AstraZeneca Baxdrostat Shows Breakthrough 14 mmHg 24-Hour Blood Pressure Reduction in Resistant Hypertension: Bax24 Phase III Trial Results

AstraZeneca announced compelling results from the Bax24 Phase III clinical trial of Baxdrostat, an investigational aldosterone synthase inhibitor designed for patients with resistant hypertension. The trial demonstrated a statistically significant and highly clinically meaningful placebo-adjusted reduction of 14.0 mmHg in 24-hour ambulatory systolic blood pressure (SBP), marking a potentially transformative advance in the management of difficult-to-treat hypertension.

Study Design and Patient Population

The Bax24 trial was a randomized, double-blind, placebo-controlled study conducted globally across 79 countries. It enrolled patients with resistant hypertension defined as blood pressure that remains high despite the use of multiple antihypertensive medications. The trial specifically evaluated the effect of once-daily 2 mg Baxdrostat on 24-hour ambulatory SBP, a measure recognized as a stronger predictor of cardiovascular outcomes than office blood pressure readings

Key Efficacy Results

Baxdrostat achieved its primary endpoint by significantly reducing 24-hour ambulatory systolic blood pressure by 14.0 mmHg compared with placebo. This blood pressure lowering effect was sustained throughout the entire 24-hour dosing interval, including during nighttime and early morning periods when cardiovascular risk is at its peak. Secondary endpoints also showed substantial and statistically significant reductions in ambulatory nighttime average SBP (approximately 13.9 mmHg reduction) and seated SBP (about 10.3 mmHg reductions).

More than 70% of patients treated with Baxdrostat achieved guideline-recommended blood pressure targets consistently over 24 hours. These findings highlight Baxdrostat’s potential to offer continuous and consistent blood pressure control for patients whose hypertension has been hard to manage by current standards.

About Baxdrostat

Baxdrostat is a highly selective inhibitor of aldosterone synthase, the enzyme responsible for producing aldosterone a hormone that raises blood pressure and contributes to cardiovascular and kidney disease. By blocking aldosterone synthesis, Baxdrostat addresses a key pathogenic driver of resistant hypertension. 

The long half-life of Baxdrostat (26 to 30 hours) supports its ability to maintain stable plasma levels and consistent blood pressure control around the clock, including overnight a critical period when many cardiovascular events occur.

Safety and Tolerability

The Bax24 trial reported no unexpected safety findings or treatment-related serious adverse events, marking Baxdrostat as well-tolerated in this patient population. The safety profile complements the robust efficacy data and supports further development and potential regulatory approval.

Key Opinion

Dr. Bryan Williams, the trial’s principal investigator and chair of medicine at University College London, described the results as “remarkable” and a potential shift in treatment paradigms for resistant hypertension. Dr. Mohit Gupta, a leading cardiologist, called the data “exciting and promising,” emphasizing the possibility of better managing a large group of patients who currently have limited options.

AstraZeneca’s Executive VP of Biopharmaceuticals R&D, Sharon Barr, highlighted Baxdrostat potential to reduce cardiovascular events through improved 24-hour blood pressure control. Following these promising results, Baxdrostat may redefine treatment possibilities for millions of patients globally who struggle with resistant hypertension despite current therapies.

AstraZeneca’s Baxdrostat Clinical Development Program

AstraZeneca’s Baxdrostat has shown consistent promise in treating resistant hypertension across multiple rigorous trials. In addition to the recent impressive results from the Bax24 Phase III trial demonstrating a 14.0 mmHg placebo-adjusted reduction in 24-hour ambulatory systolic blood pressure, earlier data from the BaxHTN trial (ClinicalTrials.gov ID: NCT06034743) also highlighted significant efficacy and safety in patients with uncontrolled and resistant hypertension. Together, these studies reinforce the potential of Baxdrostat as a groundbreaking treatment option for patients with difficult-to-control blood pressure.