Dapagliflozin in Patients with Heart Failure and Reduced Ejection Fraction (DAPA-HF)

Authors, Journal, Affiliations, Type, DOI

• Authors: John J.V. McMurray, Scott D. Solomon, Silvio E. Inzucchi, Lars Køber, Mikhail N. Kosiborod, Felipe A. Martinez, Piotr Ponikowski, Marc S. Sabatine, and the DAPA-HF Trial Committees and Investigators
• Journal: New England Journal of Medicine
• Affiliations: BHF Cardiovascular Research Centre, University of Glasgow; Brigham and Women's Hospital/Harvard Medical School; Yale University School of Medicine; Rigshospitalet Copenhagen; and 410 centres in 20 countries
• Type: Phase 3 randomised, double-blind, placebo-controlled trial
• DOI: https://doi.org/10.1056/NEJMoa1911303
• Funding: AstraZeneca

Overview

DAPA-HF randomised 4,744 patients with HFrEF (LVEF ≤40%, NYHA II–IV) to dapagliflozin 10 mg OD or placebo on top of optimised background therapy including ARNi/ACEi/ARB, beta-blocker, and MRA. Over a median of 18.2 months, dapagliflozin reduced the primary composite of worsening HF or CV death (HR 0.74; 95% CI 0.65–0.85; P<0.001; NNT=21). All-cause mortality was also significantly reduced (HR 0.83; P=0.017). Critically, 55% of participants had no type 2 diabetes, establishing that SGLT2 inhibition benefits HFrEF through glucose-independent mechanisms. DAPA-HF is the landmark trial that elevated SGLT2i to the fourth pillar of HFrEF GDMT (Class I / COR 1A in ESC 2021 and AHA 2022).

Keywords

Heart failure with reduced ejection fraction; SGLT2 inhibitor; dapagliflozin; cardiovascular death; worsening heart failure; diabetes-independent benefit; KCCQ; renal protection; NYHA functional class

Key Takeaways

Trial Design

• Phase 3 RCT; n=4,744; 410 centres; 20 countries; enrolment February 2017 – August 2018; median follow-up 18.2 months
• Inclusion: Age ≥18, LVEF ≤40%, NYHA II–IV, NT-proBNP ≥600 pg/mL (≥400 if prior HF hospitalisation within 12 months; ≥900 if AF/AFL on baseline ECG)
• Background therapy required: ACEi, ARB, or sacubitril-valsartan + beta-blocker; MRA encouraged; devices (ICD, CRT) per guideline
• Exclusion: eGFR <30 mL/min/1.73 m², systolic BP <95 mmHg, type 1 diabetes, prior SGLT2i intolerance
• Randomisation stratified by T2DM status (42% established T2DM + 3% newly diagnosed; 55% no T2DM)

Primary Outcome

• Composite worsening HF (hospitalisation or urgent visit requiring IV therapy) or CV death:
  • Dapagliflozin: 386/2,373 (16.3%) vs placebo: 502/2,371 (21.2%)
  • HR 0.74 (95% CI 0.65–0.85; P<0.001); NNT=21 (95% CI 15–38)

Secondary Outcomes

• First worsening HF event: HR 0.70 (95% CI 0.59–0.83) — HF hospitalisations dapagliflozin 9.7% vs placebo 13.4%
• CV death: HR 0.82 (95% CI 0.69–0.98) — 9.6% vs 11.5%
• All-cause death: HR 0.83 (95% CI 0.71–0.97) — 11.6% vs 13.9%
• Total hospitalisations for HF + CV deaths (recurrent events): Rate ratio 0.75 (95% CI 0.65–0.88; P<0.001) — 567 vs 742 total events
• KCCQ total symptom score at 8 months: More patients with ≥5-point improvement (58.3% vs 50.9%; OR 1.15; P<0.001); fewer with significant deterioration (25.3% vs 32.9%; OR 0.84; P<0.001)
• Prespecified renal composite (≥50% eGFR decline / ESRD / renal death): No significant difference between groups

Diabetes-Independent Benefit

• Benefit of dapagliflozin was statistically identical in patients with T2DM and without T2DM (subgroup interaction non-significant)
• First large trial to demonstrate cardiovascular benefit of an SGLT2i in non-diabetic HF patients, establishing glucose-independent mechanisms as primary mediators

Subgroup Analyses

• Treatment benefit generally consistent across 14 prespecified subgroups including LVEF subgroups (≤25%, 26–32%, 33–40%), eGFR, NT-proBNP, aetiology (ischaemic ~50%), sex, age, race, and NYHA class
• Possible attenuation in NYHA III/IV vs II — the only subgroup with suggested heterogeneity; however, other severe-disease markers (worse LVEF, worse renal function, high NT-proBNP) did not show attenuation, making this finding uncertain
• Sacubitril-valsartan subgroup (post hoc): HR 0.75 (95% CI 0.50–1.13) vs HR 0.74 (0.65–0.86) in those not on ARNi — consistent benefit; low ARNi use at baseline (~10%) limits precision

Safety

• Serious volume depletion: 1.2% vs 1.7% (P=0.23) — no difference
• Serious renal adverse events: 1.6% vs 2.7% (P=0.009) — significantly lower with dapagliflozin
• Major hypoglycaemia: rare; confined to patients with T2DM
• Diabetic ketoacidosis: rare; confined to patients with T2DM
• Fournier's gangrene: not observed
• Treatment discontinuation for AE: <5% in either group

Limitations of the Document

• Low baseline sacubitril-valsartan use (~10%) — enrolled before ARNi was widely standard; incremental benefit of SGLT2i on top of modern full quadruple GDMT cannot be directly extracted from DAPA-HF
• Less than 5% of participants were Black; relatively few very elderly patients with multiple comorbidities — limits generalisability to these populations
• Median follow-up 18.2 months (range 0–27.8) — longer-term outcomes not available from this trial
• Open questions remain about optimal combination sequencing of all four GDMT pillars and titration timelines
• The renal composite endpoint was not powered to demonstrate a difference, and the protective trend (serious renal AEs 1.6% vs 2.7%) likely reflects a real effect but is not a formal RCT conclusion on renal hard outcomes from this trial

Key Concepts Mentioned

• concepts/Diuretic-Resistance — dapagliflozin acts via proximal tubular SGLT2 (~5% of proximal Na⁺ reabsorption), distinct from acetazolamide's NHE3 blockade (~60%); mild diuretic/natriuretic effect in HFrEF did not cause volume depletion in background loop diuretic users

Key Entities Mentioned

• entities/HFrEF — primary disease context; DAPA-HF established SGLT2i as fourth-pillar Class I GDMT
• entities/Heart-Failure — broader syndrome context; SGLT2i benefit applies across aetiology

Wiki Pages Updated

• wiki/sources/dapagliflozin-hfref-nejm-2019.md — created (this file)
• wiki/entities/HFrEF.md — DAPA-HF trial section added; source_count updated; contradiction added
• wiki/entities/Heart-Failure.md — direct DAPA-HF citation added to HFrEF SGLT2i bullet
• wiki/sourceindex.md — new entry added
• wiki/wikiindex.md — HFrEF entry updated
• log.md — entry appended