Estimation of Out-of-Pocket Costs for Guideline-Directed Medical Therapy for Heart Failure Under Medicare Part D and the Inflation Reduction Act

Abstract

This cross-sectional study estimates out-of-pocket costs of heart failure with reduced ejection fraction medication regimens in Medicare Part D under current law and the Inflation Reduction Act.

Guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) is effective in reducing mortality, but high out-of-pocket (OOP) costs may act as a barrier to use given the inclusion of brand-name drugs in guideline-recommended regimens (angiotensin receptor-neprilysin inhibitor [ARNI] and sodium-glucose cotransporter 2 inhibitor [SGLT2i]).^1,2,3 The Inflation Reduction Act (IRA), signed into law in August 2022, aims to alleviate OOP costs for Medicare beneficiaries by adding a $2000 cap on annual OOP spending and by reforming the structure of the Medicare Part D benefit. In this cross-sectional study, we estimated OOP costs of HFrEF medication regimens in Part D under current law and the IRA.

Methods

The study did not require institutional review board review because we exclusively used publicly available deidentified data. The study followed the STROBE reporting guideline.

Medication regimens were constructed based on 2022 society guidelines.² List prices were determined using the Part D Plan Finder in February 2022. Out-of-pocket costs were estimated using fourth-quarter 2021 Part D formulary files and summed across each benefit phase (eg, deductible, initial coverage, coverage gap, catastrophic), stratified by plans using copayments (fixed dollar amount) vs coinsurance (percentage of list price) in the initial coverage phase. The base analysis included the medication in each class most prescribed to Medicare beneficiaries (using the 2020 Part D Dashboard) and modeled a beneficiary without subsidies who faced the standard deductible and had no other drug spending. The IRA was modeled as if the law’s provisions were in full effect in 2022. We analyzed data using SAS Studio version 3.8 (SAS Institute Inc).

Results

For 6 medication regimens, among Part D plans using copayments, annual OOP costs under current law were $482 for metoprolol succinate, lisinopril, and spironolactone (all generics); $1518 for metoprolol succinate, lisinopril, spironolactone, and empagliflozin (generics plus SGLT2i); $1917 for metoprolol succinate, sacubitril/valsartan, and spironolactone (generics plus ARNI); and $2644 to $2849 for metoprolol succinate or carvedilol, sacubitril/valsartan, spironolactone or eplerenone, and empagliflozin or dapagliflozin (Table).

Table. Estimated Medicare Part D OOP Costs for Select Guideline-Directed Medical Therapy Regimens Under Current Law and the Inflation Reduction Act of 2022^a.

Medication regimen	Description	Cost, $
		List price, monthly	Expected annual OOP spending
			Plans with copayments		Plans with coinsurance
			Current law	IRA	Current law	IRA
Metoprolol succinate, lisinopril, spironolactone	Generics only	44	482	482	492	492
Metoprolol succinate, lisinopril, spironolactone, empagliflozin	Generics + SGLT2i	614	1518	1007	2203	2000
Metoprolol succinate, sacubitril/valsartan, spironolactone	Generics + ARNI	768	1917	1015	2663	2000
Metoprolol succinate, sacubitril/valsartan, spironolactone, empagliflozin	Comprehensive therapy	1338	2659	1551	3224	2000
Carvedilol, sacubitril/valsartan, spironolactone, empagliflozin	Comprehensive therapy, lowest cost	1314	2644	1527	3210	2000
Metoprolol succinate, sacubitril/valsartan, eplerenone, dapagliflozin	Comprehensive therapy, highest cost	1546	2849	2000	3349	2000

Abbreviations: ARNI, angiotensin receptor-neprilysin inhibitor; IRA, Inflation Reduction Act; OOP, out of pocket; SGLT2i, sodium-glucose cotransporter 2 inhibitor.

^a Estimated prices were calculated using the fourth-quarter 2021 Medicare Part D plan formulary files. List prices were identified in February 2022 from the Part D Plan Finder for zip code 37203 for an in-area pharmacy. For specified regimens in 2022, over 90% of plans used a copayment during the initial coverage phase. For annual spending under current law, we applied a $480 deductible, either the median copayment or 25% coinsurance for each drug filled in the initial coverage phase (until total drug spending reached $4430), 25% coinsurance during the coverage gap (until total drug spending reached $10 690), and 5% coinsurance in the catastrophic coverage phase. For annual spending under the IRA, we applied a $480 deductible and either the monthly median copayment or 25% coinsurance for each month until a beneficiary had spent $2000 out-of-pocket. We assumed $0 thereafter.

Under current law, users of comprehensive therapy (metoprolol succinate, sacubitril/valsartan, spironolactone, and empagliflozin) would meet their deductible in January, enter the coverage gap in April, and reach the catastrophic phase in September (Figure, A). Under the IRA and a Part D plan using copayments in the coverage phase, beneficiaries would meet their deductible in January and pay flat copayments for the remainder of the year, never reaching the catastrophic cap (Figure, A). Under the IRA and a plan using coinsurance, beneficiaries would reach the $2000 cap in May and have no OOP costs thereafter (Figure, B).

Figure. Estimated Medicare Part D Monthly Out-of-Pocket Costs for Metoprolol Succinate, Sacubitril/Valsartan, Spironolactone, and Empagliflozin.

Discussion

Guideline-recommended medication regimens for HFrEF currently have annual OOP costs above $2500 under Medicare Part D. These costs are based primarily on the high prices of 2 on-patent medications (ARNI and SGLT2i), the use of multiple medications, and the Part D coinsurance requirement in the coverage gap under current law. Given that GDMT reduces mortality, it is possible that high OOP costs for GDMT reduce use of these drugs and potentially increase mortality.⁴

A limitation of this study is our assumption of no other medication use when calculating OOP costs. The IRA is estimated to reduce OOP costs for GDMT, both by limiting annual OOP spending to $2000 and by reforming the Part D benefit to eliminate the coverage gap. The IRA will decrease OOP costs for many beneficiaries who do not reach the annual cap, assuming plans continue to use copayments under the redesigned benefit. The reduction in OOP expenses may be greater for the patients with HFrEF receiving additional costly medications for comorbid conditions. The IRA also allows beneficiaries to opt into a program to smooth OOP costs over the year, which could further improve affordability of HFrEF regimens. Our findings suggest that the IRA may decrease OOP costs and may increase the use of lifesaving heart failure medications by Medicare beneficiaries.

Supplement.

Data Sharing Statement