IntroductionThe angiotensin receptor neprilysin inhibitor (ARNI) sacubitril/valsartan (SAC/VAL) has shown benefit in patients with symptomatic heart failure (HF), including those naïve to renin–angiotensin–aldosterone system inhibitor (RAASi) therapy, and is considered the preferred RAASi for chronic HF. Real-world data on ARNI, specifically in RAASi-naïve patients, are limited. This study compared real-world outcomes of ARNI (SAC/VAL) vs. angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) therapy in RAASi-naïve patients with HF and reduced ejection fraction (HFrEF).MethodsThis retrospective cohort study included de-identified data on RAASi-naïve patients with HFrEF (left ventricular ejection fraction ≤ 40%) who had newly initiated SAC/VAL or ACEi/ARB between July 1, 2015, and March 31, 2019, from the Optum® Electronic Health Records database in the US. New SAC/VAL users were propensity score matched 1:2 with new ACEi/ARB users by pre-selected characteristics. One-year post-index rates of all-cause, HF, and cardiovascular hospitalizations and the composite of HF hospitalization or emergency room (ER) visits were measured using negative binomial regression. Time to first all-cause hospitalization, HF hospitalization, and composite of HF hospitalization or ER visits was measured using a subdistribution hazards model.ResultsThe matched sample included 3059 new SAC/VAL and 6118 new ACEi/ARB users. Rates of all-cause hospitalization and composite of HF hospitalization or ER visits were significantly lower with SAC/VAL compared with ACEi/ARB (incidence rate ratio [95% confidence interval]: 0.87 [0.81–0.93] and 0.87 [0.81–0.94], respectively), whereas rates of HF hospitalizations and cardiovascular hospitalizations were similar (1.00 [0.91–1.11] and 0.94 [0.87–1.02], respectively). Time-to-event analyses also showed a similar trend.ConclusionsIn real-world clinical practice, RAASi-naïve patients with HFrEF initiating SAC/VAL were less likely to be hospitalized than those initiating ACEi/ARB, suggesting a potential for a reduced clinical and economic burden in these patients.