The First New Blood Pressure Lowering Mechanism in 20 Years - Aldosterone Synthase Inhibitor Baxdrostat Officially Approved By The FDA For Marketing

On May 18, 2026, the US Food and Drug Administration (FDA) officially approved AstraZeneca's world first aldosterone synthase inhibitor (ASI), baxdrostat (trade name: Baxbendy), for use in combination with other antihypertensive drugs to treat adult hypertensive patients with poor blood pressure control. This is the first antihypertensive drug category with a completely new mechanism of action to officially enter clinical practice in over 20 years, following beta blockers, RAAS inhibitors, and calcium channel blockers.

 

Previously, in February 2026, Baxdrostat's marketing application was officially accepted in China and is currently undergoing review by the National Medical Products Administration (NMPA). It is expected to accelerate the benefits to millions of hypertensive patients with poor blood pressure control in China.

 

 

Hypertension is the primary modifiable risk factor for cardiovascular disease mortality and disability worldwide. However, even under the recommended standard triple or quadruple antihypertensive treatment in various countries' guidelines, a considerable proportion of patients still have blood pressure that cannot meet the standard.

 

A meta-analysis involving over 3.2 million hypertensive patients showed that the prevalence of true refractory hypertension was approximately 10.3% (95% CI 7.6% -13.2%) among those receiving antihypertensive treatment, while the prevalence of apparent refractory hypertension was as high as 14.7%. In the population with concomitant chronic kidney disease, the proportion of refractory hypertension is as high as 22.9%. It is estimated that there are approximately 1.4 billion hypertensive patients worldwide, which means that over 100 million people are facing long-term poor blood pressure control.

 

The reason why refractory hypertension is difficult to control is that aldosterone excess is one of the core mechanisms that is seriously underestimated. Research shows that the prevalence of primary aldosteronism in hypertensive patients may be as high as 5% -10%, and multiple recent studies have shown that its true prevalence may be more than three times higher; However, the current clinical screening rate for this disease is less than 1%. The more widespread "subclinical aldosterone autocrine secretion" exists in a large number of patients with primary hypertension whose blood pressure is difficult to control.

 

 

Baxdrostat is an oral small molecule drug (once a day). By precisely inhibiting aldosterone synthetase (CYP11B2), it blocks the synthesis of adrenal aldosterone from the root, thereby reducing the sodium and water retention in the kidney, reducing blood volume and peripheral vascular resistance, and achieving the goal of lowering blood pressure.

 

Its key technological advantage lies in high selectivity: Baxdrostat has a selectivity for aldosterone synthase (CYP11B2) that is more than 100 times higher than that for cortisol synthase (CYP11B1), significantly reducing aldosterone levels without affecting the normal synthesis of cortisol, thus avoiding the safety hazard of adrenal cortex dysfunction caused by early ASI due to cortisol inhibition.

 

Compared with existing mineralocorticoid receptor antagonists (MRA, such as spironolactone and eplerenone), the mechanism of action of ASI is more upstream: MRA "blocks the gate" (antagonizes aldosterone receptors), while Baxdrostat "shuts off the water source" (inhibits aldosterone synthesis).

 

This essential difference is expected to bring about sex hormone related adverse reactions such as non spironolactone related male breast development, as well as a more controllable risk of hyperkalemia compared to MRA.

 

 

BaxHTN is a multicenter, randomized, double-blind, placebo-controlled trial that enrolled 796 patients with poor blood pressure control on the basis of 2 (including diuretics) or >= 3 antihypertensive drugs. It was simultaneously published in the New England Journal of Medicine in August 2025. The median age of the participants was 62 years old, 39% were female, and 73% belonged to the refractory hypertension subgroup.

 

The main results showed that the Baxdrostat 1 mg group had a 14.5 mmHg decrease in sitting systolic blood pressure compared to baseline and an additional 8.7 mmHg decrease compared to the placebo group; The Baxdrostat 2 mg group showed a 15.7 mmHg decrease in sitting systolic blood pressure compared to baseline and an additional 9.8 mmHg decrease compared to the placebo group. The placebo group had a natural decrease of only 5.8 mmHg.

 

<130 mmHg in the 2 mg group was 40%, nearly twice that of the placebo group (18.7%); Both dose groups achieved statistically significant reductions in diastolic blood pressure; The randomized withdrawal period (8 weeks) confirmed the sustained antihypertensive effect: the SBP of the continued medication group further decreased by 3.7 mmHg, while the placebo group rebounded and increased by 1.4 mmHg (p=0.0016)

Bax24 Phase III Study (published in Lancet, March 2026)

 

To further validate the efficacy of dynamic blood pressure monitoring, the Bax24 study used 24-hour dynamic blood pressure as the primary endpoint and included 217 patients with refractory hypertension (sitting SBP 140-169 mmHg, taking >= 3 antihypertensive drugs including diuretics) from 79 research centers in 22 countries. The results were published in The Lancet in March 2026: The 24-hour dynamic systolic blood pressure of the Saxdrostat 2 mg group decreased by 16.6 mmHg; The placebo adjusted difference was -14.0 mmHg (95% CI -17.2 to -10.8, p<0.0001).

 

71% of Baxdrostat treated patients had a 24-hour dynamic SBP below 130 mmHg, compared to only 17% in the placebo group; The decrease in nighttime systolic blood pressure by 13.9 mmHg (also statistically significant) has important clinical significance in reducing the risk of cardiovascular events related to nighttime hypertension.

 

 

After FDA approval, the international cardiovascular community responded enthusiastically. The official update from the American College of Cardiology (ACC) states that baxdrostat is the first aldosterone synthase inhibitor to enter the US market, marking a new era of precision mechanism intervention in hypertension treatment.

 

The simultaneous review of BaxHTN published by NEJM, jointly written by Professor Tomasz J. Guzik of Glasgow University and Professor Maciej Tomaszewski of Manchester University, clearly pointed out: "If follow-up research can clarify which patients benefit the most, clarify the comparative status with MRA, establish early monitoring norms, and obtain long-term cardiovascular event endpoint data, ASI is expected to change from a promising adjuvant treatment to a core pillar of the treatment system for intractable hypertension, thus promoting a wide revival of natriuresis strategy in the field of blood pressure control.

 

The official website of UCL Biomedical Research Center also emphasizes that Professor Williams evaluates the data of BaxHTN as "an important progress in understanding and treating difficult to control hypertension in the field of blood pressure reduction, bringing hope for more effective treatment", and points out that a decrease in systolic blood pressure of about 10 mmHg is associated with a substantial reduction in the risk of myocardial infarction, stroke, heart failure, and kidney disease.

 

 

Both Phase III studies have confirmed that Baxdrostat has good safety and tolerability, with no occurrence of adrenal insufficiency or severe liver and kidney damage. In the BaxHTN study, the discontinuation rate due to hyperkalemia was 0.8% in the 1 mg group and 1.5% in the 2 mg group; The confirmed incidence of events with blood potassium levels>6 mmol/L in the Bax24 study was 3% (0% in the placebo group).

 

 

For a long time, the treatment options for refractory hypertension have been extremely limited - adding spironolactone to the triple therapy is the "last line of defense", but spironolactone has significant side effects such as male breast development, sexual dysfunction, hyperkalemia, and is not selective for CYP11B1. The launch of Baxdrostat provides a new option with a more upstream mechanism and higher selectivity, which is expected to cover populations with limited application of traditional MRA, such as those with concomitant CKD and high baseline potassium.

 

The NEJM review further points out that the next step of research needs to focus on "which patients are most likely to benefit" - especially patients with a tendency towards primary aldosteronism (PA), CKD patients with hypertension, and hypertensive patients with significantly elevated aldosterone/renin ratios. This lays the foundation for future precise antihypertensive strategies guided by aldosterone biomarkers.

 

 

·Primary aldosteronism (PA): As a monotherapy, it is expected to replace bridging management during long-term preoperative waiting periods;

·Chronic kidney disease (CKD) complicated with hypertension: joint research with SGLT2 inhibitor Farxiga is underway;

·Heart failure prevention: a preventive intervention study for patients with hypertension and subclinical heart failure.

AstraZeneca expects Baxbendy's peak sales in hypertension indications to reach $5 billion, and if successfully expanded to areas such as CKD and heart failure, the peak sales potential could reach $10 billion.

 

 

In February 2026, Baxdrostat officially applied for listing in China and is currently in the NMPA review stage. According to the practice of China's priority review and approval channel, the target time limit for priority review is about 130 working days (about 6 months).

The proportion of poorly controlled hypertension in China remains high. If estimated based on a 10% proportion of refractory hypertension, there are over 20 million potential beneficiaries in China. In addition, the proportion of aldosterone excess in diabetes and CKD patients in China is also high, and Baxfendy's dual benefits to this special group need to be further verified by local research.

Baxdrostat is not the only ASI currently under development. Lorundrostat from Mineralys Therapeutics is also in the FDA review phase (with a target review date of December 22, 2026). Baxdrostat has established a clear leading position in the ASI track with its longer half-life, better 24-hour coverage, and approved first mover advantage in the market.

 

The launch of Baxfengy is a landmark breakthrough in the field of hypertension drugs in the past 20 years. It not only fills the huge treatment gap of refractory and uncontrollable hypertension, but also opens up a new direction for precise treatment of hypertension with a new biological logic - inhibiting aldosterone overproduction from the root. This innovative therapy is expected to benefit millions of patients in China with poor blood pressure control in the near future, providing a new powerful weapon for the comprehensive prevention and control of cardiovascular diseases.