The DAPA-HF trial found that among patients with heart failure and reduced ejection fraction, those who received the SGLT2 inhibitor dapagliflozin had a lower risk of hospitalization for heart failure or cardiovascular death and better symptom scores compared to placebo, regardless of the presence of diabetes. Dapagliflozin reduced the primary composite outcome of worsening heart failure or cardiovascular death across subgroups. It provided cardiovascular benefits in patients without diabetes. Adverse effects were generally uncommon and less frequent with dapagliflozin.