A Study to Assess Efficacy and Safety of Baxdrostat in Participants With Primary Aldosteronism

Inclusion Criteria:

• Male or female participants must be ≥ 18 years of age

• Participants with a documented diagnosis of PA that fulfils the criteria defined inthe 2016 or 2025 Endocrine Society Guidelines.

• Participants willing and able to cease dosing of MRA or potassium sparing diureticsper study requirement for participants taking an MRA or potassium sparing diureticat Screening.

• eGFR ≥ 45 mL/min/1.73m2 at Screening

• Serum potassium level ≥ 3.0 and < 5.0 mmol/L at Screening determined as per thecentral laboratory.

• Have a stable regimen of antihypertensive medications for at least 4 weeks prior torandomisation

• Mean seated SBP on AOBPM of ≥ 135 mmHg and ≤ 170 mmHg and mean DBP of

≤ 105 mmHg.

• Serum potassium (local lab) > 3.0 mmol/L at randomization.

Exclusion Criteria:

• If not taking an MRA or potassium sparing diuretic at Screening: Mean seated SBP > 170 mmHg or mean seated DBP >105 mmHg (on AOBPM).

If taking an MRA or potassium sparing diuretic at Screening: Mean seated SBP > 160 mmHg or mean seated DBP ≥ 100 mmHg.

• Previous surgical intervention for an adrenal adenoma or have a plannedadrenalectomy, renal nerve denervation, or adrenal ablative procedure during thecourse of the study.

• Has the following known secondary causes of HTN: renal artery stenosis, uncontrolledor untreated hyperthyroidism, uncontrolled or untreated hypothyroidism,pheochromocytoma, Cushing's syndrome, aortic coarctation.

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

• New York Heart Association functional HF class IV at Screening.

• Persistent atrial fibrillation.

• Treatment with any MRA or potassium-sparing diuretic within 2 weeks prior toRandomisation.