Associate Professor, Drexel University, Co-Director Autoimmune Kidney Disease Center, Allegheny Health Network

Swati Arora, MD

Rare Disease Day 2026: Kidney Diseases Enter Optimistic Therapeutic Era

On Rare Disease Day 2026, 4 clinicians share their insights and perspectives on the groundbreaking improvements in the rapidly evolving field of rare kidney diseases.

Despite persistent awareness gaps in rare kidney disease care, a wave of FDA approvals and phase 3 trial successes in 

 alongside updated 2025 KDIGO Practice Guidelines, has fueled growing clinician optimism about a rapidly advancing, disease-modifying treatment era.

Rare kidney diseases remain complex and underrecognized, leaving both patients and clinicians with challenges in early diagnosis, risk stratification, and long-term management. Yet recent scientific advances and regulatory approvals are beginning to reshape the therapeutic landscape.

Momentum in rare kidney disease care has accelerated with multiple FDA approvals supported by pivotal clinical trial data. In IgAN, 

demonstrated significant reductions in proteinuria and preservation of kidney function in the NefIgArd trial, while 

, a dual endothelin-angiotensin receptor antagonist, showed positive outcomes in the PROTECT study. The addition of 

, an endothelin A receptor antagonist, further underscores the diversification of therapeutic strategies in IgAN, with the ALIGN Phase III trial demonstrating clinically meaningful reductions in proteinuria, a key surrogate for slowing disease progression. Iptacopan, a factor B inhibitor targeting the alternative complement pathway, reported encouraging efficacy in the APPLAUSE-IgAN trial, highlighting a precision-based approach to treatment.

In C3G, iptacopan also showed promising results in the 

, alongside other complement-targeted therapies such as 

 and danicopan, reflecting growing opportunities for disease modification in a previously limited treatment space.

These advances are complemented by the updated 

, which provide evidence-based recommendations to support clinicians in diagnosis, monitoring, and treatment selection, fostering a more standardized and patient-centered approach.

Together, these therapies, spanning endothelin-angiotensin signaling modulation, complement inhibition, and targeted anti-inflammatory strategies, illustrate a shift toward precision medicine in rare kidney disease. 

6 New Kidney Disease Medications Approved in 2025. National Kidney Foundation. Published January 21, 2026. 

https://www.kidney.org/news-stories/6-new-kidney-disease-medications-approved-2025

Sayna Norouzi, MD, Cheung K, Skolnik E, Peleg Y. 2025 KDIGO Guideline Update for IgAN. Hcplive.com. Published January 14, 2026. Accessed February 28, 2026. https://www.hcplive.com/view/2025-kdigo-guideline-update-for-igan

Perkovic V, Barratt J, Rovin BH, et al; APPLAUSE‑IgAN Investigators. 

Alternative complement pathway inhibition with iptacopan in IgA nephropathy.

 N Engl J Med. 2025;392(6):531‑543. doi:10.1056/NEJMoa2410316. Published online 2024 Oct 25.

Kavanagh D, Bomback AS, Vivarelli M, et al. 

Oral iptacopan therapy in patients with C3 glomerulopathy: a randomized, double‑blind, placebo‑controlled, phase 3 study.

 Lancet. 2025;406(10512):1587‑1598. doi:10.1016/S0140‑6736(25)01148‑1.

Lafayette R, et al; NefIgArd Investigators. 

Efficacy and safety of a targeted‑release formulation of budesonide in patients with primary IgA nephropathy (NefIgArd): 2‑year results from a randomized phase 3 trial.

KDIGO IgAN and IgA Vasculitis Work Group; Rovin BH, Barratt J, Cook HT, et al. 

KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV).

 Kidney Int. 2025;108(4S):S1‑S71. doi:10.1016/j.kint.2025.04.004.

Novartis receives FDA accelerated approval for Fabhalta (iptacopan), the first and only complement inhibitor for reduction of proteinuria in adults with primary IgA nephropathy.

Novartis investigational atrasentan Phase III study demonstrates clinically meaningful proteinuria reduction in patients with IgA nephropathy (ALIGN).

Videos

On Rare Disease Day 2026, clinicians share their perspective on the evolving landscape for IgAN and C3G. 

Swati Arora, MD

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