FDA approves baxdrostat, the first aldosterone synthase inhibitor for hard-to-control hypertension

AstraZeneca's once-daily pill, cleared as add-on therapy, lowered systolic pressure by about 9 to 10 mmHg over placebo in the Phase 3 BaxHTN trial.

In mid-May 2026 the FDA approved baxdrostat (Baxdro), AstraZeneca’s first-in-class oral aldosterone synthase inhibitor, as add-on therapy for adults whose blood pressure stays high despite other medications. It is the first drug in its class to reach the U.S. market, cleared at once-daily doses of 1 mg or 2 mg.

The approval targets a stubborn clinical problem: patients whose hypertension persists on two, three, or more agents. Aldosterone dysregulation is a recognized driver of that resistance, and baxdrostat works by inhibiting the enzyme that synthesizes the hormone rather than by blocking its receptor.

What the pivotal trial showed

The decision rests on BaxHTN (NCT06034743), a Phase 3, multinational, double-blind, randomized, placebo-controlled trial. After a two-week placebo run-in, 796 patients were randomized 1:1:1 to baxdrostat 1 mg, baxdrostat 2 mg, or placebo on top of background therapy; 794 were treated (264, 266, and 264, respectively). Enrollees had seated systolic pressure of 140 to under 170 mmHg despite stable treatment with two antihypertensives (uncontrolled hypertension) or three or more (resistant hypertension), one of which was a diuretic.

The primary endpoint was the change in seated systolic blood pressure from baseline to week 12. Least-squares mean reductions were 14.5 mmHg (95% CI, -16.5 to -12.5) with 1 mg, 15.7 mmHg (95% CI, -17.6 to -13.7) with 2 mg, and 5.8 mmHg (95% CI, -7.9 to -3.8) with placebo.

The placebo-corrected difference was 8.7 mmHg (95% CI, -11.5 to -5.8) for the 1-mg dose and 9.8 mmHg (95% CI, -12.6 to -7.0) for the 2-mg dose (P<0.001 for both).

On safety, a potassium level above 6.0 mmol/L — a known concern with drugs acting on the aldosterone axis — was reported in 6 patients (2.3%) on 1 mg, 8 patients (3.0%) on 2 mg, and 1 patient (0.4%) on placebo. Importantly, BaxHTN excluded the patients at highest risk of this harm: eligibility required an eGFR of at least 45 mL/min/1.73m2 and a baseline serum potassium below 5.0 mmol/L, so people with significant chronic kidney disease or pre-existing hyperkalemia were not studied. Because aldosterone-axis drugs raise potassium most in patients with reduced kidney function, the observed 2-3% rate of potassium above 6.0 mmol/L may understate hyperkalemia risk in the broader real-world population, where chronic kidney disease is common. Potassium and kidney function require monitoring with this drug class, meaning hyperkalemia is a managed, not negligible, risk rather than an isolated statistic.

BaxHTN measured blood pressure, a surrogate, over 12 weeks; it was not designed to show reductions in heart attacks, strokes, or death, and longer-term cardiovascular and renal outcomes remain to be established. The trial was funded by AstraZeneca and others. The full results were published in the New England Journal of Medicine.

Trials Today

Phase 3 VECTRA-01 (AZD2265 / 225Ac-PSMA-I&T, mCRPC) — Recruiting; alpha-emitter PSMA radioligand vs SOC after prior beta-emitter, taxane and ARPI; ~670 patients; dual primary rPFS and OS.

Phase 3 PRECISE-HD (pridopidine, Huntington's disease) — Newly registered; 400 patients not on antidopaminergics; primary is 52-week change in composite cUHDRS.

Phase 3 QUILT-2.023 (nogapendekin alfa inbakicept, 1L NSCLC) — Terminated; sponsor registry note states no active subjects, no efficacy results posted (enrolled 102).

Phase 3 Atezolizumab + standard HER2 therapy, 1L HER2+ mBC (NRG/NCI) — Terminated for poor accrual (190 enrolled); posted PFS 52.3% vs 40.5% is a numerical, underpowered signal only (CIs overlap, no HR).

Phase 2/3 Peri-operative nivolumab + ipilimumab, esophageal/GEJ adenocarcinoma (NCI) — Suspended after enrolling 278; registry summary gives no reason, so cause is unconfirmed. Watch item.

At the Agencies

Baxdrostat (Baxfendy), AstraZeneca — FDA approval May 18, 2026; first-in-class aldosterone synthase inhibitor for uncontrolled/resistant hypertension; BaxHTN placebo-adjusted SBP -9.8 mmHg.

Bulevirtide (Hepcludex), Gilead — FDA accelerated approval May 22, 2026; first US therapy for chronic hepatitis delta; surrogate week-48 combined response 48% vs 2%, confirmatory data required.

Pivekimab sunirine (Decnupaz), AbbVie — FDA approval May 27, 2026; first CD123-directed ADC for ultra-rare BPDCN; single-arm CADENZA CR/CRc 69.7% in treatment-naive (n=33).

Nerandomilast (Jascayd), Boehringer Ingelheim — EMA CHMP — Positive CHMP opinion (18-21 May 2026) for IPF and PPF; oral PDE4B inhibitor; FIBRONEER-IPF met primary FVC endpoint, key secondary not met. EC decision pending.