Novartis’ kidney disease drug Fabhalta receives US FDA approval

Novartis announced that the US FDA has granted accelerated approval for Fabhalta (iptacopan), a first-in-class complement inhibitor for the reduction of proteinuria in adults with primary immunoglobulin A nephropathy (IgAN) at risk of rapid disease progression. This is generally defined as a urine protein-to-creatinine ratio (UPCR) ≥1.5 g/g (1). Fabhalta specifically targets the alternative complement pathway of the immune system. When overly activated in the kidneys, the complement system is thought to contribute to the pathogenesis of IgAN (1-4).

This indication is granted under accelerated approval based on the pre-specified interim analysis of the Phase III APPLAUSE-IgAN study measuring reduction in proteinuria at 9 months compared to placebo. It has not been established whether Fabhalta slows kidney function decline in patients with IgAN. The continued approval of Fabhalta may be contingent upon verification and description of clinical benefit from the ongoing Phase III APPLAUSE-IgAN study, evaluating whether Fabhalta slows disease progression as measured by estimated glomerular filtration rate (eGFR) decline over 24 months (1). The eGFR data are expected at study completion in 2025 and are intended to support traditional FDA approval.

IgAN is a progressive, rare disease in which the immune system attacks the kidneys, often causing glomerular inflammation and proteinuria (12). Approximately 25 people per million worldwide are newly diagnosed with IgAN each year13. Each person’s disease journey is unique as IgAN progresses differently and treatment responses vary as well (12,14).

Despite the current standard of care, up to 50 per cent of IgAN patients with persistent proteinuria progress to kidney failure within 10 to 20 years of diagnosis. These patients often require maintenance dialysis and/or kidney transplantation5-11. Effective, targeted therapies with different mechanisms of action can help physicians select the most appropriate treatment for patients (12,14).

Data supporting approval
The ongoing Phase III APPLAUSE-IgAN study is evaluating the efficacy and safety of twice-daily oral Fabhalta (200 mg) versus placebo in adult IgAN patients on a stable dose of maximally-tolerated renin-angiotensin system (RAS) inhibitor therapy with or without a stable dose of SGLT2i. The primary endpoint for the interim analysis was the per cent reduction of proteinuria, a marker of kidney damage, measured by comparing UPCR at 9 months to baseline (1,4).

Fabhalta achieved a 44 per cent reduction in proteinuria at 9 months relative to baseline, compared with a 9per cent reduction in the placebo arm, demonstrating a clinically meaningful and statistically significant 38 per cent reduction vs. placebo (p<0.0001). The treatment effect on UPCR at 9 months was consistent across all subgroups, including age, sex, race and baseline disease characteristics (such as baseline eGFR and proteinuria levels), and the use of SGLT2i1. Fabhalta demonstrated a favourable safety profile, consistent with previously reported data (1,13). In patients with IgAN, the most common adverse reactions (≥5 per cent) with Fabhalta were upper respiratory tract infection, lipid disorder, and abdominal pain. Fabhalta may cause serious infections caused by encapsulated bacteria and is available only through a Risk Evaluation and Mitigation Strategy (REMS) that requires specific vaccinations (1).

References:

1. FABHALTA prescribing information. East Hanover, NJ: Novartis Pharmaceuticals Corp; August 2024.
2. Lafayette RA, Kelepouris E. lmmunoglobulin A nephropathy: advances in understanding of pathogenesis and treatment. Am J Nephrol. 2018;47(suppl 1):43-52.
3. Rizk DV, Maillard N, Julian BA, et al. The emerging role of complement proteins as a target for therapy of IgA nephropathy. Front Immunol. 2019;10:504.
4. Perkovic V, Kollins D, Renfurm R, et al. Efficacy and Safety of Iptacopan in Patients with IgA Nephropathy: Interim Results from the Phase 3 APPLAUSE-IgAN Study. Presented at the World Congress of Nephrology (WCN); April 15, 2024; Buenos Aires, Argentina.
5. Xie J et al. PLoS One. 2012;7;e38904.
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12. Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int. 2021;100(4):S1-S276.
13. Zhang H, Rizk DV, Perkovic V, et al. Results of a Randomized Double-Blind Placebo-Controlled Phase 2 Study Propose Iptacopan as an Alternative Complement Pathway Inhibitor for IgA Nephropathy. Kidney Int. 2024;105(1):189-199.
14. Boyd JK, Cheung CK, Molyneux K, Feehally J, Barratt J. An Update on the Pathogenesis and Treatment of IgA Nephropathy. Kidney Int. 2012;81(9):833-843.