This is a Phase III, multicentre, randomised, double-blinded, placebo-controlled, parallel group study to evaluate the safety, tolerability and effect of 1 or 2 mg baxdrostat versus placebo, administered QD orally, on the reduction of SBP in approximately 300 participants aged ≥ 18 years with HTN (≥ 140 mmHg at Screening; ≥ 135 mmHg at randomisation) despite a stable regimen of 2 antihypertensive agents at baseline, one of which is a diuretic (uHTN); or ≥ 3 antihypertensive agents at baseline, one of which is a diuretic (rHTN).