Biogen Announces Publication Of Phase 3 VALIANT Adolescent Subgroup Data In CJASN Demonstrating 75% Proteinuria Reduction For EMPAVELI In Rare Kidney Diseases

EMPAVELI-treated adolescents achieved a 75% relative reduction in proteinuria within 6 months versus placebo EMPAVELI is the only approved treatment for adolescents with C3G and primary IC-MPGN, based on VALIANT studyPublication follows a recent FDA label update to expand EMPAVELI’s indication to include reducing the loss of kidney function in patients 12 years and older, in addition to reducing proteinuria CAMBRIDGE, Mass., Sept. 17, 2026 (GLOBE NEWSWIRE) -- Biogen Inc. (NASDAQ:BIIB) today announced the publication of results from a prespecified adolescent subgroup analysis of the Phase 3 VALIANT study evaluating EMPAVELI® (pegcetacoplan) in the Clinical Journal of the American Society of Nephrology (CJASN). The dedicated subgroup analysis was first presented at the 2025 Annual Meeting of the European Society of Paediatric Nephrology (ESPN)."C3G and primary IC-MPGN are often diagnosed early in life, when preventing progressive kidney damage can have a meaningful long-term impact," said Bradley Dixon, M.D., Section Chief of Pediatric Nephrology and Professor of Pediatrics, University of Colorado School of Medicine and Children's Hospital Colorado. "The VALIANT results show substantial reductions in proteinuria and stabilization of kidney function in adolescents, consistent with what we observed in the broader population. These findings are especially encouraging for young patients who may otherwise face a lifetime of progressive kidney disease leading to a potential kidney transplant."The analysis showed that a cohort of adolescents aged 12 to 17 years with C3 glomerulopathy (C3G) or primary immune complex membranoproliferative glomerulonephritis (IC-MPGN) treated with EMPAVELI achieved clinically meaningful reductions in proteinuria and stabilization of kidney function compared with placebo. The findings were consistent with results from the overall VALIANT population.Adolescents represented nearly half of the VALIANT study population, providing one of the largest randomized datasets in this age group for C3G and primary IC-MPGN.Among the adolescent cohort (n= 55) at Week 26, results included:EMPAVELI-treated adolescents achieved a 75% relative reduction in proteinuria versus placebo (95% CI: 59%-84%; nominal p71% of adolescents treated with EMPAVELI achieved at least a 50% reduction in proteinuria, compared with 4% receiving placebo (nominal p57% of EMPAVELI-treated adolescents achieved both stable kidney function and at least a 50% reduction in proteinuria, compared with 4% receiving placebo (nominal p=0.002). The publication follows the recent FDA-approved label expansion for EMPAVELI, making it the first and only therapy approved to reduce both proteinuria and the loss of kidney function in adults and adolescents aged 12 years and older. The label update was based on 52-week efficacy and safety data from the VALIANT study demonstrating substantial reductions in proteinuria and sustained preservation of kidney function, as measured by estimated glomerular filtration rate (eGFR)."The results published in the Clinical Journal of the American Society of Nephrology further strengthen our confidence in the benefits EMPAVELI can provide for adolescents living with C3G and primary IC-MPGN," said Daniel Jones, Ph.D., Vice President, Head of Global Medical Affairs for EMPAVELI at Biogen. "Together with the recent expansion of the U.S. indication for EMPAVELI, these findings reinforce the potential for EMPAVELI to help protect patients’ kidney health."EMPAVELI was well tolerated in adolescents, with a safety profile consistent with the overall VALIANT population.