Serial Assessment of High-Sensitivity Cardiac Troponin and the Effect of Dapagliflozin in Patients With Heart Failure With Reduced Ejection Fraction: An Analysis of the DAPA-HF Trial.

BACKGROUND: Circulating high-sensitivity cardiac troponin T (hsTnT) predominantly reflects myocardial injury, and higher levels are associated with a higher risk of worsening heart failure and death in patients with heart failure with reduced ejection fraction. Less is known about the prognostic significance of changes in hsTnT over time, the effects of dapagliflozin on clinical outcomes in relation to baseline hsTnT levels, and the effect of dapagliflozin on hsTnT levels. METHODS: DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) was a randomized, double-blind, placebo-controlled trial of dapagliflozin (10 mg daily) in patients with New York Heart Association class II to IV symptoms and left ventricular ejection fraction ≤40% (median follow-up, 18.2 months). hsTnT (Roche Diagnostics) was measured at baseline in 3112 patients and at 1 year in 2506 patients. The primary end point was adjudicated worsening heart failure or cardiovascular death. Clinical end points were analyzed according to baseline hsTnT and change in hsTnT from baseline to 1 year. Comparative treatment effects on clinical end points with dapagliflozin versus placebo were assessed by baseline hsTnT. The effect of dapagliflozin on hsTnT was explored. RESULTS: Median baseline hsTnT concentration was 20.0 (25th-75th percentile, 13.7-30.2) ng/L. Over 1 year, 67.9% of patients had a ≥10% relative increase or decrease in hsTnT concentrations, and 43.5% had a ≥20% relative change. A stepwise gradient of higher risk for the primary end point was observed across increasing quartiles of baseline hsTnT concentration (adjusted hazard ratio Q4 versus Q1, 3.44 [95% CI, 2.46-4.82]). Relative and absolute increases in hsTnT over 1 year were associated with higher subsequent risk of the primary end point. The relative reduction in the primary end point with dapagliflozin was consistent across quartiles of baseline hsTnT (P-interaction=0.55), but patients in the top quartile tended to have the greatest absolute risk reduction (absolute risk difference, 7.5% [95% CI, 1.0%-14.0%]). Dapagliflozin tended to attenuate the increase in hsTnT over time compared with placebo (relative least squares mean reduction, -3% [-6% to 0%]; P=0.076). CONCLUSIONS: Higher baseline hsTnT and greater increase in hsTnT over 1 year are associated with worse clinical outcomes. Dapagliflozin consistently reduced the risk of the primary end point, irrespective of baseline hsTnT levels. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03036124.

Assessment of Saxagliptin Efficacy: Meta-Analysis of 14 Phase 2 and 3 Clinical Trials.

INTRODUCTION: This meta-analysis of data from 14 phase 2 and 3, double-blind, randomized, controlled 12- and 24-week studies (N = 4632) summarizes saxagliptin efficacy in patients with type 2 diabetes (T2D) across treatment regimens. METHODS: Patients received saxagliptin 5 mg/d or control as either monotherapy (n = 1196 vs placebo), add-on therapy (n = 2139 vs placebo and n = 514 vs uptitrated sulfonylurea), or initial combination therapy (n = 619 vs control monotherapy). Patients with renal impairment received saxagliptin 2.5 mg/d or placebo (n = 164). RESULTS: Mean baseline glycated hemoglobin (A1C) ranged from 8.07% to 9.43% for the saxagliptin and control groups across treatment regimens. A1C reduction from baseline was greater with saxagliptin versus control for all studies combined (mean treatment difference [95% CI]: -0.55% [-0.63%, -0.47%]) and when used as monotherapy (-0.52% [-0.63, -0.40%]), add-on (-0.55% [-0.69%, -0.40%] vs placebo; -0.72% [-0.88%, -0.56%] vs uptitrated sulfonylurea), initial combination therapy (-0.54% [-0.73%, -0.35%] vs control monotherapy), and in patients with renal impairment (-0.42% [-0.75%, -0.09%]). Similar reductions in A1C versus control were noted for patients <65 years (-0.55% [-0.67%, -0.43%]) and ≥65 years (-0.54% [-0.69%, -0.38%]) and for men (-0.54% [-0.69%, -0.40%]) and women (-0.55% [-0.64%, -0.47%]) across treatment regimens. More patients achieved A1C <7% (39% vs 23%) and A1C ≤6.5% (24% vs 14%) with saxagliptin than with placebo or active-control treatment. Saxagliptin versus control was associated with a reduction in glucagon area under the curve (AUC) from baseline and increases in insulin AUC, C-peptide AUC, and the homeostasis model assessment of ß-cell function. CONCLUSION: Results of this meta-analysis demonstrate the consistency of saxagliptin efficacy in different subgroups of patients with T2D across treatment regimens. FUNDING: AstraZeneca.