Biogen presents 76-week EMPAVELI kidney data at ASN 2026
Biogen has taken a broad nephrology portfolio to the American Society of Nephrology Kidney Week in Denver, headlined by new 76-week data from its Phase 3 programme for EMPAVELI (pegcetacoplan) in two rare complement-driven kidney diseases: C3 glomerulopathy (C3G) and primary immune-complex membranoproliferative glomerulonephritis (IC-MPGN).
Two oral presentations will report that proteinuria reduction and estimated glomerular filtration rate (eGFR) stabilisation, both seen at earlier timepoints, were sustained through 76 weeks of treatment, with a consistent long-term safety profile. The readout is notable partly because the FDA recently expanded EMPAVELI's label to cover reduction of kidney function loss, making it, according to Biogen, the only approved therapy addressing both proteinuria and functional decline in patients with C3G and primary IC-MPGN aged 12 and above.
Felzartamab moves closer to Phase 3 readouts
Alongside the pegcetacoplan data, Biogen will present material on felzartamab, an investigational anti-CD38 monoclonal antibody acquired through its absorption of Apellis and licensed from MorphoSys (now a Novartis subsidiary). The company is studying felzartamab across four trials: three Phase 3 studies targeting antibody-mediated rejection (AMR) in kidney transplant recipients (TRANSCEND), IgA nephropathy (PREVAIL), and primary membranous nephropathy (PROMINENT), plus a Phase 2 trial in microvascular inflammation. Topline data from the TRANSCEND AMR study are expected in the first half of 2027, which will represent an early test of the CD38 mechanism in transplant immunology.
Daniel Quirk, chief medical officer at Biogen, said the ASN data "further reinforce EMPAVELI's long-term efficacy and safety profile, while new scientific insights highlight the significant unmet needs and lack of proven therapies in AMR." He added that the company's nephrology research now spans seven distinct kidney diseases.
Poster sessions will also address physician-reported gaps in AMR treatment, the humanistic and epidemiological burden of focal segmental glomerulosclerosis (FSGS), and pharmacokinetic and exposure-response analyses for pegcetacoplan, signalling Biogen's intent to position itself across a range of immune-mediated nephrology indications rather than rely on a single asset.
Competitive and regulatory context
The rare glomerular disease market has historically been underdrugged, but is becoming more competitive. Novartis's iptacopan, another complement inhibitor targeting the alternative pathway, won FDA approval in 2024 for PNH and has IgAN ambitions, while a number of smaller biotechs are pursuing proximal-complement and anti-FcRn approaches in membranous nephropathy and related conditions. Biogen's dual bet on upstream complement blockade with pegcetacoplan and plasma-cell depletion with felzartamab reflects a strategy of covering multiple immunological nodes in kidney disease rather than concentrating on a single mechanism.
For felzartamab specifically, the CD38 target is well-validated in haematological malignancies through daratumumab (Darzalex, Johnson and Johnson), but its application to autoimmune kidney disease remains unproven at Phase 3 scale. The TRANSCEND H1 2027 readout will therefore be closely watched by transplant nephrologists and investors alike. C3G and primary IC-MPGN together affect only a small patient population, underscoring the commercial importance of label expansion and the potential significance of FSGS data as a broader market opportunity for pegcetacoplan.