What Is It, and Why Does It Matter?
Baxfendy (baxdrostat), the first in a new drug class known as aldosterone synthase inhibitors (ASIs), is now approved for adults who still have high blood pressure despite taking other antihypertensive medications. It reduces blood pressure by stopping the body from making aldosterone, a hormone that causes your kidneys to retain salt and water. Aldosterone has a key role in difficult-to-manage high blood pressure, so preventing its production could help when standard therapies haven't been effective enough.
High blood pressure, or hypertension, impacts roughly 1.4 billion people around the world. About half of people in the United States who already take multiple medicines continue to have trouble controlling their blood pressure. This is a major concern because poorly managed high blood pressure is a top risk factor for heart disease, stroke, kidney problems, and premature death. Reducing blood pressure helps lower the chances of these serious complications, particularly strokes and heart attacks.
Baxfendy's novel mechanism may provide an alternative for those whose blood pressure stays high despite other treatments.
Why Was It Approved?
This approval is based on a placebo-controlled study in adults whose high blood pressure remained uncontrolled even while they were taking at least two blood pressure medicines, including a diuretic (water pill). People in the study received either Baxfendy 2 mg, Baxfendy 1 mg, or a placebo once daily for 12 weeks, along with their existing blood pressure medicines.
After 12 weeks, Baxfendy performed significantly better than the placebo in reducing blood pressure. Those taking the 2 mg dose had a systolic blood pressure (top number) reduction of approximately 16 mm Hg, which was about 10 mm Hg greater than the placebo's reduction. Those on the 1 mg dose saw their systolic blood pressure decrease by roughly 15 mm Hg, which was approximately 9 mm Hg greater than the placebo's reduction.
The most frequently reported side effect was high potassium levels, occurring in roughly 10% of people taking the 2 mg dose and about 7% on the 1 mg dose, versus about 3% with the placebo. Other side effects were less common but included low blood pressure, reduced sodium levels, dizziness, and muscle spasms.
What Do I Need to Know?
Baxfendy comes as a tablet that is taken by mouth once daily. It may be taken with or without food but should be swallowed whole without cutting, crushing, or chewing. If you forget a dose, simply take your next scheduled dose at the regular time. Do not take two doses on the same day.
Your health care provider will monitor your potassium and sodium levels before you begin treatment and regularly while you're taking this medicine. More frequent testing may be necessary if you're over 65 years old, have diabetes or kidney disease, or take other medicines that can change potassium levels. While on Baxfendy, speak with your health care provider before using potassium supplements or salt substitutes containing potassium.
The safety of taking Baxfendy during pregnancy is unclear, and you should let your health care provider know if you're pregnant, planning pregnancy, or breastfeeding. Continue taking your other blood pressure medicines as directed unless your health care provider advises otherwise. Ensure that they are also aware of all other medicines you take, including prescription and over-the-counter drugs, vitamins, and herbal supplements, to avoid possible interactions.