Breakthrough pill could help millions with resistant high blood pressure

High blood pressure affects more than 1.3 billion people around the world. It’s one of the most common conditions linked to heart disease, stroke, kidney failure, and early death. For many people, medication helps. But for about half of all patients, blood pressure stays too high—even with multiple drugs.

This condition is known as resistant or uncontrolled hypertension. In the UK alone, around 14 million people have high blood pressure. Globally, more than half of those affected now live in Asia. Countries like China and India account for over 400 million cases combined. This trend has shifted from wealthier Western countries due to diet changes, including less salt intake in some regions.

Until now, managing this stubborn condition has been difficult. Most treatments only offer limited results and may cause serious side effects. But a new drug, tested in a large international clinical trial, may finally offer real hope.

A major Phase III clinical trial known as BaxHTN tested a drug called baxdrostat. This trial was led by Professor Bryan Williams from University College London (UCL) and sponsored by AstraZeneca. The findings were shared at the 2025 European Society of Cardiology Congress and published in the New England Journal of Medicine.

The trial included nearly 800 people across 214 clinics worldwide. All participants had either uncontrolled or resistant hypertension. They were already taking at least two or three medications, including a diuretic, but their systolic blood pressure remained between 135 and 170 mmHg.

Researchers randomly assigned patients to take either a placebo or baxdrostat in pill form once a day. One group took a 1 mg dose, and another took 2 mg. After 12 weeks, the results were clear: baxdrostat lowered blood pressure significantly more than the placebo.

On average, those taking 1 mg saw a drop of 14.5 mmHg. The 2 mg group experienced a 15.7 mmHg reduction. In comparison, the placebo group only dropped by 5.8 mmHg. That’s a difference of about 9–10 mmHg—enough to reduce the risk of heart attack and stroke in a meaningful way.

Even more striking, about 4 out of 10 people in the baxdrostat groups reached healthy blood pressure targets. Fewer than 2 in 10 people in the placebo group achieved the same.

“This level of reduction is linked to substantially lower risk of heart attack, stroke, heart failure and kidney disease,” said Professor Williams. “It’s exciting to see such results in patients where existing treatments haven’t worked.”

So what makes baxdrostat different?

The drug targets a key hormone called aldosterone. This hormone plays a major role in regulating how the kidneys manage salt and water. For some people, their bodies make too much aldosterone, causing them to retain salt and water. This leads to higher blood pressure and makes treatment very difficult.

This condition, known as aldosterone dysregulation, has challenged scientists for decades. Traditional drugs like mineralocorticoid receptor antagonists (MRAs) have tried to block the effects of aldosterone. But MRAs often come with serious side effects and can cause the body to fight back by raising aldosterone levels even more.

Baxdrostat offers a smarter solution. It blocks aldosterone at the source—by stopping the enzyme that creates it. This type of medication is called an aldosterone synthase inhibitor. Baxdrostat is also highly selective and has a long half-life, meaning it works all day with just one pill.

“This suggests that aldosterone is playing an important role in causing difficult to control blood pressure in millions of patients,” said Professor Williams. “It offers hope for more effective treatment in the future.”

The trial also looked at side effects. The main concern with drugs like this is potassium levels. Too much potassium in the blood, a condition called hyperkalemia, can be dangerous. In the trial, high potassium levels (over 6.0 mmol/L) were rare. They occurred in 2.3% of patients taking 1 mg, 3.0% of those on 2 mg, and only 0.4% in the placebo group.

No unexpected safety issues were found, and most people tolerated the drug well throughout the 12 weeks. Many continued to benefit from lower blood pressure even at 32 weeks, showing the drug’s lasting impact.

This research may change how doctors treat high blood pressure. Until now, many patients have cycled through drug after drug with little success. The BaxHTN study suggests that one of the biggest reasons for this failure—aldosterone excess—can now be directly addressed.

The current target for blood pressure, based on 2024 guidelines, is less than 130/80 mmHg. That’s lower than the previous target of 140/90 mmHg. As a result, even more people now qualify as having uncontrolled hypertension.

“Half of people treated for hypertension do not have it under control,” said Professor Williams. “That’s a conservative estimate. With newer targets, the actual number is likely much higher.”

With baxdrostat, the chance of reaching those stricter targets improves dramatically. The drug could help up to 500 million people worldwide—nearly 10 million in the UK alone.

Baxdrostat isn’t yet available on the market. But the BaxHTN trial brings it one step closer to approval. Future studies may explore how it works in different populations or alongside other treatments. Researchers may also track long-term benefits and risks over several years.

Past trials gave mixed results. A 12-week Phase II study, BrigHTN, showed promising outcomes. However, the HALO trial did not find significant improvements. A smaller study in patients with primary aldosteronism showed strong blood pressure reductions. Now, with data from nearly 800 patients and longer-term follow-up, the evidence is stronger than ever.

It took years of research, setbacks, and careful testing to get here. But with baxdrostat, the future looks brighter for millions living with hard-to-treat hypertension.

Note: The article above provided above by The Brighter Side of News.

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