New research shows that baxdrostat, a medication for high blood pressure, kept blood pressure lower for up to two years after patients stopped taking it, with some no longer requiring any hypertension medication.
Study findings
Patients who took baxdrostat daily for six to 12 months experienced improvements in blood pressure during the course. In follow-up research, the positive effects persisted for up to two years afterwards, with some patients potentially cured of the condition entirely.
Prof Morris Brown, a hypertension specialist at Queen Mary University of London, who led the study, said: “It’s very exciting to see. Just under a quarter of the patients came off all treatment and had completely normal blood pressure.”
How baxdrostat works
High blood pressure affects around one in three adults in the UK, about 16 million people, yet millions remain undiagnosed because the condition rarely causes noticeable symptoms. Baxdrostat works by blocking the production of a hormone called aldosterone, which helps the kidneys regulate salt and water. Some people produce too much aldosterone, which increases their blood pressure. Blocking this hormone directly addresses the “core problem” behind high blood pressure.
Previous drugs have blocked aldosterone receptors, but these had undesirable side effects and did not act on the hormone directly. Patients with hypertension that cannot be controlled by existing medications may benefit from the treatment. The National Institute for Health and Care Excellence (Nice) is currently evaluating it, with the drug potentially becoming available through the NHS next year.
Clinical trial results
In a previous test, baxdrostat was trialled in 796 patients at 214 clinics worldwide and caused blood pressure to drop by 9-10mmHg more than those taking a placebo in three months. About four in 10 patients taking the new class of drug reached a healthy blood pressure level compared with fewer than two in 10 taking a placebo.
Trial lead Prof Bryan Williams, of UCL, said at the European Society for Cardiology’s annual conference last year: “I’ve never seen blood pressure reductions of this magnitude with a drug. High blood pressure is hard to control. Despite many treatments and a lot of discussion it’s still the single most important preventable cause of premature death globally. This drug development is really a triumph of scientific discovery.”
Prof Williams added: “This is a potential game-changer for patients because, despite the best efforts of clinicians and the drugs they have available, at least 50% of patients even in the most developed healthcare systems don’t have their blood pressure controlled. We saw almost a 10mmHg reduction in blood pressure, from a baseline of 149. That is a big drop in blood pressure. That would reduce [the chance of a] stroke by about 40% and heart disease by about 25%.”
Long-term effects and next steps
The possibly curative properties of baxdrostat emerged in a small study tracking 14 patients whose hypertension improved significantly during a three-month trial of the medication. They continued with the daily tablets for six to 12 months before stopping. When doctors examined the patients up to two years afterwards, their blood pressure remained lower. The findings are published in the New England Journal of Medicine.
Mason Freeman, a professor of medicine at Harvard University, who took part in the research, said it was premature to determine whether some patients had been cured, with a larger trial now under way to establish this. “If this effect is common and very persistent then the approach to diagnosing and treating these patients is likely to dramatically change,” he said. “Everyone could be treated with the ASI in initial suspicion of the condition and if they responded well they could avoid the invasive diagnostic procedures and the surgery.”
Prof Brown believed the drug might cure primary aldosteronism based on an experiment in mice conducted 20 years ago. It demonstrated that removing the gene required to produce aldosterone resulted in the loss of cells that generated the hormone. He believes baxdrostat produces a similar effect. When the drug suppresses aldosterone it triggers a surge in highly active molecules known as reactive oxygen species. These may specifically target and destroy the cells responsible for overproducing the hormone.
Prof Brown said: “Those oxygen radicals are killing the cells and they disappear. That’s what I think the mechanism is and it’s testable, it’s something we’re doing now in the laboratory.”
