While sparsentan blocks both ETA and AT1 receptors, atrasentan (Vanrafia) is a targeted therapy that focuses only on ETA receptors. In 2025, it received FDA approval to treat IgAN.
How Atrasentan Works
By blocking ETA receptors, atrasentan helps decrease stress on the kidneys, which can reduce inflammation and lower proteinuria without suppressing your immune system, says Garimella.
In a study, adults taking atrasentan had a 38 percent reduction in proteinuria after 36 weeks, compared with a 3 percent reduction in those taking a placebo (a pill containing no medication).
All study participants continued standard supportive care, such as ACE inhibitors or ARBs, and some also took SGLT2 inhibitors.
Atrasentan is a pill taken once a day by mouth. Although it helps lower proteinuria, researchers are still determining whether it also slows long‑term loss of kidney function.
Who Is Eligible for Atrasentan?
To be eligible for atrasentan, you must be an adult with primary IgAN at risk for faster disease progression.
This typically means having proteinuria, measured as a urine protein-to-creatinine ratio (uPCR) of 1.5 grams per gram or higher, despite receiving supportive care.
UPCR is a spot test that measures protein leakage in the urine. Your nephrologist will consider your proteinuria, kidney function, and overall health to see if this treatment is appropriate for you.
Atrasentan can be added to ACE inhibitors and ARBs, whether or not you’re also taking an SGLT2 inhibitor, says Garimella. It’s also an option if you want to avoid immunosuppressive medications like steroids, or if you’ve had liver‑related side effects with sparsentan, he says.
Some medications can interfere with how atrasentan works. These include certain antibiotics and seizure medications. Others, like the antifungal drug ketoconazole, can cause higher amounts of the medication to build up in your body.
Let your nephrologist know about all medications and supplements you take.
Atrasentan can cause serious harm to a developing baby, so it’s not recommended if you’re pregnant or planning to become pregnant.
People who can become pregnant should use effective birth control while taking this medication and for two weeks after stopping treatment.
Common Side Effects
Common atrasentan side effects include the following:
- Swelling in the legs, ankles, or feet
- Anemia
- Fluid retention
- Elevated liver enzymes
