Background: Sacubitril-valsartan is an angiotensin receptor-neprilysin inhibitor (ARNI) that is now preferred over angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin-II-receptor blockers (ARBs) for treating heart failure with reduced ejection fraction (HFrEF). Primary medication adherence to a costly brand-name ARNI, compared to inexpensive generic ACE-Is or ARBs, is unknown.
Methods: This cohort study used a linked database of electronic health records and Medicare fee-for-service claims from a large integrated health care system in Boston to compare primary medication adherence among Medicare beneficiaries with HFrEF newly prescribed sacubitril-valsartan, those newly prescribed a generic ACE-I or ARB, and those switching from an ACE-I or ARB to sacubitril-valsartan. The primary outcome was the proportion of individuals who filled their first prescription for any ARNI, ACE-I, or ARB within 90 days; a secondary outcome was the mean number of days to first fill. We used logistic regression to adjust for variations in patient characteristics, including demographics, comorbidities, medication use, and qualification for subsidized out-of-pocket prescription drug costs.
Results: Among 50 new sacubitril-valsartan prescription recipients, 33 (66%) demonstrated primary adherence at 90 days, compared to 141 of 231 (61%) new ACE-I or ARB prescription recipients (adjusted odds ratio 1.32, 95% CI, 0.63-2.73, P = .51). The mean time to first fill was 18 days for those prescribed sacubitril-valsartan and 9 days for those prescribed generic ACE-Is or ARBs (P < .001). By contrast, primary adherence at 90 days was higher (329 of 364, 90%) among those who switched from a generic ACE-I or ARB to newly prescribed sacubitril-valsartan.
Conclusions: In this small, single-center cohort study of Medicare beneficiaries with HFrEF, there was no difference in primary medication adherence among individuals newly prescribed sacubitril-valsartan and those newly prescribed generic ACE-Is or ARBs, although it took sacubitril-valsartan prescription recipients longer to fill their medication. Adherence was high among patients switching from an ACE-I or ARB to sacubitril-valsartan, suggesting that this switch was not associated with interruptions in renin-angiotensin blockade.
Published by Elsevier Inc.