For people with chronic kidney disease, high blood pressure can become a frustrating loop. The kidneys help manage fluid and salt, but when they weaken, blood pressure can rise, and that extra pressure can damage the kidneys even more.
A new study suggests baxdrostat, a pill that blocks production of aldosterone, may help break part of that loop.
In a phase 2 trial, the drug lowered systolic blood pressure more than placebo and cut a urine marker tied to kidney and heart risk, though researchers still need longer trials to prove it prevents kidney failure.
The hormone at the center
Aldosterone is made by the adrenal glands, small glands that sit above the kidneys. Its job is simple enough: help the body hold the right balance of salt and water.
Too much aldosterone, however, can push the body to retain sodium and fluid. That can raise blood pressure, like turning up pressure in a garden hose, and over time it may contribute to stiff blood vessels and kidney scarring.
Baxdrostat belongs to a class known as aldosterone synthase inhibitors. In plain language, it is designed to reduce aldosterone at the source instead of only trying to deal with its effects later.
Who was studied
The trial focused on 195 adults with chronic kidney disease and uncontrolled hypertension. Many already had a serious kidney risk profile, and most were taking standard blood pressure drugs that act on the same broad hormone network.
At the start, their average top blood pressure number was about 151 mm Hg. That is the number doctors watch closely because it reflects the pressure in arteries when the heart squeezes, not during the brief rest between beats.
The study’s lead author, Dr. Jamie P. Dwyer of University of Utah Health, described the conditions as a dangerous cycle. He said, “High blood pressure can worsen kidney function and declining kidney function can further elevate blood pressure.”
What the pill changed
After 26 weeks, patients taking baxdrostat had an average systolic blood pressure drop 8.1 mm Hg greater than those on placebo. That may sound small on paper, but in medicine, sustained changes in blood pressure can matter a great deal.
The more eye-catching finding came from urine tests. Albumin, a blood protein that should mostly stay out of urine, was 55% lower in the baxdrostat group compared with placebo in an exploratory analysis.
Why does that matter? When albumin leaks into urine, it can be a sign that the kidney’s filtering system is under strain. It is also linked with higher cardiovascular risk, so the finding hints at possible kidney and heart benefits beyond the blood pressure number itself.
Safety and the catch
The study did not report deaths or unexpected safety problems. But it did show one clear warning sign: high potassium in the blood appeared in 41% of people receiving baxdrostat, compared with 5% in the placebo group.
High potassium matters because it can affect heart rhythm, especially in people whose kidneys already struggle to balance minerals in the bloodstream. Most cases in the trial were mild to moderate, but it is not a detail doctors can brush aside.
Dr. Jordana B. Cohen, who was not involved in the study, said the results were encouraging because people with kidney disease have often been left out of drug trials.
She serves in the American Heart Association’s hypertension and kidney science work and is with the Perelman School of Medicine at the University of Pennsylvania.
Why approval is only part of the story
There is an important timing wrinkle here. When the kidney-focused phase 2 results were presented in 2025, baxdrostat had not yet been approved by the U.S. Food and Drug Administration.
The drug has since been approved in the United States as Baxfendy, used with other blood pressure medicines for adults whose hypertension remains inadequately controlled. The current prescribing information points to blood pressure treatment, not proven kidney protection.
At the end of the day, the kidney signal is promising, not settled. A better blood pressure reading is important, but proving fewer cases of kidney failure, heart failure, stroke, or cardiovascular death takes larger and longer studies.
The next test
Later phase 3 data have strengthened the blood pressure story. In BaxHTN, a large trial in uncontrolled or resistant hypertension, baxdrostat once daily produced significant systolic blood pressure reductions against placebo at 12 weeks, with no unanticipated safety findings.
For kidney disease, the big question is still open. AstraZeneca is running a phase 3 renal outcomes study of baxdrostat with dapagliflozin in people with chronic kidney disease and high blood pressure, with an estimated enrollment of 5,000 and a completion date listed for 2029.
So what should patients take from this? Baxdrostat may represent a new way to treat stubborn high blood pressure, and possibly a new route to protect the kidneys, but the strongest proof is still ahead. That is the part worth watching.
The main study has been published in the Journal of the American Society of Nephrology.
