Heart tablet hailed as ‘Holy Grail’ after hypertension sufferers have been successfully cured of lethal situation in pivotal trial

A new blood pressure drug could provide a lasting cure for almost a million Britons in a breakthrough scientists are calling ‘extraordinary’ and ‘unexpected’.

Researchers in London have found that baxdrostat, hailed as a potential ‘Holy Grail’ treatment, could drive a common underlying cause of the condition into long-term remission.

In a small trial, the once-daily pill brought blood pressure down to normal levels by targeting an overactive hormone thought to be responsible for 800,000 cases in Britain. 

Remarkably, the improvements were still evident two years after patients stopped taking the pills.

Experts said the findings raise the prospect of something scientists have been trying to achieve for decades – curing a form of high blood pressure with a course of tablets rather than surgery.

The drug is not yet available on the NHS, but manufacturer AstraZeneca is seeking approval in the UK, where health watchdogs are assessing its ‘cost effectiveness’ for patients with uncontrolled or resistant high blood pressure.

It was approved by US health officials in May, although its potential to provide a lasting cure is still being investigated.

Around 16 million UK adults have high blood pressure, also known as hypertension, which dramatically increases the risk of heart attack, stroke, kidney disease and dementia.

However, in at least five per cent of cases – around 800,000 Britons – high blood pressure is caused by an underlying disorder known as primary aldosteronism.

This occurs when the adrenal glands produce too much aldosterone, a hormone that causes the kidneys to retain salt and water, driving up blood pressure.

For some patients, surgery to remove the affected adrenal gland can provide a cure. Others require lifelong medication to control the effects of the excess hormone.

Now researchers at Queen Mary University of London believe they may have found a way to tackle the problem at its source.

Their approach involves baxdrostat, a drug that blocks the production of aldosterone.

The idea was inspired by a 2005 study in mice, which found that suppressing the hormone caused the cells responsible for producing it to disappear.

Researchers wanted to establish whether the same effect could be achieved in humans, potentially offering a lasting cure without surgery.

A major trial last year had already shown that baxdrostat could lower blood pressure in patients who had failed to respond adequately to existing treatments.

In the latest study, 14 patients in the US took the drug once daily for six to 12 months.

Around two years after stopping treatment, researchers reassessed their blood pressure and hormone levels, comparing the results with measurements taken before they started taking the drug.

The most striking finding was that a key marker of excess aldosterone production had fallen by 99 per cent compared with before treatment.

This suggests the underlying hormonal disorder had gone into near-total remission, even though patients were no longer taking the drug.

Their blood pressure had also improved dramatically.

Average systolic blood pressure – the top number in a reading – fell from 142.4 to 117.2 millimetres of mercury (mmHg), a drop of around 25 points.

Under NHS guidance, a systolic reading of 140 mmHg or above is considered high, while a reading below 120 mmHg is generally regarded as healthy.

‘This follow-up study has generated some extraordinary and unexpected findings,’ said Mason Freeman, a professor at Harvard Medical School who led the first clinical study of baxdrostat.

He said the dramatic reduction in markers of excess aldosterone, alongside the improvement in blood pressure, ‘offers the very exciting possibility’ that patients could be cured with a once-daily pill.

Morris Brown, the study’s lead author and professor of endocrine hypertension at Queen Mary University of London, said: ‘While duly cautious about our findings because of the pragmatic nature of the study, they were predicted by previous experiments, and longer follow-up may justify a claim that a finite course of medication leads to infinite cure.

‘EASI-treatment is unlikely to be the elixir for most patients with hypertension. But the possibility of tablets achieving a surgical cure has long been a holy grail for this common type of hypertension.’

However, the findings are preliminary. With just 14 participants and no comparison group, the study cannot yet establish whether baxdrostat was responsible for the lasting improvements or whether patients have been permanently cured.

Researchers are now preparing a larger trial, called ELIXIR, to investigate whether the results can be replicated, with full findings expected in late 2028.

‘We are just awaiting the drug supply and the trial will begin hopefully any day,’ Prof Brown told the Daily Mail.

He said the first results could emerge within nine months of patients joining the trial.

However, he stressed that the study is separate from the regulatory approval process, which is based on much larger trials investigating the drug’s ability to lower blood pressure.

These have already led to its approval in the US, while UK health watchdog NICE is assessing whether it should be made available on the NHS to patients with uncontrolled or resistant hypertension.