Targeting Aldosterone at Its Source: The Arrival of Baxdrostat for Resistant Hypertension

Hypertension remains one of the leading modifiable risk factors for cardiovascular disease worldwide. Despite the availability of numerous antihypertensive agents, many patients fail to achieve adequate blood pressure control, particularly those with resistant hypertension. Resistant hypertension is generally defined as uncontrolled blood pressure despite treatment with 3 or more antihypertensive medications of different classes, including a diuretic.¹ The recent approval of baxdrostat (Baxfendy; AstraZeneca) introduces a novel therapeutic approach that targets aldosterone production, a key driver of hypertension and cardiovascular risk.²

Understanding the Role of Aldosterone

Aldosterone is a mineralocorticoid hormone produced by the adrenal cortex that regulates sodium retention, fluid balance, and potassium excretion. Excess aldosterone activity contributes to hypertension, vascular inflammation, cardiac remodeling, and chronic kidney disease.³ Emerging evidence suggests that aldosterone excess may be more prevalent in resistant hypertension than previously recognized, making it an attractive therapeutic target.¹^,³

Mechanism of Action

Baxdrostat is a highly selective aldosterone synthase inhibitor that blocks CYP11B2, the enzyme responsible for the final step in aldosterone biosynthesis.² By inhibiting aldosterone production at its source, baxdrostat reduces sodium and water retention, ultimately lowering blood pressure. Unlike spironolactone and eplerenone, which block the mineralocorticoid receptor after aldosterone is produced, baxdrostat prevents excessive aldosterone formation altogether.²^,⁴ Importantly, baxdrostat demonstrates high selectivity for CYP11B2 while minimizing inhibition of CYP11B1, the enzyme involved in cortisol synthesis. This selectivity may reduce the risk of cortisol-related adverse effects observed with less selective steroidogenesis inhibitors.²

Clinical Evidence Supporting Baxdrostat

The phase 2 BrigHTN trial (NCT04519658) evaluated baxdrostat in patients with treatment-resistant hypertension receiving standard antihypertensive therapy. Patients treated with baxdrostat experienced significant reductions in systolic blood pressure compared with placebo, with greater reductions observed at higher doses.² Furthermore, treatment resulted in substantial decreases in plasma aldosterone concentrations, confirming successful target engagement.² These findings established proof-of-concept for aldosterone synthase inhibition and supported continued clinical development. Additional studies demonstrated sustained blood pressure reductions and an acceptable safety profile, ultimately contributing to regulatory approval.⁴

Advantages of a First-in-Class Therapy

Potential advantages of baxdrostat include the following²^,⁴:

• Direct inhibition of aldosterone production
• Novel treatment option for resistant hypertension
• Potential utility in patients with aldosterone-driven disease
• Reduced reliance on escalating doses of existing antihypertensive therapies
• Expansion of precision medicine approaches in cardiovascular care

Considerations for Pharmacists

Pharmacists play a critical role in ensuring the safe and effective use of baxdrostat. Monitoring should include blood pressure, serum potassium concentrations, and renal function.²^,⁴ Because suppression of aldosterone may increase potassium levels, patients should be counseled regarding the signs and symptoms of hyperkalemia and potential drug interactions with other potassium-elevating agents.⁴ Additionally, pharmacists should reinforce adherence to lifestyle modifications, including sodium restriction, weight management, and regular physical activity, as part of a comprehensive hypertension management plan.¹

Future Implications

The approval of baxdrostat represents one of the most significant advancements in hypertension treatment in recent years. By targeting aldosterone synthesis directly, baxdrostat offers a novel mechanism for addressing resistant hypertension and highlights the growing role of precision medicine in cardiovascular disease management. Ongoing research will further clarify its long-term effects on cardiovascular and renal outcomes, potentially expanding its role beyond blood pressure reduction.³^,⁴

References

1. Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. Hypertension. 2018;71(6):e13-e115. doi:10.1161/HYP.0000000000000065

2. Fisher NDL, Williams B, Dawson J, et al. Baxdrostat for treatment-resistant hypertension. N Engl J Med. 2023;388(5):395-405. doi:10.1056/NEJMoa2213169

3. Hundemer GL, Vaidya A. Aldosterone excess and resistant hypertension: emerging concepts and therapeutic opportunities. Hypertension. 2024;81(2):e20-e31.

4. Baxfendy (baxdrostat) Prescribing information. AstraZeneca; 2026.