Baxdrostat for High Blood Pressure

(Bax24 Trial)

No longer recruiting at 119 trial locations

Overseen By AstraZeneca Clinical Study Information Center

Age: 18+

Sex: Any

Trial Phase: Phase 3

Sponsor: AstraZeneca

Must be taking: Antihypertensives, Diuretics

Disqualifiers: Renal artery stenosis, Hyperthyroidism, Hypothyroidism, others

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 12 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new medication, Baxdrostat, to determine its effectiveness in lowering high blood pressure in individuals who have not responded to other treatments. The study compares Baxdrostat to a placebo (a pill with no active medicine) to evaluate its efficacy and safety. Individuals with high blood pressure who have taken at least three different blood pressure medications, including a diuretic, may qualify for this trial. As a Phase 3 trial, this study represents the final step before FDA approval, providing participants an opportunity to contribute to a potentially groundbreaking treatment.

Will I have to stop taking my current medications?

The trial requires participants to stay on their current medications, as they must have a stable regimen of at least three antihypertensive medications, including a diuretic, for at least four weeks before joining the study.

Is there any evidence suggesting that Baxdrostat is likely to be safe for humans?

Research has shown that baxdrostat is usually well-tolerated by people with hard-to-control high blood pressure. One study found that patients taking 2 mg of baxdrostat experienced an average drop of 15.7 mmHg in their top blood pressure number. Importantly, the study indicated that baxdrostat was generally well-tolerated, with most participants not experiencing serious side effects.

While some individuals might encounter mild side effects, data suggests that baxdrostat is safe for many with difficult-to-manage high blood pressure. Prospective trial participants can use this information to understand the safety of baxdrostat based on previous research. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for high blood pressure?

Baxdrostat is unique because it targets aldosterone synthase, an enzyme involved in producing aldosterone, a hormone that can increase blood pressure. Unlike standard treatments for high blood pressure, like ACE inhibitors or beta-blockers, which have broader mechanisms, Baxdrostat offers a more targeted approach. Researchers are excited about this treatment because it could provide a new option for patients who don't respond well to existing medications, potentially improving outcomes with fewer side effects.

What evidence suggests that Baxdrostat might be an effective treatment for high blood pressure?

In this trial, participants will receive either Baxdrostat or a placebo. Previous studies have shown that Baxdrostat significantly lowers systolic blood pressure in individuals with resistant hypertension, where blood pressure is difficult to control. Research indicates that Baxdrostat reduces blood pressure by about 9 to 10 mmHg, a meaningful decrease. Specifically, one study found that Baxdrostat lowered blood pressure by 15.7 mmHg from the starting point, even after accounting for placebo effects. This treatment targets aldosterone, a hormone that can increase blood pressure. Overall, these studies suggest that Baxdrostat could be effective for individuals whose blood pressure is not well-managed with other medications. ^{1 2 4 5 6}

Are You a Good Fit for This Trial?

This trial is for adults with resistant hypertension, meaning their blood pressure remains high despite taking at least three different blood pressure medications, including a diuretic. They must have specific levels of kidney function and potassium in their blood to join.

Inclusion Criteria

Serum potassium (K+) level ≥ 3.5 and < 5.0 mmol/L at Screening, determined as per central laboratory

My average walking blood pressure is 130 mmHg or higher.

Mean seated SBP on AOBPM of ≥ 140 mmHg and < 170 mmHg at Screening

Exclusion Criteria

Serum sodium level < 135 mmol/L at Screening, as per central laboratory

Mean seated DBP on AOBPM ≥ 110 mmHg at Screening

I have ongoing irregular heartbeats.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive 2 mg Baxdrostat or placebo orally once daily to assess the effect on ambulatory blood pressure

12 weeks

Regular visits for monitoring and assessment

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Baxdrostat

Trial Overview The study tests Baxdrostat's ability to lower systolic blood pressure compared to a placebo. Participants will be randomly assigned to receive either the drug or placebo once daily, and their 24-hour ambulatory blood pressure will be monitored.

How Is the Trial Designed?

Group I: 2 mg baxdrostat Experimental Treatment 1 Intervention

2 mg baxdrostat administered orally, once daily (QD).

Group II: Placebo Placebo Group 1 Intervention

Placebo administered orally, once daily (QD)

Who Is Running the Clinical Trial?

AstraZeneca

Lead Sponsor

Trials

4,491

Recruited

290,540,000+

Sir Pascal Soriot

AstraZeneca

Chief Executive Officer since 2012

Veterinary Medicine from École nationale vétérinaire d'Alfort, MBA from HEC Paris

Dr. Cristian Massacesi

AstraZeneca

Chief Medical Officer since 2021

MD from Marche Polytechnic University, Oncology training at Royal Marsden Hospital, Kaplan Comprehensive Cancer Center, and European Institute of Oncology

Pascal Soriot

AstraZeneca

Chief Executive Officer since 2012

Veterinary Medicine from École nationale vétérinaire d'Alfort, MBA from HEC Paris

Cristian Massacesi

AstraZeneca

Chief Medical Officer since 2021

MD from Marche Polytechnic University, Medical Oncology training at Royal Marsden Hospital, Kaplan Comprehensive Cancer Center, and European Institute of Oncology

Published Research Related to This Trial

Baxdrostat (CIN-107) is a selective aldosterone synthase inhibitor being tested as a treatment for drug-resistant hypertension, which is linked to serious cardiovascular issues.

While a phase 2 trial (BrigHTN) showed promising efficacy results, the HALO trial found no significant blood pressure-lowering effect of baxdrostat compared to placebo, indicating the need for further studies to assess its effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Baxdrostat: An Aldosterone Synthase Inhibitor for the Treatment of Systemic Hypertension. Dey, S., Frishman, WH., Aronow, WS.[2023]

Compound 7aa is a highly potent and selective inhibitor of CYP11B1, showing an IC50 of 9 nM, which is comparable to the existing drug osilodrostat, but with 1500-fold greater selectivity over CYP11B2.

In animal studies, compound 7aa effectively reduced plasma cortisol levels without affecting aldosterone production and showed no inhibition of other important enzymes, indicating a favorable safety profile for further development as a therapeutic option for diseases caused by excessive cortisol.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Design, Synthesis, and Biological Evaluations of Pyridyl 4,5,6,7-Tetrahydro-4,7-Methanobenzo[d]isoxazoles as Potent and Selective Inhibitors of 11&#946;-Hydroxylase. Yin, L., Pan, Y., Xue, Y., et al.[2022]

Aldosterone synthase inhibitors (ASI), particularly Baxdrostat, are a promising new class of medications that target resistant hypertension by reducing aldosterone production, which is crucial for blood pressure regulation.

Baxdrostat is currently in phase 3 trials and has shown efficacy in both animal and human studies, indicating its potential to effectively manage uncontrolled hypertension and related conditions like chronic kidney disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Baxdrostat: A Novel Aldosterone Synthase Inhibitor for Treatment Resistant Hypertension. Dogra, S., Shah, S., Gitzel, L., et al.[2023]

In a study involving 27 healthy volunteers, the co-administration of baxdrostat with metformin was found to be safe, with no serious adverse events or significant increases in side effects, indicating good tolerance of the combination.

Baxdrostat did not significantly alter the plasma levels or renal clearance of metformin, suggesting that diabetic patients with hypertension can take both medications without needing to adjust the metformin dose.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Results From a Randomized, Open-Label, Crossover Study Evaluating the Effect of the Aldosterone Synthase Inhibitor Baxdrostat on the Pharmacokinetics of Metformin in Healthy Human Subjects. Freeman, MW., Bond, M., Murphy, B., et al.[2023]

Baxdrostat, a selective aldosterone synthase inhibitor, was found to be safe and well-tolerated in a study of 54 healthy volunteers, with no serious adverse events reported and only mild side effects observed.

The study demonstrated that baxdrostat effectively reduced plasma aldosterone levels by 51 to 73% after 10 days of treatment at doses of 1.5 mg or higher, while having no significant impact on cortisol levels, indicating its selective action.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Results from a phase 1, randomized, double-blind, multiple ascending dose study characterizing the pharmacokinetics and demonstrating the safety and selectivity of the aldosterone synthase inhibitor baxdrostat in healthy volunteers. Freeman, MW., Bond, M., Murphy, B., et al.[2023]

Baxdrostat, an aldosterone synthase inhibitor, shows promise in effectively managing systemic hypertension (HTN) by potentially overcoming the limitations of traditional treatments that often fail to control blood pressure adequately.

The mechanism of baxdrostat may enhance sodium and blood pressure regulation while reducing oxidative stress and improving endothelial function, which could lead to better cardiovascular outcomes for patients with resistant HTN.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Aldosterone Synthase Inhibitors and Dietary Interventions: A Combined Novel Approach for Prevention and Treatment of Cardiovascular Disease. Awosika, A., Khan, A., Adabanya, U., et al.[2023]

Citations

1. astrazeneca.com astrazeneca.com/content/astraz/media-centre/press-releases/2025/baxdrostat-met-the-primary-endpoint-in-bax24-phase-iii-trial-in-patients-with-resistant-hypertension.html

Baxdrostat met the primary endpoint in Bax24 Phase III trial ... Baxdrostat demonstrated a statistically significant and highly clinically meaningful reduction in 24-hour ambulatory systolic blood pressure ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7618089/

Baxdrostat Efficacy and Safety in Uncontrolled and Resistant ... Baxdrostat added to background therapy resulted in a reduction in seated-SBP at 12 weeks compared with placebo in patients with uncontrolled or ...

3. astrazeneca-us.com astrazeneca-us.com/media/press-releases/2025/Baxdrostat-demonstrated-statistically-significant-and-clinically-meaningful-reduction-in-systolic-blood-pressure-in-patients-with-hard-to-control-hypertension-in-the-BaxHTN-Phase-III-trial.html

Baxdrostat demonstrated statistically significant and ... Baxdrostat 2mg lowered systolic blood pressure by 15.7 mmHg (9.8 mmHg placebo-adjusted) from baseline, and was generally well tolerated with ...

4. nature.com nature.com/articles/s41440-025-02415-5

Baxdrostat and the future of aldosterone-targeted therapy Published in The New England Journal of Medicine [2], the study showed that once-daily baxdrostat reduced systolic blood pressure by about 9–10 ...

5. nejm.org nejm.org/doi/abs/10.1056/NEJMoa2507109

Efficacy and Safety of Baxdrostat in Uncontrolled and ... In several studies, baxdrostat, an aldosterone synthase inhibitor, reduced the seated systolic blood pressure of patients with uncontrolled or ...

6. clinicaltrials.gov clinicaltrials.gov/study/NCT05966324?term=AREA%5BInterventionSearch%5D(ALDOS)%20AND%20AREA%5BStudyType%5D(INTERVENTIONAL)&rank=2

Study Details | NCT05966324 | Baxdrostat Safety, ... Main Objectives were: To assess the safety and tolerability of single and multiple oral doses of baxdrostat in healthy Japanese subjects.