NICE Recommends FILSPARI® (sparsentan) for Routine Use in the NHS to Treat Adults with IgA Nephropathy, Marking a Significant Step Forward in Rare Kidney Disease Management
CSL Vifor has announced a major regulatory and reimbursement milestone for its innovative kidney disease treatment, sparsentan (marketed as FILSPARI®). The National Institute for Health and Care Excellence (NICE) has issued final draft guidance recommending the use of sparsentan within the National Health Service (NHS) in England. Specifically, the guidance supports its use as a treatment option for adult patients diagnosed with primary immunoglobulin A (IgA) nephropathy who exhibit elevated levels of protein in their urine — a key marker of disease severity and progression.
This decision is applicable to adults whose urine protein excretion reaches or exceeds 1.0 grams per day, or who have a urine protein-to-creatinine ratio of 0.75 grams per gram or more. These thresholds align with evidence demonstrating that such patients are at increased risk of disease progression and kidney failure. Importantly, NICE has stipulated that continued access to sparsentan should be contingent upon the patient demonstrating a response to the therapy. This outcome-focused condition ensures that NHS resources are directed toward patients who are likely to benefit most from the medication.
The NICE recommendation closely follows the regulatory approval of sparsentan by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA), which granted marketing authorization in April 2025. The timing of the guidance is notable, as it reflects the rapid pace at which this treatment has moved from regulatory clearance to potential patient access. In accordance with NHS policy, sparsentan must now be made available for eligible patients in England within 90 days of final publication of the NICE guidance. The publication date is anticipated to be June 27, 2025, which means NHS implementation could begin as early as late September 2025.
A Transformative Moment in IgA Nephropathy Treatment
The announcement has been widely welcomed by nephrologists and patient advocates alike. Professor Jonathan Barratt, Professor of Renal Medicine at the University of Leicester, emphasized the significance of the NICE endorsement in the broader context of managing IgA nephropathy. “IgA nephropathy is a condition with an average age at diagnosis of around 40 years. Due to disease progression, a patient’s kidneys may eventually fail. Treatments such as sparsentan, which have been specifically developed for IgA nephropathy, are urgently needed. Our goal is to improve outcomes and quality of life for these patients,” Professor Barratt said.
Sparsentan, a dual endothelin angiotensin receptor antagonist, offers a novel mechanism of action that simultaneously targets two critical pathways implicated in the development and progression of IgA nephropathy. This approach is believed to reduce proteinuria more effectively than traditional therapies, such as angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), which have been the mainstay of treatment for decades.
The NICE recommendation suggests that sparsentan offers a clinically meaningful benefit and represents a cost-effective use of NHS resources in the treatment of this patient population. By offering an additional treatment option for a rare but serious kidney disease, the decision opens the door to broader clinical use and could redefine the standard of care for thousands of individuals affected by the condition.
Understanding IgA Nephropathy and the Need for Innovation
IgA nephropathy, also known as Berger’s disease, is an autoimmune kidney disorder characterized by the accumulation of a defective form of immunoglobulin A (IgA) in the glomeruli — the small blood vessels within the kidney responsible for filtering waste from the blood. These deposits trigger inflammation and damage to the glomeruli, which eventually leads to leakage of blood (hematuria) and protein (proteinuria) into the urine. Left untreated or inadequately managed, this process can culminate in progressive kidney dysfunction and, ultimately, end-stage kidney disease (ESKD).
While IgA nephropathy is classified as a rare disease, it remains the most common form of primary glomerular disease worldwide. In England alone, an estimated 22,000 adults are currently living with the condition. The disease trajectory is highly variable, but the long-term outlook can be poor, especially for patients who exhibit persistent proteinuria. Clinical data indicate that 30% to 40% of patients progress to kidney failure within 10 years of diagnosis.
The disease burden is further compounded by the lack of curative therapies. Current treatment paradigms typically involve supportive care focused on controlling blood pressure and reducing proteinuria using ACE inhibitors or ARBs. However, these approaches do not work for everyone. Many patients continue to experience worsening proteinuria and are unable to delay progression to kidney failure despite optimal supportive care.
According to the most recent Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, patients who excrete more than 1 gram of protein per day in their urine — despite optimal supportive management — are considered to be at high risk of progressing to chronic kidney disease. This high-risk group represents a critical unmet need, one that sparsentan is specifically designed to address.
CSL Vifor’s Commitment to Advancing Kidney Care
The NICE recommendation for sparsentan underscores CSL Vifor’s ongoing commitment to developing innovative therapies for patients with serious and underserved kidney conditions. Dr. Vinicius Gomes De Lima, Head of Global Medical Affairs at CSL Vifor, expressed the company’s satisfaction with the regulatory milestone and its potential impact on patient care.
“We are very pleased that NICE recognised the value of our innovative therapy, which helps to address a clear unmet medical need in patients with IgA nephropathy,” Dr. De Lima said. “We look forward to working with the National Health Service to ensure access to this important medicine as soon as possible, as we continue to deliver on our promise to patients.”
Sparsentan’s development reflects years of focused research and clinical trial evaluation aimed at identifying a targeted solution for a disease with few therapeutic alternatives. Its approval and reimbursement in England represent not only a major commercial success for CSL Vifor but also a meaningful advance for nephrology patients and care providers.
As the NHS prepares to integrate sparsentan into clinical practice, attention will now turn to its implementation and the monitoring of real-world outcomes. With NICE’s conditional recommendation based on treatment response, physicians will play a key role in evaluating effectiveness and ensuring that therapy is aligned with individual patient benefit.
The wider nephrology community is likely to follow England’s lead, particularly in Europe and other jurisdictions where health technology assessment bodies look to NICE as a benchmark for reimbursement decisions. With the NICE guidance set to take effect by late June 2025, sparsentan could become a cornerstone in the future management of IgA nephropathy, helping to shift the treatment paradigm toward earlier, more effective interventions that aim to preserve kidney function and delay the onset of kidney failure.
As patients, clinicians, and health systems continue to grapple with the challenges posed by chronic kidney disease, the introduction of sparsentan offers a timely and potentially transformative solution — one that underscores the importance of innovation, evidence-based policymaking, and patient-centered care.
