Otsuka Holdings said the final 24-month analysis of its VISIONARY phase 3 trial found one composite kidney event among 259 patients given VOYXACT (sibeprenlimab), against 28 among 251 on placebo. The event is defined as kidney function decline or kidney failure. The company puts the relative risk reduction at 97.1%.
Otsuka's subsidiaries Otsuka Pharmaceutical and Otsuka Pharmaceutical Development & Commercialization presented the data on 22 October US time at the American Society of Nephrology's Kidney Week 2026 in Denver. The company says the results were published in The New England Journal of Medicine at the same time. This article relies on Otsuka's disclosure alone for the efficacy, safety and publication statements. For earlier two-year kidney function data, see Earlier Tokyo Brief coverage.
What the counts show
The trial randomised 510 adults with primary IgA nephropathy at risk of disease progression, in a double-blind, placebo-controlled design. Otsuka reports the composite event in 0.4% of the VOYXACT group and 11.2% of the placebo group. Each component of the composite also favoured VOYXACT.
| Measure | VOYXACT | Placebo |
|---|---|---|
| Composite kidney event (decline or failure) | 1 (0.4%) | 28 (11.2%) |
| Sustained eGFR decline of 40% or more | 1 | 28 |
| Sustained doubling of serum creatinine | 0 | 13 |
| Sustained eGFR below 15 mL/min/1.73 m² | 1 | 10 |
| Started renal replacement therapy | 0 | 5 |
Otsuka also reported a 61.3% reduction in the 24-hour urine protein-to-creatinine ratio at 24 months. Among patients with blood in the urine at baseline, 78.6% on VOYXACT tested negative by dipstick, against 20.2% on placebo. The company says VOYXACT is the first phase 3 IgA nephropathy therapy to meet the KDIGO 2025 guideline target of holding annual kidney function decline below 1 mL/min/1.73 m².
Safety
Otsuka describes the safety profile over 24 months as consistent and similar to placebo. Any adverse event occurred in 90.7% of the VOYXACT group and 90.0% of the placebo group. Injection-site reactions occurred in 35.1% and 32.3%. Serious infections were lower on VOYXACT, at 1.9% against 4.0%. The company says no new safety concerns emerged.
The regulatory step
VOYXACT won US accelerated approval in November 2025 for reducing proteinuria in adults with IgA nephropathy at risk of progression. With VISIONARY complete, Otsuka Pharmaceutical finished the staged submission of a supplemental biologics license application to the FDA on 6 October US time, seeking full approval. The disclosure gives no timeline for an FDA decision.
Otsuka left its consolidated forecast for the year to December 2026 unchanged. It calls VOYXACT one of the products expected to drive future growth and describes the results as important progress toward medium- to long-term value. An open-label long-term extension study (NCT05248659) is still running, and the company expects further data from it.