DAPA-HF & DEFINE-HF: Dapagliflozin in heart failure with reduced ejection fraction
Bottom line:
- Among patients with symptomatic heart failure with reduced ejection fraction (HFrEF), the SGTL2 inhibitor dapagliflozin reduced the risk of a composite of CV death, HF hospitalization or urgent visit for HF requiring IV diuretics vs placebo (NNT 21), death (NNT 44) & HF hospitalizations (NNT 28) at 1.5 years in patients with OR WITHOUT diabetes.
- Dapagliflozin also improves quality of life beyond the clinically important difference as early as 12 weeks (NNT 10-14), without any differences in adverse effects (e.g. hypovolemia, kidney injury, severe hypoglycemia).
Patients (n=4744)
- From Feb 2017-Aug 2018, 8134 screened -> 4744 randomized 
- Included - HF with ejection fraction of 40% or less (HF with reduced ejection fraction [HFrEF]) 
- NYHA functional class 2-4 
- NT-proBNP - >900 pg/mL if AF/atrial flutter 
- >400 pg/mL if HF hospitalization within 1 year 
- >600 pg/mL if neither of the above 
 
- +/- type 2 diabetes 
- Stable doses (at least 4 weeks) of standard HF medications (ACEI/ARB/ARNI + beta-blocker as tolerated, + MRA) 
 
- Key exclusion criteria: Type 1 diabetes, symptomatic hypotension or SBP <95, eGFR <30 
- Baseline (average/proportions) - 66 y/o 
- Female 23% 
- White 70%, Asian 24%, Black 5% 
- North America 14% 
- HF characteristics - Etiology: Ischemic (56%), non-ischemic (36%), unknown (8%) 
- Prior HF hospitalization 47% 
- NYHA 2 (68%), 3 (32%), 4 (<1%) 
- LVEF 31% 
- NT-proBNP ~1400 
 
- PMHx: Diabetes 42%, AF 38% 
- Clinical variables: SBP 122, eGFR 66 
- Therapies - Diuretic 93%, digitalis 19% 
- ACEI 56%, ARB 27%, ARNI 11% 
- Beta-blocker 96% 
- MRA 71% 
- ICD 26%, CRT 7% 
- Antihyperglycemics (% of those with T2DM): Metformin (51%), sulfonylurea (22%), DPP4i (16%), GLP1RA (1%), insulin (27%) 
 
 
Intervention & Control
- Intervention: Dapagliflozin 10 mg daily - Dose reduced to 5 mg/d or temporary discontinuation if acute, unexpected decline in eGFR, volume depletion, or hypotension (or to avoid these) 
 
- Control: Matching placebo 
- Standardized monitoring: Follow-up at 14 days & 60 days (focus on HF/volume assessment, adverse events, & evaluation of renal function & potassium), then q4 months 
Outcomes
CV outcomes @ median 18 months
- Primary outcome (CV death, HF hospitalization, or urgent visit for HF resulting in IV therapy): Dapagliflozin 16.3% vs placebo 21.2% - Hazard ratio (HR) 0.74 (95% confidence interval 0.65-0.85); Absolute difference 4.9%, NNT 21 
- CV death: 9.6% vs 11.5%; HR 0.82 (0.69-0.98) 
- HF hospitalization: 9.7% vs 13.4%; HR 0.70 (0.59-0.83) 
- Consistent across subgroups (HR 0.75 for type 2 diabetes, HR 0.73 for those without diabetes) 
 
- All-cause mortality: Dapagliflozin 11.6% vs placebo 13.9%; HR 0.83 (0.71-0.97) 
Quality of life (QoL) @ month 8
- Measured using Kansas City Cardiomyopathy Questionnaire [KCCQ] total symptom score, range from 0 [worst] to 100 [best], Minimal clinically-important difference is a 5-point improvement/worsening) 
- Mean change: +6.1 vs +3.3 (/100); “win ratio” 1.18 (1.11-1.26) 
- Improvement 5+ points: Dapagliflozin 58.3% vs placebo 50.9%, odds ratio (OR) 1.15 (1.08-1.23) 
- Deterioration 5+ points: Dapagliflozin 25.3% vs placebo 32.9%, OR 0.84 (0.78-0.90) 
Safety @ median 18 months (none statistically significant vs placebo)
- Discontinuation due to adverse events: 4.7% vs 4.9% 
- Volume depletion: 7.5% vs 6.8% (p=0.4); serious in 1.2% vs 1.7% 
- Worsening renal function (sustained eGFR reduction >50%, ESRD [eGFR <15 >28 days], or death from renal disease): 1.2% vs 1.6% 
- Amputations: 0.5% in both groups 
- Fournier’s gangrene: 0 vs <0.1% 
- Bone fractures: 2.1% in both groups 
- Major hypoglycemia: 0.2% in both groups 
- DKA: 0.1% vs 0 
Lab changes (difference vs placebo)
- Weight -0.9 kg, SBP -1.3 mm Hg 
- NT-proBNP -303 pg/mL 
- HbA1c -0.24% 
- SCr +1.8 umol/L 
Internal validity: Low risk of allocation, performance, detection & attrition bias
- Computer-generated randomization, stratified by presence of type 2 diabetes 
- Allocation concealed by interactive voice/web-response system 
- Participants, clinicians unaware of treatment assignment (blinded) 
- Blinded adjudication of outcomes 
- Loss-to-follow-up <0.8% 
- Analysis of the intention-to-treat (ITT) population 
Other trial of dapagliflozin in HFrEF: DEFINE-HF (PMID: 31524498)
- Participants (n=263) - Included: HF with LVEF 40% or less, NYHA 2-3, elevated natriuretic peptide (NT-proBNP 400+ pg/mL or BNP 100+ pg/mL), +/- T2DM 
- Excluded: Type 1 diabetes, HF hospitalization within last 30 days, eGFR <30 
- Baseline characteristics: - 61 y/o, male 73%, white 55%/black 40% 
- ischemic etiology 53%, prior HF hospitalization ~80%, HF duration 7 years 
- NYHA 2 (70%), 3 (30%), KCCQ overall summary score 67/100 
- LVEF 26% 
- T2DM 62%, AF 40% 
- SBP 123, HR 72, eGFR 65-70, HbA1c ~7% 
- Meds: ACEI/ARB 60%/ARNI 30%, BB 95-100%, MRA 60%, ICD 60%, CRT 20-30% 
 
 
- Dapagliflozin 10 mg/d (intervention) vs placebo (control) 
- Outcomes @ 12 weeks: - QoL measured using KCCQ overall summary score - Mean 3-point improvement with dapagliflozin vs placebo 
- Improvement of 5+ points: Dapagliflozin 43% vs placebo 33% (NNT 10) 
- Difference in KCCQ sub-domains of clinical summary score, total symptom score, physical limitation score & QoL score, but not social limitation score 
 
- No difference between dapagliflozin vs placebo in: - Change in NT-proBNP 
- Any adverse effects 
 
 
- Internal validity: Low risk of bias. 
