MRAs for reduced ejection fraction

HFrEF roles, mechanism and applicability

Spironolactone and eplerenone block the mineralocorticoid receptor. The 2022 US guideline recommends either for symptomatic HFrEF NYHA II–IV when eGFR >30 mL/min/1.73 m² and potassium <5.0 mmol/L, with monitoring; discontinue if potassium cannot be maintained below 5.5. The eplerenone US indication specifically covers stable symptomatic HFrEF after acute MI; guideline-supported chronic HFrEF use is broader. Finerenone has an HF label for EF ≥40% and a separate CKD/T2D indication; it is not established as a replacement for spironolactone/eplerenone in EF <40% HFrEF. At EF exactly 40%, labels overlap, so do not infer a mandatory switch. [1] [2] [3] [6] [5]

RALES studied severe HF with EF ≤35%, mean follow-up 24 months, mostly before routine beta blockers, ARNI or SGLT2 inhibitors. EMPHASIS studied NYHA II, age ≥55, EF ≤30% or 31–35% with QRS >130 ms, median 21 months. Both stopped early for benefit. These are separate placebo-controlled trials on background therapy, not a head-to-head ranking. Absolute differences are crude trial proportions, not individualized forecasts. [1] [2] [3] [6] [5]

Safety and stopping definitions

RALES Table 4: any adverse event 674/822 versus 667/841; gastrointestinal disorders 236/822 versus 241/841, and serious hyperkalemia 14/822 versus 10/841. Breast enlargement or pain uses only men, 603/614; gynecomastia alone was 55/603 versus 8/614. Adverse-event stopping was 62/822 versus 40/841. Serious hyperkalemia requiring discontinuation was 3/822 versus 1/841. Results report 214/200 discontinuations for lack of response, adverse events or administrative reasons, plus a separate 8/11 for transplantation. Do not relabel 214/200 as a death-inclusive all-reasons total. [1] [2] [7]

EMPHASIS safety N=1360/1369 excludes four untreated people per arm. Potassium laboratory subset N=1336/1340; high K >5.5 was 158/96 and >6 was 33/25. Permanent AE withdrawal 188/222 includes permanent hyperkalemia withdrawal 15/12. At cutoff the administration section separately reports drug discontinued in 222/1364 (16.3%) versus 228/1373 (16.6%). Neither equals leaving study follow-up (17/15 lost). Adverse events do not prove drug causation. [1] [2] [7]

The SwedeHF registry analysis of 11,474 new spironolactone/eplerenone users estimates 29% discontinuation at one year by Kaplan–Meier. The 2,944 observed stops must not be divided by 11,474 and labeled 29%. It defined discontinuation using a refill gap beyond estimated supply plus one additional package; a shorter grace period changed the estimate. An estimated 46% restarted within a year of stopping. This is an all-reason dispensing measure, not permanent adverse-effect intolerance, and does not apply to finerenone or HFpEF. [1] [2] [7]

Agent-specific practical label boundaries

Spironolactone: when K ≤5.0 and eGFR >50, usual HF start 25 mg daily; eGFR 30–50 consider 25 mg every other day. Monitor potassium within one week of start/titration and regularly. Hyperkalemia, Addison disease and concomitant eplerenone are contraindications. Renal function, blood pressure and hydration also require follow-up. [4] [5] [3]

Eplerenone: usual post-MI HF start 25 mg daily, target 50 mg daily within four weeks if tolerated; moderate CYP3A inhibitor limits post-MI dose to 25 mg daily. Measure K before treatment, within one week and at one month after start/dose adjustment, then periodically. Label all-use contraindications include K >5.5 at initiation, creatinine clearance ≤30 and strong CYP3A inhibitors; HFrEF guideline initiation uses stricter K <5.0. Hypertension-only contraindications should not be imported wholesale into HF use. [4] [5] [3]

For both, potassium supplements/salt substitutes, NSAIDs, trimethoprim and other potassium-raising drugs require review. Concurrent ACE inhibitor/ARB/ARNI therapy can be intentional but increases monitoring importance. Discuss pregnancy, dehydration and symptoms promptly; serious hyperkalemia may be symptomless, so symptoms cannot replace blood tests. [4] [5] [3]

Price verification and insurance boundaries

All price checks are dated September 5, 2026. GoodRx spironolactone 25 mg, 30 tablets was the standard $9.73 Walgreens coupon for the page default ZIP 85001; its panel says updated August 11, 2026. One tablet daily makes this 30 days. Paid Companion and differently specified teaser prices were excluded. No fully specified accessible eplerenone or finerenone GoodRx quote was verified. [8] [9] [10] [11] [12] [13] [14] [15] [16]

Blueberry public UI: 30 tablets at one daily, nonmember spironolactone 25 mg NDC 59746-0216-09 $11.87 and eplerenone 25 mg NDC 69367-0307-09 $15.69. These include acquisition plus 8% markup, $1.15 supply cost and $10 professional fee. Add $3.99 shipping to obtain $15.86 and $19.68. No verified finerenone result does not establish that the pharmacy cannot supply it. Confirm service area, SKU, tax, current quote and delivery. [8] [9] [10] [11] [12] [13] [14] [15] [16]

KFF 2025 tier copays describe covered workers in employer plans with at least three tiers and copayments; they do not estimate any specific MRA copay. Medicare 2026 standard benefit has a maximum $615 deductible, 25% initial coinsurance and $2,100 annual qualifying out-of-pocket threshold. A plan-negotiated covered $40 fill would imply $10 standard coinsurance only after the deductible and before the cap; this is arithmetic, not a verified MRA price. Plans can differ. Extra Help eligibility and generic/brand caps vary with circumstances; some pay less. Cash coupons used outside Part D do not count toward its deductible or cap. [8] [9] [10] [11] [12] [13] [14] [15] [16]

Finerenone commercial assistance

Bayer advertises as little as $0 per month for eligible commercially insured adults, with maximum annual savings of $3,000. Government-insured patients are excluded and approved-indication and program rules apply. This is an assistance offer, not a cash retail price or typical copay. No enrollment or coverage check was performed. [17]

RALES: Death from any cause

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Primary outcome. Published whole percentages 35%/46%; these displays calculate one decimal from counts. Relative hazard estimate 0.70 (95% CI 0.60–0.82).

Spironolactone: 284/822 (34.5%); Placebo: 386/841 (45.9%). [1]

RALES: At least one HF hospitalization

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Table 2 participant counts. Total repeat HF hospitalizations 413/663 are separate event counts; do not substitute them for participants.

Spironolactone: 215/822 (26.2%); Placebo: 300/841 (35.7%). [1]

RALES: Gynecomastia or breast pain in men

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Men only; combined breast outcome, not gynecomastia alone. Whole published percentages 10%/1%.

Spironolactone: 61/603 (10.1%); Placebo: 9/614 (1.5%). [1]

RALES: Serious hyperkalemia

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Trial-described serious hyperkalemia; no laboratory threshold assigned here. Not all raised potassium results.

Spironolactone: 14/822 (1.7%); Placebo: 10/841 (1.2%). [1]

RALES: Adverse event causing treatment discontinuation

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Table 4 adverse-event discontinuation, not stopping for all reasons and not loss to follow-up. Published whole percentages 8%/5%.

Spironolactone: 62/822 (7.5%); Placebo: 40/841 (4.8%). [1]

RALES: Serious hyperkalemia requiring treatment discontinuation

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Discussion page 713. Paper says discontinuation; no stronger claim that every interruption was permanently irreversible.

Spironolactone: 3/822 (0.4%); Placebo: 1/841 (0.1%). [1]

RALES: Reported treatment discontinuation categories

Severe symptomatic HFrEF, EF ≤35%; randomized N 822/841; Mean 24 months. Results: lack of response, adverse events or administrative reasons. Heart-transplant discontinuations 8/11 reported separately. Do not label 214/200 a death-inclusive all-reasons total.

Spironolactone: 214/822 (26%); Placebo: 200/841 (23.8%). [1]

EMPHASIS-HF: First HF hospitalization or cardiovascular death

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Primary composite; adjusted HR 0.63 (95% CI 0.54–0.74).

Eplerenone: 249/1,364 (18.3%); Placebo: 356/1,373 (25.9%). [2]

EMPHASIS-HF: Death from any cause

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Secondary outcome; HR 0.76 (95% CI 0.62–0.93).

Eplerenone: 171/1,364 (12.5%); Placebo: 213/1,373 (15.5%). [2]

EMPHASIS-HF: Investigator-reported hyperkalemia

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Table 3 treated safety population, not laboratory subset.

Eplerenone: 109/1,360 (8%); Placebo: 50/1,369 (3.7%). [2]

EMPHASIS-HF: Investigator-reported hypotension

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Reported adverse event; not every measured low pressure.

Eplerenone: 46/1,360 (3.4%); Placebo: 37/1,369 (2.7%). [2]

EMPHASIS-HF: Investigator-reported renal failure

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Reported adverse event.

Eplerenone: 38/1,360 (2.8%); Placebo: 41/1,369 (3%). [2]

EMPHASIS-HF: Gynecomastia or other breast disorder

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. All treated participants; unlike RALES male-only denominator.

Eplerenone: 10/1,360 (0.7%); Placebo: 14/1,369 (1%). [2]

EMPHASIS-HF: Potassium >5.5 mmol/L

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Laboratory subset; denominator differs from treated safety set.

Eplerenone: 158/1,336 (11.8%); Placebo: 96/1,340 (7.2%). [2]

EMPHASIS-HF: Potassium >6.0 mmol/L

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Laboratory subset; denominator differs from treated safety set.

Eplerenone: 33/1,336 (2.5%); Placebo: 25/1,340 (1.9%). [2]

EMPHASIS-HF: Permanent withdrawal due to adverse event

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Table 3 treated safety set; not all-reasons withdrawal.

Eplerenone: 188/1,360 (13.8%); Placebo: 222/1,369 (16.2%). [2]

EMPHASIS-HF: Permanent withdrawal due to hyperkalemia

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Subset of permanent adverse-event withdrawal, not additive.

Eplerenone: 15/1,360 (1.1%); Placebo: 12/1,369 (0.9%). [2]

EMPHASIS-HF: Study drug discontinued at trial cutoff

NYHA II HFrEF; EF ≤30%, or 31–35% with prolonged QRS; randomized N 1364/1373; Median 21 months. Study-Drug Administration page 15; randomized denominators reproduce 16.3%/16.6%. Report is a cutoff status, not loss to follow-up or an AE-only rate.

Eplerenone: 222/1,364 (16.3%); Placebo: 228/1,373 (16.6%). [2]

SwedeHF prescription cohort: Refill-defined MRA discontinuation by one year

11,474 new spironolactone/eplerenone users with HFrEF, Sweden 2006–2021; One year. Kaplan–Meier estimate, not 2944/11474. Refill gap beyond estimated supply plus one additional package; includes all reasons and subsequent restarting. No finerenone/HFpEF extrapolation.

Steroidal MRA: 29% estimated by one year; 2,944 observed stops. [7]