A short course of pills may offer a lasting cure for one of the most common hormonal causes of high blood pressure, according to a small study published in the New England Journal of Medicine.
Fourteen patients with primary aldosteronism, treated at eight centres across the United States, took the drug baxdrostat daily for six to twelve months and then stopped. Up to two years later, the main marker of excess aldosterone production in their blood remained 99 per cent lower than before treatment, and their average blood pressure was 25 points lower. Just under a quarter of the patients came off all blood pressure medication and had completely normal readings. One patient has now been off the drug for three years.
Primary aldosteronism is a condition in which benign nodules on the adrenal glands produce too much aldosterone, a hormone that makes the kidneys retain salt and drives blood pressure up. It is thought to cause between 5 and 10 per cent of all cases of high blood pressure, and as many as a million people in Britain may have it. Until now, the only cure has been surgery to remove the affected adrenal gland.
Baxdrostat belongs to a newer class of drugs known as aldosterone synthase inhibitors, which block the CYP11B2 enzyme the body uses to make aldosterone. The researchers predicted that a prolonged course might do more than suppress the hormone temporarily: an experiment in mice in 2005 showed that deleting the gene for aldosterone synthase caused the hormone-producing cells to disappear, suggesting the drug could clear the overactive cell clusters in the adrenal gland altogether.
The researchers themselves urge caution. The study followed only 14 patients, the follow-up was pragmatic rather than a controlled trial, and it is too early to say any of them is cured. “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,” said Professor Morris Brown, the study’s lead author and professor of endocrine hypertension at Queen Mary University of London. His co-author, Professor Mason Freeman of Harvard Medical School, said a larger trial now under way would be needed to find out whether patients can truly be cured.
That larger prospective trial, called ELIXIR, is already recruiting. Baxdrostat was approved in the United States earlier this year for patients whose blood pressure remains dangerously high despite existing drugs, and it is being assessed by the National Institute for Health and Care Excellence, which could make it available through the NHS next year. The researchers stressed the treatment is unlikely to help most people with high blood pressure — only the minority whose condition is driven by excess aldosterone.
Sources: New England Journal of Medicine, “Hyperaldosteronism Remission after Extended Aldosterone Synthase Inhibition” (https://www.nejm.org/doi/10.1056/NEJMc2611265); News-Medical, “New treatment may offer lasting cure for hormone-related hypertension” (https://www.news-medical.net/news/20261108/New-treatment-may-offer-lasting-cure-for-hormone-related-hypertension.aspx); Queen Mary University of London via EurekAlert.
