Series: Landmark Trials in Endocrinology & Metabolism | Study #7
Category: SGLT2 Inhibitors · Renal Protection | Design: Multicentre, double-blind, placebo-controlled RCT | n: 4,304 | Follow-up: 2.4 years (median; stopped early)
📋 Summary
Authors: Heerspink HJL et al., for the DAPA-CKD Trial Committees and Investigators
Journal: N Engl J Med 2020;383:1436–1446 | DOI: 10.1056/NEJMoa2024816
DAPA-CKD enrolled 4,304 patients with chronic kidney disease defined by an estimated glomerular filtration rate (eGFR) of 25 to 75 ml/min/1.73 m² and a urinary albumin-to-creatinine ratio of 200 to 5,000 mg/g, on stable maximum tolerated doses of renin-angiotensin system blockade. Crucially, 32.5% of participants did not have type 2 diabetes, making this the first SGLT2 inhibitor renal outcomes trial to include a substantial non-diabetic CKD population. Patients were randomly assigned to dapagliflozin 10 mg once daily or placebo. The primary composite outcome comprised a sustained decline of 50% or more in eGFR, end-stage kidney disease (ESKD), or death from a renal or cardiovascular cause. The trial was stopped early after a planned interim analysis demonstrated clear superiority. At the time of stopping, the primary outcome had occurred in 9.2% of patients in the dapagliflozin group and 14.5% in the placebo group (HR 0.61; 95% CI 0.51 to 0.72; p<0.001), a 39% relative risk reduction. The kidney-specific composite of a 50% or greater eGFR decline, ESKD, or renal death was reduced by 44% (HR 0.56; 95% CI 0.45 to 0.68). The composite of cardiovascular death or heart failure hospitalisation was reduced by 29% (HR 0.71; 95% CI 0.55 to 0.92), and all-cause mortality was reduced by 31% (HR 0.69; 95% CI 0.53 to 0.88). The treatment effect on the primary outcome was consistent in patients with and without type 2 diabetes, an observation with far-reaching implications for the management of non-diabetic CKD.
📊 Key Findings
| Outcome | Dapagliflozin | Placebo | Effect Size |
|---|---|---|---|
| Primary composite (≥50% eGFR decline, ESKD, or renal/CV death) | 9.2% | 14.5% | HR 0.61 (0.51–0.72) · p<0.001 · 39% RRR |
| Kidney-specific composite (≥50% eGFR decline, ESKD, renal death) | — | — | HR 0.56 (0.45–0.68) · 44% RRR |
| CV death or HF hospitalisation | — | — | HR 0.71 (0.55–0.92) |
| All-cause mortality | — | — | HR 0.69 (0.53–0.88) |
| Benefit in T2DM subgroup | Consistent with overall | HR 0.64 (0.52–0.79) | |
| Benefit in non-T2DM subgroup | Consistent with overall | HR 0.50 (0.35–0.72) | |
| Absolute risk reduction (primary composite) | ~5.3% over 2.4 years | NNT approximately 19 | |
💬 Expert Commentary
DAPA-CKD expanded the nephroprotective evidence for SGLT2 inhibition beyond the diabetic nephropathy context established by CREDENCE into the much broader category of albuminuric CKD of any aetiology. The inclusion of approximately one third of participants without diabetes is the defining feature of the trial’s contribution. Prior to DAPA-CKD, the management of non-diabetic CKD with proteinuria had not seen a major pharmacological advance beyond RAS blockade in over two decades. The observation that dapagliflozin reduced the kidney-specific composite by 44% in non-diabetic CKD, with an HR of 0.50 that is numerically more favourable than in the diabetic subgroup, suggests that the renal haemodynamic mechanism, primarily tubuloglomerular feedback restoration and reduction of intraglomerular hypertension, operates independently of and additive to the downstream effects of glucose lowering. This finding has since been reinforced by the FLOW trial with semaglutide, but DAPA-CKD was the first to make the case for a class effect applicable to CKD irrespective of diabetic status.
The mortality reduction of 31% (HR 0.69; 0.53–0.88) is particularly striking for a renal outcomes trial and reflects the well-established association between CKD progression and cardiovascular mortality in this population. The reduction in the cardiovascular composite of death or heart failure hospitalisation provides further confirmation that the cardiorenal effects of SGLT2 inhibition operate in both directions, protecting the kidney from cardiovascular stress and reducing cardiovascular risk through renal haemodynamic effects. Together with CREDENCE, DAPA-CKD formed the evidence base for international CKD guidelines recommending SGLT2 inhibitors in all patients with CKD and albuminuria, regardless of diabetes diagnosis, who have an eGFR above approximately 20 ml/min/1.73 m².
Limitations: The trial was stopped early, which may have led to an overestimate of the treatment effect. Patients with eGFR below 25 ml/min/1.73 m² were excluded, limiting evidence in advanced CKD. Non-diabetic CKD diagnoses were heterogeneous and not confirmed by biopsy in most cases. The study was industry-sponsored by AstraZeneca.
🔑 BOTTOM LINE
DAPA-CKD demonstrated that dapagliflozin reduces kidney failure, cardiovascular death, and all-cause mortality by approximately 39–44% in patients with albuminuric CKD on background RAS blockade, with consistent benefit in both diabetic and non-diabetic CKD, fundamentally broadening the indication for SGLT2 inhibition from diabetic nephropathy to albuminuric CKD of any cause.
⭐ Clinical Impact Rating: ●●●●● Practice-defining
Next in the series: Study #8 LEADER: Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes
