of 0.94 (95% confidence interval [95% CI]: 0.78-1.13, p = .49). Concordance between the outcome of the original adjudication and the re-adjudication for HHF events was 82.7%. The meta-analysis of CV outcomes trials with DPP-4 inhibitors with placebo and involving 43 522 patients yielded an HR of 1.07 (95% CI: 0.83-1.39), with moderate heterogeneity (p = .45, I-2 = 62.07%). Conclusion: The results of this independent re-adjudication process and analyses of CV outcomes from TECOS were consistent with the original adjudication results and overall study findings. An updated study-level meta-analysis showed no overall significant risk for HHF with DPP-4 inhibitors, but with statistical heterogeneity.

Automated summary

This study re-adjudicated the cardiovascular safety of Sitagliptin and performed a meta-analysis of related trials. The results showed similar incidence of heart failure between Sitagliptin and placebo, and overall no significant risk for heart failure with DPP-4 inhibitors.