Kidney disease drug may reduce urine protein levels in IgAN patients
One-year study of finerenone also shows stable kidney function
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A doctor consults with a patient seated on an examination table. (Photo by iStock)
Finerenone, an oral medication approved for diabetes-related chronic kidney disease, may reduce urine protein levels and stabilize kidney function in adults with immunoglobulin A nephropathy (IgAN).
That’s according to a one-year real-world study in China, which also showed benefits among participants who were not receiving immunosuppressive therapy, as well as a favorable safety profile for finerenone.
“These findings support finerenone as an important component of supportive care in IgAN, regardless of whether patients receive immunosuppressive therapy,” researchers wrote. However, they stressed that larger, controlled studies are needed to confirm its kidney-protective effects and long-term safety.
The study, “Efficacy and safety of finerenone in adults with IgA nephropathy: a 12-month real-world study,” was published in Renal Failure.
IgAN treatment includes therapies that help protect kidney function
IgAN is a chronic kidney disease and a leading cause of kidney failure caused by deposits of an abnormal form of the immunoglobulin A (IgA) antibody in the kidneys. These deposits trigger inflammation and damage the kidneys’ filtering units, allowing proteins that would normally remain in the bloodstream to leak into the urine.
Persistent proteinuria (more than 150 mg of protein in a 24-hour urine collection), reduced kidney function, and signs of kidney damage, such as scarring, are well-established risk factors for disease progression.
IgAN treatment includes therapies that help protect kidney function, such as renin-angiotensin system (RAS) inhibitors and SGLT2 inhibitors, along with immunosuppressive treatments for some people at high risk of disease progression.
“However, real-world data have demonstrated considerable [variability] in treatment outcomes, and many patients continue to experience persistent proteinuria and progressive kidney function decline despite these measures, underscoring the inadequacy of current therapeutic options and the need for novel therapeutic approaches,” the researchers wrote.
Finerenone has shown promising proteinuria-lowering effects
Finerenone is a medication that blocks the mineralocorticoid receptor protein, the overactivation of which promotes inflammation and fibrosis in the kidneys. It is approved in the U.S. under the brand name Kerendia to reduce the risk of kidney and heart complications in adults with chronic kidney disease associated with type 2 diabetes and the risk of serious cardiovascular events in certain adults with heart failure.
In people with diabetes-related chronic kidney disease, finerenone was shown to reduce proteinuria and slow kidney disease progression. Growing evidence of its off-label use suggests it may also benefit people with nondiabetic chronic kidney disease, including those with IgAN.
“Short-term real-world studies have shown promising proteinuria-lowering effects, but long-term data … on [kidney] function trajectory and efficacy independent of immunosuppression remain scarce,” the researchers wrote.
24-hour urine protein levels fell by a median of 29.7%
To evaluate the efficacy and safety of finerenone in IgAN patients, researchers in China retrospectively analyzed data from 52 adults with biopsy-confirmed IgAN who started finerenone between 2023 and 2025. All were followed at a single hospital and received the therapy for at least three months.
Participants’ mean age was 40.6, and 71.2% were women. Most (92.3%) received 10 mg of finerenone daily. The majority of participants were also taking other kidney-protective medications: 86.5% received RAS inhibitors, and 50% were taking SGLT2 inhibitors. Nine (17.3%) were also on immunosuppressive therapy, while the remaining 82.7% were not.
Data showed that median 24-hour urine protein levels fell from 750 mg before starting finerenone to 496 mg after one year, reflecting a median reduction of 29.7%. The decrease became statistically significant after six months and remained significant at one year. A similar pattern was seen among the 43 participants who were not receiving immunosuppressive therapy.
Kidney function also remained stable across all participants and those not on immunosuppressive treatment, with no significant changes in estimated glomerular filtration rate, a measure of how well the kidneys filter the blood. However, the researchers noted that a one-year follow-up is too short to determine whether finerenone can slow kidney function decline over time.
This study provides preliminary evidence that finerenone is associated with sustained proteinuria reduction and stable [kidney] function in patients with IgAN.
Among the 32 participants with at least 300 mg of urinary protein per day at the start of the study and available one-year data, five (15.6%) achieved complete remission, defined as 24-hour urine protein levels below 300 mg and stable kidney function. Another five (15.6%) achieved partial remission, defined as at least a 50% reduction in 24-hour urine protein with stable kidney function.
Among the 28 participants not receiving immunosuppressive therapy who met the same criteria, five (17.9%) achieved complete remission, and three (10.7%) achieved partial remission.
Finerenone was generally well tolerated. Two participants (3.8%) developed high blood potassium levels, a known side effect of the therapy. Both cases were managed with dietary changes or short-term medication, and neither required stopping finerenone.
No serious adverse events, cardiovascular events, acute kidney injury, or liver toxicity were reported.
“This study provides preliminary evidence that finerenone is associated with sustained proteinuria reduction and stable [kidney] function in patients with IgAN,” the team wrote.
Among the study’s limitations, the researchers noted its retrospective, single-center design, small sample size, and the lack of an untreated comparison group. Most participants were also taking other kidney-protective medications, making it difficult to determine how much of the observed benefit was specific to finerenone. In addition, only 39 participants had available one-year data.
“Future large-scale, multicenter, [appropriately controlled] trials with extended follow-up are warranted to further confirm the [kidney-protective] effects and safety of finerenone in IgAN,” the researchers wrote.
