The initial large clinical trials were focused on patients with type 2 diabetes, the main inclusion criterion.
The EMPA-REG OUTCOME trial was the earliest SGLT2i cardiovascular outcome trial and showed major cardiovascular benefits
[4]. The trial studied 7020 patients with type 2 diabetes and patients received either empagliflozin or placebo. There was a reduction in major adverse cardiovascular events (MACE) (myocardial infarction, stroke, cardiovascular death) in the empagliflozin group (HR, 0.86; 95% CI, 0.74–0.99;
p = 0.04 for superiority). Additionally, a reduction in hospitalization for heart failure was observed in patients receiving empagliflozin (HR, 0.65; 95% CI, 0.50–0.85;
p = 0.002). This trial was the first positive cardiovascular outcome trial in type 2 diabetics.
The CANVAS Program trial compared canagliflozin to placebo in 10,142 patients with type 2 diabetes. A reduction in major adverse cardiovascular event was observed in the canagliflozin group (HR, 0.86; 95% CI, 0.75–0.97;
p = 0.02 for superiority)
[5][6]. Additionally, hospitalization for heart failure and cardiovascular death was reduced in the canagliflozin group (HR 0.78; 95% CI, 0.67–0.91). There was an increased risk of amputation, specifically at the toe or metatarsal in those that received canagliflozin.
The DECLARE-TIMI 58 trial evaluated dapagliflozin compared to placebo in 17,160 patients with type 2 diabetes
[7][8]. There was a reduction in heart failure-related death and hospitalization (HR, 0.83; 95% CI, 0.73–0.95;
p = 0.005). Notably, dapagliflozin did not reduce the rate of major adverse cardiovascular event (HR, 0.93; 95% CI, 0.84–1.03;
p = 0.17). Renal events occurred less frequently in the dapagliflozin group (HR, 0.76; 95% CI, 0.67 to 0.87).
The TIMI Study Group performed a meta-analysis which included the EMPA-REG OUTCOME, CANVAS Program, and DECLARE-TIMI 58 trials with a total of 34,322 patients
[9]. SGLT2i reduced hospitalization for heart failure (HR, 0.77; 95% CI 0.71–0.84;
p < 0.0001) and progression of renal disease (HR, 0.55; 95% CI 0.48–0.64,
p < 0.0001) in patients with or without cardiovascular disease or history of heart failure.
These trials showed the benefits of SGLT2i in reducing cardiovascular events in patients with type 2 diabetes (Table 1). This led to trials focusing on primarily examining cardiovascular benefits.
3. Sodium Glucose Cotransporter 2 Inhibitor Trials in Cardiovascular Disease
After observing such major cardiovascular benefits from SGLT2i in patients with type 2 diabetes, researchers decided to evaluate the potential cardiovascular benefits from SGLT2i therapy in patients without type 2 diabetes.
The DAPA-HF trial included 4744 heart failure reduced ejection fraction (HFrEF) patients receiving dapagliflozin versus placebo
[12]. Dapagliflozin reduced the occurrence of the composite outcome of worsening heart failure or cardiovascular mortality (HR, 0.74; 95% CI 0.65–0.85;
p < 0.001). Additionally, both hospitalization for heart failure (HR, 0.70; 95% CI 0.59–0.83) and cardiovascular mortality (HR, 0.82; 95% CI, 0.69–0.98) were reduced by dapagliflozin regardless of diabetic status.
The EMPEROR-Reduced trial compared empagliflozin to placebo in 3730 HFrEF patients
[13]. The primary composite outcome of hospitalization for heart failure or cardiovascular death was reduced by empagliflozin (HR, 0.75; 95% CI, 0.65–0.86;
p < 0.001). Empagliflozin reduced the number of hospitalizations for heart failure (HR, 0.70; 95% CI, 0.58–0.85;
p < 0.001). The benefits of empagliflozin in reducing cardiovascular death and worsening heart failure was observed regardless of diabetic status.
The EMPEROR-Preserved trial compared empagliflozin to placebo in 5988 patients with heart failure with preserved ejection fraction (HFpEF) (ejection fraction above 40%)
[14]. The primary outcome of hospitalization for heart failure or cardiovascular death was reduced by empagliflozin (HR, 0.79; 95% CI 0.69–0.90;
p < 0.001) in both patients with or without diabetes. This result was mainly driven by the lowered risk of hospitalization for heart failure in those receiving empagliflozin.
The SOLOIST-WHF trial evaluated sotagliflozin and placebo in 1222 patients hospitalized for worsening heart failure, which included both HFrEF and HFpEF patients
[15]. Interestingly, sotagliflozin is both a sodium glucose cotransporter 2 (SGLT2) inhibitor and sodium glucose cotransporter 1 (SGLT1) inhibitor. Sotagliflozin reduced cardiovascular death and hospitalization (HR, 0.67; 95% CI, 0.52–0.85;
p < 0.001). This trial demonstrated that SGLT2i therapy can be started safely and effectively in patients even after an episode of decompensation
[16]. Initiation of sotagliflozin before or after discharge significantly lowered cardiovascular death and urgent visits for heart failure.
The EMPULSE trial included 530 hospitalized patients with diagnosis of acute de novo or decompensated chronic heart failure regardless of left ventricular ejection fraction
[17]. Patients were randomized to receive either empagliflozin or placebo. The primary outcome was a composite of death, number of heart failure events, time to first heart failure event, or a 5-point or greater change in the Kansas City Cardiomyopathy Questionnaire Total Symptom Score. Patients that received empagliflozin experienced greater benefit compared to the placebo group (stratified win ratio, 1.36; 95% CI, 1.09–1.68;
p = 0.0054). The effectiveness of empagliflozin was observed in both acute de nove and decompensated chronic heart failure, regardless of ejection fraction or diabetic status. These clinical benefits could be observed in the 90 days after treatment initiation. The EMPULSE trial demonstrated that empagliflozin can be safely initiated in hospitalized patients for acute heart failure.
The DELIVER trial studied the role of dapagliflozin compared to placebo in 6263 heart failure patients
[18]. This trial is the most inclusive heart failure trial. Namely, the trial included both hospitalized patients and outpatients with an ejection fraction of 40% or greater or an improved ejection fraction (previously EF < 40%). Dapagliflozin was shown to reduce the primary composite endpoint of cardiovascular death or worsening heart failure (HR, 0.82; 95% CI 0.73–0.92;
p < 0.001). Those receiving dapagliflozin experienced lower total events and symptoms compared to the placebo group.
A pooled meta-analysis of the DAPA-HF and DELIVER trials demonstrated that dapagliflozin reduced the risk of cardiovascular death (HR, 0.86; 95% CI 0.76–0.97;
p = 0.01), hospitalization for heart failure (RR, 0.71; 95% CI 0.65–0.78;
p < 0.001), and major adverse cardiovascular event (HR, 0.90; 95% CI 0.81–1.00;
p = 0.045), across a whole spectrum of left ventricular ejection fractions from ejection fraction of 25% to 65%
[19]. This has widened the indications for SGLT2i.
These SGLT2i cardiovascular trials show the effective reduction of hospitalization for heart failure and cardiovascular death (Table 2). SGLT2i indications for cardiovascular disease continue to expand with subsequent cardiovascular outcome trial.
Table 2. SGLT2i trials in cardiovascular disease.
Trial (Medication) |
Main Outcome HR (95% CI) (p-Value) |
Key Summary |
DAPA-HF [12] (dapagliflozin 10 mg) |
↓ composite of CV death and HHF 0.74 (0.65–0.85) (p < 0.001) |
Dapagliflozin reduced the risk of worsening HF or CV death in HFrEF patients, regardless of diabetic status. |
EMPEROR-Reduced [13] (empagliflozin 10 mg) |
↓ composite of CV death and HHF 0.75 (0.65–0.86) (p < 0.001) |
Empagliflozin shown to reduce HHF and CV death in HFrEF, regardless of diabetic status. |
EMPEROR-Preserved [14] (empagliflozin 10 mg) |
↓ CV death or HHF 0.79 (0.69–0.90) (p < 0.001) |
Empagliflozin reduced CV death or HHF in HFpEF patients. |
SOLOIST-WHF [15] (sotagliflozin 200 or 400 mg) |
↓ CV death and HHF 0.67 (0.52–0.85) (p < 0.001) |
This was the first major trial of SGLT1/SGLT2 inhibitor in hospitalized patients. |
EMPULSE [17] (empagliflozin 10 mg) |
↓Death, HF events, time to first HF event, ≥5 change in KCCQ score stratified win ratio, 1.36 (1.09–1.68) (p = 0.0054) |
Empagliflozin is effective and can be safely initiated in hospitalized patients. |
DELIVER [18]/Meta-analysis of DELIVER and DAPA-HF [19] (dapagliflozin 10 mg) |
↓ CV death or worsening HF 0.82 (0.73–0.92) (p < 0.001) |
Patients with HF with mildly reduced or preserved ejection fraction. Dapagliflozin benefits extend to all HF patients across a whole spectrum of EF. |