AZ uses a priority review voucher for baxdrostat filing

AstraZeneca is leaving no stone unturned in its effort to make baxdrostat the first aldosterone synthase inhibitor (ASI) to get approval for hard-to-treat hypertension.

The FDA has now started a review of the highly anticipated drug, and AZ is using a priority review voucher to shorten the timeline for a potential approval to the second quarter of 2026, which should extend the lead over its main rival among ASI developers, Mineralys.

AZ has previously said that, given the massive unmet need among patients with high blood pressure that does not respond to current antihypertensive medicines, baxdrostat could become a $5 billion-a-year product.

There are around 1.4 billion people worldwide living with hypertension, and in the US approximately half of patients on multiple drugs to control their blood pressure do not meet their treatment targets.

That massive potential explains AZ's urgency as it tries to keep ahead of Mineralys and its lorundrostat ASI candidate, which has also cleared late-stage clinical development and is heading for an FDA filing around the end of this year or early in 2026.

AZ's filing is based on the results of the BaxHTN trial, which looked at the use of baxdrostat as an add-on therapy for uncontrolled or treatment-resistant hypertension and showed statistically significant reductions in blood pressure compared with placebo at 12 weeks.

Patients receiving a 2 mg daily dose of baxdrostat saw an average 15.7 mmHg drop from baseline in seated systolic blood pressure (SBP) at that timepoint, equivalent to a placebo-adjusted decline of 9.8 mmHg. For the 1 mg dose group, the two values were 14.5 mmHg and 8.7 mmHg, respectively.

While there are always issues with comparing separate clinical trials of two different medicines, the results of BaxHTN look comparable to those with Mineralys' drug in the Advance-HTN study, suggesting that being the first mover and commercial muscle may determine which of the two ASIs takes the lead in the market.

"This priority review demonstrates our commitment to advancing baxdrostat as a potential first- and best-in-class aldosterone synthase inhibitor for the millions of people living with hard-to-control hypertension as quickly as possible," said Sharon Barr, AZ's head of biopharmaceuticals R&D.

"The substantial reduction in systolic blood pressure seen in the BaxHTN trial underscores baxdrostat's novel mechanism of action and its potential to bring innovation to a disease area that has seen limited progress in over two decades," she added.

Last year, Idorsia Pharma claimed FDA approval for Tryvio (aprocitentan) as the first endothelin receptor antagonist for resistant hypertension, adding to the well-established treatment options for patients based on diuretics, calcium channel blockers, and renin-angiotensin system-targeting drugs.

AZ, meanwhile, is also developing baxdrostat chronic kidney disease (CKD) and prevention of heart failure as a combination therapy with its blockbuster SGLT2 inhibitor Farxiga/Forxiga (dapagliflozin). Mineralys is taking a similar approach, looking at extending the use of lorundrostat into CKD, as well as obstructive sleep apnoea (OSA) with hypertension.

AZ acquired baxdrostat when it bought CinCor Pharma for $1.3 billion in 2023.

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