Otsuka Presents VISIONARY Two-Year eGFR Results Demonstrating Stabilisation of Kidney Function with sibeprenlimab in IgAN

• Phase 3 VISIONARY study results showed sibeprenlimab stabilised estimated glomerular filtration rate (eGFR), maintaining kidney function at baseline rate over two years1
• Sibeprenlimab is the first IgAN treatment to achieve the Kidney Disease Improving Global Outcomes (KDIGO) therapeutic goal of effectively halting progressive kidney function decline to the physiologic rate1,2
• VISIONARY is the largest Phase 3 study ever conducted in immunoglobulin A nephropathy (IgAN), a progressive chronic kidney disease which affects approximately 43 per 100,000 people across Europe3

Stockholm 2026-08-05, Otsuka, have announced two-year results from the Phase 3 VISIONARY study (NCT05248646) evaluating sibeprenlimab in adults with primary immunoglobulin A nephropathy (IgAN) at risk of disease progression.1 The results, presented during a late-breaking oral presentation at the GlomCon Hawaii 2026 conference, showed the use of sibeprenlimab stabilised estimated glomerular filtration rate (eGFR), a key measurement for healthcare professionals to understand kidney function.1

The results demonstrated VISIONARY’s key secondary endpoint with an annualised eGFR slope of +0.3 (95% CI, -0.4 to 0.9) mL/min/1.73 m²/year with sibeprenlimab versus -4.2 (95% CI, -4.9 to -3.6) mL/min/1.73 m²/year with placebo, demonstrating a treatment effect of +4.5 (95% CI, 3.6 to 5.4; p<0.0001) mL/min/1.73 m²/year at two years.1 The annualised eGFR slope was estimated using a linear mixed-effects model that evaluated repeated eGFR measurements from Week 4 through Week 104 to assess the annual rate of kidney function change.1

The overall safety profile of sibeprenlimab was comparable to placebo, with similar rates of overall adverse events (90.7% vs 90.0%), infections and infestations (51.4% vs 51.0%), and injection site pain (11.6% vs 10.8%).1 Rates of serious infections and infestations were lower with sibeprenlimab than placebo (1.9% vs 4.0%), alongside lower rates of serious treatment-related adverse events (TRAE) and severe treatment-emergent adverse events (TEAE), (0.8% vs 1.2%) and (3.9% vs 7.6%) respectively, and TEAEs leading to discontinuation of sibeprenlimab or placebo (1.2% vs 4.0%).1

VISIONARY is the largest Phase 3 study conducted to date in IgAN, enrolling approximately 510 participants across 31 countries. The two-year eGFR findings build on previously reported reductions in galactose-deficient IgA1 (Gd-IgA1), proteinuria and haematuria observed with sibeprenlimab.4

IgAN is a chronic kidney disease which occurs when immunoglobulin A (IgA) and abnormal antibodies such as Gd-IgA1 build up in the kidneys.5 This occurrence can generate inflammation which can make it more difficult for kidneys to function. Over time IgAN can lead to progressive loss of kidney function and, eventually, end-stage kidney disease (ESKD).5,6 Approximately 30% of those diagnosed with IgAN will lose kidney function and require a transplant or life on dialysis.7

Sibeprenlimab is a monoclonal antibody that selectively inhibits the activity of APRIL (A PRoliferation-Inducing Ligand).8 By inhibiting APRIL, sibeprenlimab may reduce immunoglobulin A (IgA) and the production of abnormal antibodies such as Gd-IgA1 which in turn may reduce kidney damage and potential progression towards ESKD.9,10,11

“We are encouraged by the continued results from the Phase 3 VISIONARY study. These two-year eGFR findings add to the growing body of evidence which highlight sibeprenlimab’s potential to halt kidney disease progression and stabilise kidney function in IgAN,” said Andy Hodge, President & CEO Otsuka Pharmaceutical Europe Ltd. “A full analysis of the VISIONARY study will be presented at an upcoming global scientific congress later this year. We look forward to continuing to work with the IgAN community and moving towards our goal of addressing the unmet need for patients living with this serious condition.”

In Europe, sibeprenlimab was granted orphan designation by the European Commission for the treatment of primary IgAN in 2021.12 In 2025, the treatment received U.S Food and Drug Administration (FDA) accelerated approval for reduction in proteinuria in adults with primary IgAN at risk of disease progression, becoming the first and only U.S FDA approved APRIL inhibitor.13

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About the VISIONARY Study
VISIONARY (NCT05248646) is a global, randomised, double-blind, placebo-controlled Phase 3 study evaluating the efficacy and safety of sibeprenlimab in adults with primary IgAN at risk for disease progression. The primary efficacy endpoint assessed proteinuria, as measured by the change in 24-hour urine protein-to-creatinine ratio (uPCR-24h) from baseline compared with placebo after nine months of treatment. The key secondary endpoint evaluates annualised glomerular filtration rate (eGFR) slope over 24 months (two years), providing an assessment of kidney function over time.

About sibeprenlimab
Sibeprenlimab is a monoclonal antibody that selectively binds to and inhibits APRIL (A PRoliferation-Inducing Ligand), which plays a key role in the 4-hit process.8,10 By selectively binding and inhibiting APRIL, sibeprenlimab may help reduce immunoglobulin A (IgA) and galactose-deficient IgA1 (Gd-IgA1) levels.9 Lower levels of Gd-IgA1 should provide less substrate for immune complex formation.10 Decreased immune complex formation should result in diminished deposition in the kidney, and reduced proteinuria and kidney inflammation.10,14

About IgAN and APRIL
IgAN is a progressive, immune-mediated, chronic kidney disease that typically manifests in adults aged 34-45 years and can lead to end-stage kidney disease (ESKD) over the lifetime of many patients.5,15 It is characterised by the deposition of Gd-IgA immune complexes in the kidneys. IgAN can lead to progressive loss of kidney function and, eventually, ESKD, imposing a significant burden on patients.5 Despite supportive care, there is an unmet need for treatments that address the root causes of the condition.6,10

APRIL, a cytokine in the tumour necrosis factor (TNF) family, is integral to the pathogenesis and progression of IgAN. It promotes the survival and class switching of B cells to produce IgA, including the pathogenic Gd-IgA1 that forms immune complexes in the kidneys.10,16

About Otsuka
Otsuka Pharmaceutical Co., Ltd. is a total healthcare company that focuses on each individual’s potential to enhance their well-being. Our medical-related business provides treatments and diagnostics for both physical and mental health. Our nutraceutical business supports daily health maintenance and improvement. Otsuka’s products and services are based on scientific evidence, under the guidance of our corporate philosophy: Otsuka-people creating new products for better health worldwide. Otsuka Europe employs around 500 people and focuses on psychiatric and neurologic disorders, nephrology and immunology, haemato-oncology, and digital therapeutics.

Otsuka Pharmaceutical Europe Ltd. is a part of Otsuka Pharmaceutical Company, Ltd., a subsidiary of Otsuka Holdings Co., Ltd. headquartered in Tokyo, Japan. For further information on Otsuka, please visit www.otsuka-europe.com.

Media Contact
Alison Ross
Otsuka Pharmaceutical Europe Ltd.
ARoss@Otsuka-Europe.com
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References
1 Rizk V.D et al. Sibeprenlimab in IgA Nephropathy: Topline 24-Month eGFR Results. Data Presentation, Glomcon, Hawaii 2026.
2 Kidney Disease: Improving Global Outcomes (KDIGO). Available at: https://kdigo.org/wp-content/u... Accessed August 2026.
3 Buisker J, et al. Clin. Kidney J. 2025;18(4): sfaf068.
4 Perkovic V, et al. N Engl J Med. 2026 394(7), 635–646.
5 Cheung CK, et al. Clin. Med. 2012;12(6): s27–s31.
6 Pitcher D, et al. Clin J Am Soc Nephrol. 2023;18(6):727-738.
7 Kidney Research UK. IgA nepgropathy (IgAN). Available at: https://www.kidneyresearchuk.o... Accessed August 2026
8 Mathur M, et al. N Engl J Med. 2024;390:20-31.
9 Mathur M, et al. Kidney Int Rep. 2022;7(5):993-1003.
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11 Chang S, et al. Front. Med. 2020; 7:92.
12 European Medicines Agency. Orphan designation for treatment of primary IgA nephropathy. Available at: https://www.ema.europa.eu/en/medicines/human/orphan-designations/eu-3-21-2444. Accessed August 2026.
13 FDA. FDA approves a new treatment for primary immunoglobulin A nephropathy. Available at: https://www.fda.gov/drugs/news-events-human-drugs/fda-approves-new-treatment-primary-immunoglobulin-nephropathy. Accessed August 2026.
14 Kant S, et al. Am J Kidney Dis. 2022;79(4):582-600.
15 Stoneman S, et al. JAMA. 2026;335(9):799-813
16 Hahne et al. J Exp Med. 1998 ;188(6):1185–1190