A clinical trial found that the drug atacicept lowered proteinuria (protein in the urine) by 46 percent in adults with immunoglobulin A nephropathy (IgAN), a type of chronic kidney disease. Proteinuria can be a sign of kidney damage, and reducing it may help slow disease progression.

Proteinuria can occur when the kidneys’ glomeruli (filters) are damaged and allow proteins that should stay in the blood to pass into urine. Proteinuria can lead to serious complications, including kidney failure and heart failure. In IgAN, proteinuria is a key marker of disease severity, and lowering protein levels in the urine is often a major treatment goal.

What Researchers Found

Atacicept is a once-weekly injection that blocks two proteins, known as BAFF and APRIL, which help immune cells called B cells survive and produce antibodies. In autoimmune kidney diseases like IgAN, these antibodies can damage kidney filters. By targeting BAFF and APRIL, atacicept aims to reduce harmful antibodies and inflammation.

In the phase 3 trial, 431 adults with IgAN were randomly assigned to receive atacicept or placebo (inactive treatment) for 36 weeks. People taking atacicept had a 42 percent greater reduction in proteinuria compared with those taking the placebo. The drug was as safe as the placebo. The trial will continue to track long-term kidney function.

A Potential Two-Prong Treatment for Proteinuria

The drug manufacturer Vera Therapeutics plans to submit an application to the U.S. Food and Drug Administration (FDA) later this year with the hopes of final approval coming in 2026. If approved, atacicept would be the first dual BAFF/APRIL inhibitor for IgAN.

Current treatments for proteinuria include medications such as ACE inhibitors, angiotensin-receptor blockers, SGLT2 inhibitors, and, for some, immunosuppressive drugs. Atacicept’s approach is different because it directly targets immune pathways thought to drive IgAN — potentially offering an option for people who still have high proteinuria despite standard therapy.

While new treatments are in development, there are strategies you might discuss with your doctor to help manage proteinuria and kidney health. These include:

• Taking your prescribed medications — such as blood pressure or diabetes drugs — exactly as directed
• Limiting salt intake to help control blood pressure
• Eating a balanced diet and avoiding excess protein unless your doctor recommends otherwise
• Staying active with regular, gentle exercise
• Avoiding nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen unless approved by your healthcare provider, as they can affect kidney function
• Getting regular urine and blood tests to monitor changes in kidney health

Always talk to your doctor before making changes to your treatment plan or diet.

Learn about five urine changes that can occur in kidney disease.

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Do you track your protein levels? What changes have helped you keep them under control? Let others know in a comment below.