Study Background and Disease Burden
Hypertension remains a leading global cause of cardiovascular morbidity and mortality. A significant subset of patients exhibits uncontrolled or resistant hypertension, defined as blood pressure that remains above target despite adherence to multiple antihypertensive agents, including diuretics. Aldosterone, a mineralocorticoid hormone, is implicated in the pathogenesis of difficult-to-control hypertension through mechanisms involving sodium retention, vascular remodeling, and sympathetic activation. Aldosterone synthase inhibitors, such as baxdrostat, target aldosterone biosynthesis to potentially improve blood pressure control in these challenging populations. Previous smaller studies demonstrated that baxdrostat effectively lowers seated systolic blood pressure in patients with uncontrolled or resistant hypertension, addressing a critical unmet medical need in cardiovascular therapeutics.
Study Design
This report concerns a pivotal phase 3, multinational, double-blind, randomized, placebo-controlled trial involving adult patients with uncontrolled hypertension (seated systolic blood pressure 140 to <170 mm Hg on two stable antihypertensive medications) or resistant hypertension (on three or more medications including a diuretic). Following a 2-week placebo run-in period, patients with a seated systolic blood pressure of 135 mm Hg or higher were randomized in a 1:1:1 ratio to receive either baxdrostat 1 mg, baxdrostat 2 mg, or placebo once daily for 12 weeks, alongside their background therapies. The primary endpoint was the change in seated systolic blood pressure from baseline to week 12.
Key Findings
A total of 796 patients were randomized, with 794 receiving study drug or placebo: 264 patients received 1 mg baxdrostat, 266 patients 2 mg baxdrostat, and 264 patients placebo. After 12 weeks, the least-squares mean reduction in seated systolic blood pressure was -14.5 mm Hg (95% CI, -16.5 to -12.5) for 1 mg baxdrostat, -15.7 mm Hg (95% CI, -17.6 to -13.7) for 2 mg baxdrostat, and -5.8 mm Hg (95% CI, -7.9 to -3.8) for placebo. The placebo-corrected differences were statistically significant: -8.7 mm Hg (95% CI, -11.5 to -5.8) for 1 mg and -9.8 mm Hg (95% CI, -12.6 to -7.0) for 2 mg (P6.0 mmol/L) occurred in 2.3% of patients on 1 mg baxdrostat and 3.0% on 2 mg baxdrostat, compared to 0.4% on placebo. These events were infrequent but highlight the need for potassium monitoring, consistent with the drug’s mechanism inhibiting aldosterone-mediated potassium excretion. Overall, baxdrostat was well tolerated with no new safety signals.
Expert Commentary
The BaxHTN trial furnishes compelling evidence that baxdrostat, by selectively inhibiting aldosterone synthase, substantially lowers seated systolic blood pressure in patients with uncontrolled or resistant hypertension beyond standard background therapy. This magnitude of blood pressure reduction has the potential to translate into clinically meaningful cardiovascular risk reduction, although longer-term outcome data are awaited.
Compared with mineralocorticoid receptor antagonists (MRAs) such as spironolactone, baxdrostat offers a mechanistically distinct approach by inhibiting aldosterone synthesis rather than receptor blockade, which may convey advantages in side effect profiles, as MRAs are associated with hormonal adverse effects like gynecomastia. However, the risk of hyperkalemia remains a class concern due to altered potassium homeostasis.
Limitations of the study include the relatively short duration (12 weeks), which precludes assessment of long-term cardiovascular outcomes and sustained safety. Furthermore, the trial included patients already on optimized therapies including diuretics, which may limit generalizability to broader hypertensive populations. Future studies should examine long-term efficacy, cardiovascular event reduction, and comparative effectiveness versus established agents.
Conclusion
Baxdrostat represents a promising novel therapeutic option for patients with uncontrolled or resistant hypertension, effectively reducing seated systolic blood pressure when added to standard antihypertensive medications. Its safety profile is acceptable, with manageable hyperkalemia risk. Integration of baxdrostat into hypertension management paradigms could potentially address a significant unmet clinical need. Continued surveillance through post-marketing studies and further research are warranted to delineate its role in cardiovascular risk reduction and to optimize patient selection.
References
Flack JM, Azizi M, Brown JM, Dwyer JP, Fronczek J, Jones ESW, Olsson DS, Perl S, Shibata H, Wang JG, Wilderäng U, Wittes J, Williams B; BaxHTN Investigators. Efficacy and Safety of Baxdrostat in Uncontrolled and Resistant Hypertension. N Engl J Med. 2025 Aug 30:10.1056/NEJMoa2507109. doi: 10.1056/NEJMoa2507109. Epub ahead of print. PMID: 40888730; PMCID: PMC7618089.
Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/AphA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. Hypertension. 2018;71(6):e13-e115.
Calhoun DA, et al. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association. Hypertension. 2008;51(6):1403-19.
