AstraZeneca posts positive Phase III Ultomiris data in IgA nephropathy
Bottom line
AstraZeneca said Ultomiris, its long-acting C5 complement inhibitor, met the primary endpoint in a prespecified interim analysis of the Phase III I CAN trial in adults with IgA nephropathy at risk of disease progression. In results announced April 21, 2026, the drug showed a statistically significant and clinically meaningful reduction in proteinuria at week 34 versus placebo, with an effect seen as early as week 10. The study is still ongoing, and the kidney function endpoint, change in eGFR, will be assessed at week 106. AstraZeneca said no new safety concerns were identified and that it plans to seek accelerated approval in key markets. (news.cision.com)
Why it matters: For veterinary professionals tracking translational medicine and renal immunology, this is another sign that complement-targeted therapies are moving deeper into chronic kidney disease, not just rare hematologic or neurologic disorders. IgA nephropathy treatment is becoming more crowded, with multiple late-stage or recently approved agents targeting different pathways, including complement, endothelin, and APRIL/BAFF biology. That makes Ultomiris notable less because the interim proteinuria result is definitive on its own, and more because it adds another mechanism that could reshape how kidney disease progression is managed if the eGFR data hold up. (news.cision.com)
What to watch: The key next step is the week 106 eGFR readout, which will show whether the proteinuria benefit translates into durable kidney function preservation and supports regulatory filings beyond accelerated pathways. (news.cision.com)
Key facts
- Drug
- Ultomiris (ravulizumab)
- Indication
- IgA nephropathy in adults at risk of disease progression
- Trial
- Phase III I CAN
- Primary endpoint
- Met at week 34
- Key finding
- Reduced proteinuria versus placebo, with effect seen as early as week 10
- Kidney function endpoint
- Change in eGFR at week 106
- Safety
- No new safety concerns identified
- Announcement date
- April 21, 2026
- Regulatory plan
- Plans to seek accelerated approval in key markets
AstraZeneca has reported positive interim Phase III data for Ultomiris in IgA nephropathy, saying the drug reduced proteinuria versus placebo in the I CAN trial and hit its primary endpoint at week 34. The company announced the result on April 21, 2026, positioning ravulizumab as a potential disease-modifying option in a fast-evolving IgA nephropathy market. AstraZeneca also said the effect emerged as early as week 10, no new safety signals were seen, and filings for accelerated approval are planned in key regions. (news.cision.com)
The result builds on a broader shift in IgA nephropathy treatment, where proteinuria reduction has become an important early marker for regulatory and clinical decision-making, even though long-term kidney function remains the harder endpoint that ultimately matters most. KDIGO’s 2025 guideline update emphasized tighter proteinuria control and a more proactive treatment approach for patients at risk of progression. At the same time, several companies have advanced targeted agents in IgA nephropathy, reflecting growing confidence that pathway-specific therapies may alter the course of disease more effectively than supportive care alone. (kdigo.org)
In I CAN, adults with IgA nephropathy on stable standard-of-care background therapy were randomized 1:1 to intravenous Ultomiris or placebo for 106 weeks. According to AstraZeneca, the trial was designed to enroll about 510 participants across 28 countries. The interim analysis focused on change from baseline in 24-hour urine protein-creatinine ratio at week 34, while the final analysis will assess change in eGFR at week 106. Key secondary endpoints include at least 50% reduction in proteinuria at week 34, proteinuria change at week 10, sustained eGFR decline, and composite kidney outcomes. (news.cision.com)
Mechanistically, the story is important because Ultomiris targets terminal complement C5, a downstream point in the complement cascade. AstraZeneca argues that terminal complement activation is a central driver of kidney inflammation in IgA nephropathy. That complements prior mid-stage evidence: a published Phase II trial of ravulizumab in IgA nephropathy reported reductions in proteinuria and supported continued development of the program, although the field has been waiting for larger, registrational data to clarify whether biomarker gains will translate into preserved kidney function over time. (news.cision.com)
Outside AstraZeneca, the competitive context is getting more intense. Novartis has already reported positive Phase III data for Fabhalta in IgA nephropathy and said those results support a 2026 submission for traditional FDA approval after an earlier accelerated approval based on proteinuria reduction. ICER’s 2026 review of IgA nephropathy therapies also underscored both the progress in the field and the remaining uncertainty around long-term outcomes and value. In other words, Ultomiris is entering a market that is no longer defined by unmet need alone, but by growing pressure to prove durability, differentiation, and practical fit in care pathways. (novartis.com)
AstraZeneca did provide one outside expert comment in its release. Jonathan Barratt, a University of Leicester renal medicine professor and I CAN investigator, said many patients with IgA nephropathy still progress to kidney failure despite advances in care, and that blocking terminal complement activation with Ultomiris may have a promising role in reducing proteinuria. Broader nephrology commentary has echoed that complement inhibition is one of several plausible strategies, but not necessarily the only answer, and that future care may involve layered or combination approaches if safety, cost, and access can support them. (news.cision.com)
Why it matters: For veterinary professionals, the direct clinical relevance is limited because this is a human renal disease program, but the translational signal is worth noting. Complement biology is increasingly central across inflammatory and immune-mediated disorders, and renal drug development is moving toward mechanism-based, biomarker-driven strategies that may eventually inform comparative thinking in veterinary nephrology and immunology. The bigger lesson is that chronic kidney disease is becoming a precision-therapy space, with regulators and companies willing to act on earlier surrogate markers while still demanding longer-term functional confirmation. (news.cision.com)
What to watch: The biggest milestone is the final week 106 eGFR analysis, because that will determine whether Ultomiris can move from a promising proteinuria story to a stronger kidney-protection claim. Also worth watching are any detailed data presentations at medical meetings, the exact regulatory strategy for accelerated approval, and how AstraZeneca positions an intravenous every-eight-weeks therapy against increasingly competitive oral and biologic options in IgA nephropathy. (news.cision.com)