Otsuka Reports “Unprecedented” Results for IgA Nephropathy Drug

Rare Daily Staff

Otsuka reported positive Phase 3 results for Voyxact that suggest the drug may slow disease progression to near-physiologic rates of decline.

The VISIONARY study showed two-year kidney function stabilization in adults with IgA nephropathy, with the drug’s eGFR results meeting the trial’s key secondary endpoint.

In the two-year analysis presented at GlomCon Hawaii 2026, the study found that people taking Voyxact kept their kidney function about the same, while people taking placebo saw kidney function decline. By the end of the study, the difference between the two groups was large enough to suggest Voyxact may help slow the disease’s impact on the kidneys.

Otsuka and the study investigators said the results are the first IgAN data to meet the international kidney disease nonprofit KDIGO’s evidence-based guideline goal of reducing kidney function loss to about the normal rate seen with aging. One doctor called that a major step forward, and Otsuka said the findings could help change how IgA nephropathy is treated.

IgA nephropathy, or IgAN, is a kidney disease that happens when a certain antibody builds up in the kidneys and causes inflammation and damage. Over time, that can make the kidneys leak protein into the urine and gradually lose their ability to filter blood properly, which can eventually lead to kidney failure.

Voyxact is delivered as a once-a-month injection for adults with primary IgA nephropathy who are at risk of their disease getting worse. It works by blocking APRIL, a protein involved in making the abnormal antibody believed to drive the disease, with the goal of reducing kidney damage over time.

The company said the safety profile remained comparable to placebo over 24 months, with no new safety signals identified. It reported similar overall adverse event rates, while serious infections were lower in the Voyxact arm than in placebo.

The new dataset completes the VISIONARY Phase 3 package and supports Otsuka’s rolling supplemental BLA submission to the FDA seeking traditional approval for Voyxact. Voyxact already has accelerated approval in the United States for reducing proteinuria in adults with primary IgAN at risk for progression, and the company says the new eGFR findings add to earlier data on proteinuria, hematuria and Gd-IgA1 reductions.