--- title: "Felzartamab | PepTracker Pro" url: https://peptrackerpro.com/peptides/felzartamab description: "Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." lang: en --- Skip to main content **Educational information only.** This site does not provide medical advice. Read full disclaimer (https://peptrackerpro.com/disclaimer) **Research-only content.** This page is for educational purposes and does not constitute medical advice. Read full disclaimer → (https://peptrackerpro.com/research-disclaimer) # Felzartamab Medium Evidence Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical. Aliases Felzartamab +6 more Evidence Medium Evidence Last Updated 2026-09-19 Reading Time 7 min ## What It Is Felzartamab (MOR202/TJ202) is a fully human IgG1 monoclonal antibody directed against CD38, a transmembrane glycoprotein and ectoenzyme expressed most strongly on mature plasma cells, plasmablasts and a subset of natural killer (NK) cells. By binding CD38, felzartamab depletes these antibody-secreting cells through immune mechanisms such as antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and apoptosis. The therapeutic idea is 'upstream' immunology: many kidney diseases are driven by pathogenic antibodies (autoantibodies or alloantibodies), and depleting the plasma cells that produce them can lower those antibodies at their source rather than merely neutralizing them in the blood. This distinguishes felzartamab from APRIL/BAFF-directed agents (sibeprenlimab, povetacicept) that starve B cells of survival signals, and from FcRn blockers (efgartigimod, nipocalimab, rozanolixizumab, batoclimab) that accelerate clearance of circulating IgG. Felzartamab is administered as an intravenous infusion in time-limited courses. Its most advanced applications are three antibody-mediated kidney diseases. In IgA nephropathy (IgAN), the mucosal plasma cells overproduce galactose-deficient IgA1 (Gd-IgA1), whose immune complexes deposit in the kidney; the Phase 2a IGNAZ study (NCT05065970) showed rapid, durable proteinuria reductions, and the Phase 3 PREVAIL trial (NCT06935357) is randomizing about 454 patients to felzartamab or placebo with a primary endpoint of percent change in proteinuria (urine protein-to-creatinine ratio, UPCR) at Week 36. In primary membranous nephropathy (PMN), autoantibodies against the podocyte antigen PLA2R (anti-PLA2R) damage the kidney's filter; the Phase 1b/2a M-PLACE study (31 patients, a nine-dose course) reported anti-PLA2R titer reductions of at least 50% in about 77% of evaluable patients, supported by the NewPLACE study, earning FDA Breakthrough Therapy designation and a Phase 3 program. In late antibody-mediated rejection (AMR) of a transplanted kidney - a setting with essentially no approved therapy - a Phase 2 trial published in the New England Journal of Medicine showed improvements in rejection activity and biomarkers, and the Phase 3 TRANSCEND trial is now underway. Felzartamab originated at MorphoSys AG (MOR202), was in-licensed by HI-Bio in 2022, came to Biogen through its 2024 acquisition of HI-Bio, and Biogen acquired the Greater China rights from TJ Biopharma in 2026. Also known as: Felzartamab, MOR202, MOR03087, TJ202, anti-CD38 antibody, CD38-targeting monoclonal antibody, plasma cell-depleting antibody ## Regulatory Status Investigational - Phase 3 (not approved for kidney disease) Felzartamab (MOR202/MOR03087; TJ202 in Greater China) is an investigational fully human IgG1 anti-CD38 monoclonal antibody and is not approved for kidney disease by the FDA or any other regulatory agency. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Biogen (which obtained felzartamab through its 2024 acquisition of Human Immunology Biosciences and consolidated the Greater China rights from TJ Biopharma in 2026) is advancing three Phase 3 programs in rare antibody-mediated kidney diseases: PREVAIL (NCT06935357) in IgA nephropathy, randomizing about 454 patients to felzartamab or placebo with a primary endpoint of percent change in proteinuria (UPCR) at Week 36; a Phase 3 study in primary membranous nephropathy; and TRANSCEND, a Phase 3 study in late antibody-mediated rejection of a kidney transplant. Earlier evidence came from the Phase 2a IGNAZ study in IgA nephropathy (published in Kidney International), the Phase 1b/2a M-PLACE and Phase 2a NewPLACE studies in membranous nephropathy, and a Phase 2 AMR trial published in the New England Journal of Medicine. The related anti-CD38 antibody heritage includes daratumumab and isatuximab, which are approved in multiple myeloma; felzartamab (as TJ202) has also been developed in Greater China for multiple myeloma. As an investigational prescription biologic it is given by intravenous infusion under medical supervision within clinical trials, and is not a supplement, nootropic or research chemical. ## Why Researchers Study It Researchers study felzartamab because it tests a distinctive strategy for antibody-driven disease: instead of neutralizing a harmful antibody after it is made or blunting a single downstream signal, deplete the plasma cells that produce the antibody in the first place. CD38 is densely expressed on these antibody-secreting cells, and anti-CD38 antibodies are already validated in cancer (daratumumab, isatuximab in multiple myeloma), so felzartamab offered a way to bring that mechanism to autoimmune and alloimmune kidney disease. The kidney is an especially compelling proving ground because several of its most damaging diseases are unambiguously antibody-mediated: in IgA nephropathy, plasma cells overproduce galactose-deficient IgA1 that forms kidney-clogging immune complexes; in primary membranous nephropathy, autoantibodies against the podocyte protein PLA2R attack the filtration barrier; and in late antibody-mediated rejection, a transplanted kidney is injured by donor-specific antibodies - a setting with essentially no approved therapy. If depleting plasma cells with a time-limited infusion course can lower these pathogenic antibodies and translate into durable reductions in proteinuria, preserved kidney function and better graft survival, felzartamab could establish plasma-cell depletion as a broadly useful, mechanism-based approach across antibody-mediated diseases - and clarify how it compares with APRIL/BAFF blockade and FcRn inhibition, the other pillars of the new immunology toolkit. ## Proposed Mechanisms - CD38 targeting: felzartamab is a fully human IgG1 monoclonal antibody that binds CD38, a transmembrane glycoprotein and ectoenzyme expressed at high density on mature plasma cells, plasmablasts and a subset of NK cells. - Plasma-cell depletion: by engaging CD38, felzartamab depletes antibody-secreting cells through antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), complement-dependent cytotoxicity and direct apoptosis, reducing the cells that manufacture pathogenic antibodies. - Upstream, source-level control of pathogenic antibodies: depleting the plasma-cell 'factory' lowers autoantibodies and alloantibodies at their source - for example galactose-deficient IgA1 (Gd-IgA1) in IgA nephropathy, anti-PLA2R autoantibodies in primary membranous nephropathy, and donor-specific antibodies in transplant rejection - rather than merely neutralizing or clearing antibody already in the circulation. - Time-limited dosing: felzartamab is given as an intravenous infusion over defined treatment courses (for example roughly five to nine doses) rather than continuously, with the aim of resetting pathogenic antibody production and achieving durable responses after treatment ends. - Mechanistically distinct from other immunology biologics: unlike APRIL/BAFF inhibitors (sibeprenlimab, povetacicept) that withdraw B-cell survival signals, or FcRn blockers (efgartigimod, nipocalimab, rozanolixizumab, batoclimab) that speed IgG clearance, felzartamab removes the antibody-producing cells themselves. ## Evidence Snapshot Medium Evidence Low Medium High | Study Type | Model | Outcome | Link | | --- | --- | --- | --- | | Phase 2a randomized, double-blind, placebo-controlled trial in IgA nephropathy (IGNAZ; NCT05065970), published in Kidney International. | Adults with biopsy-confirmed IgA nephropathy and persistent proteinuria despite optimized supportive care, randomized to felzartamab (intravenous, time-limited course) or placebo, with proteinuria (UPCR) and pathogenic antibody markers followed during and after treatment. | Felzartamab produced rapid reductions in proteinuria that were sustained at nine months and persisted at around 18 months after treatment ended, with a safety profile consistent with the anti-CD38 class; these Phase 2a results supported advancing to the Phase 3 PREVAIL trial. | Source | | Phase 1b/2a open-label proof-of-concept study in primary membranous nephropathy (M-PLACE), supported by the Phase 2a NewPLACE study. | 31 adults with anti-PLA2R autoantibody-positive primary membranous nephropathy (newly diagnosed, relapsed or refractory to prior immunotherapy) treated with a five-month, nine-dose felzartamab course; primary focus on anti-PLA2R titer reduction and safety. | Immunologic response (anti-PLA2R titer reduction of at least 50%) was achieved by about 77% of efficacy-evaluable patients (20 of 26), with proteinuria remissions observed including in patients with high baseline titers or prior treatment failure. Felzartamab holds FDA Breakthrough Therapy designation in primary membranous nephropathy, and a Phase 3 study has been initiated. | Source | | Phase 2 randomized, double-blind, placebo-controlled trial in late antibody-mediated rejection (AMR) of a kidney transplant, published in the New England Journal of Medicine. | Kidney transplant recipients with late antibody-mediated rejection (occurring at least ~180 days after transplant) randomized to felzartamab or placebo, with rejection activity on biopsy and molecular/antibody biomarkers as key measures. | Felzartamab showed a potential therapeutic benefit - improvements in rejection activity and associated biomarkers - with an acceptable safety and adverse-event profile, in a disease that currently has no approved therapy. These results support the ongoing Phase 3 TRANSCEND program. | Source | ## Commonly Discussed Benefits renal: https://peptrackerpro.com/benefits/renal autoimmune: https://peptrackerpro.com/benefits/autoimmune Disease Modification: https://peptrackerpro.com/benefits/disease-modification B-cell-modulation: https://peptrackerpro.com/benefits/B-cell-modulation Researching Felzartamab? Track it, set reminders, and keep notes in the free app. Track in App (https://app.peptrackerpro.com/?add=felzartamab) ## Safety & Cautions - Felzartamab is an investigational anti-CD38 antibody that is NOT approved for kidney disease by the FDA or any other regulator. It should only be received within a clinical trial or other supervised medical setting; any product sold as 'felzartamab', 'MOR202' or 'TJ202' outside a legitimate clinical trial is unverified, unapproved and unsafe. - Because felzartamab depletes antibody-producing plasma cells, it can lower immunoglobulin levels, blunt responses to vaccines and raise the risk of infection. Live vaccines are generally avoided during treatment, and clinicians monitor for infections. (Studies to date, including in IgAN, have examined preservation of humoral immunity and vaccine responses, but infection risk remains a class consideration for plasma-cell-depleting therapy.) - As an intravenous antibody, felzartamab can cause infusion-related reactions, particularly with the first doses; infusions are given with monitoring and, where appropriate, premedication. - CD38 is also present on some blood and immune cells, and anti-CD38 antibodies as a class can interfere with certain blood-bank cross-matching tests and can affect blood counts; these are managed within specialist care. - Felzartamab's evidence so far rests largely on antibody and proteinuria biomarkers (for example anti-PLA2R titers in membranous nephropathy and UPCR in IgA nephropathy) over relatively short courses; long-term kidney-function (eGFR) outcomes and durability are still being established in the Phase 3 program. - This is a prescription biologic used under nephrology or transplant care alongside standard therapy (such as RAS blockade and SGLT2 inhibitors in glomerular disease); it is NOT a supplement, nootropic or research chemical and should never be self-sourced. ## Comparisons See how Felzartamab compares to related peptides: Felzartamab vs Batoclimab: https://peptrackerpro.com/compare/felzartamab-vs-batoclimab Felzartamab vs Efgartigimod: https://peptrackerpro.com/compare/felzartamab-vs-efgartigimod Felzartamab vs Nipocalimab: https://peptrackerpro.com/compare/felzartamab-vs-nipocalimab Felzartamab vs Rozanolixizumab: https://peptrackerpro.com/compare/felzartamab-vs-rozanolixizumab Felzartamab vs Povetacicept: https://peptrackerpro.com/compare/felzartamab-vs-povetacicept Felzartamab vs Sibeprenlimab: https://peptrackerpro.com/compare/felzartamab-vs-sibeprenlimab Felzartamab vs Atacicept: https://peptrackerpro.com/compare/felzartamab-vs-atacicept ## Calculator Tools Use our research tools to explore dosing and reconstitution data: Reconstitution Calculator: https://peptrackerpro.com/calculators ## Citations 1. [1] Biogen Highlights the Potential of Felzartamab for a Range of Immune-Mediated Diseases Including Three Phase 3 Programs in Rare Kidney Diseases - Biogen PubMed (https://investors.biogen.com/news-releases/news-release-details/biogen-highlights-potential-felzartamab-range-immune-mediated) 2. [2] Randomized, double-blind, placebo-controlled phase 2a study assessing the efficacy and safety of felzartamab for IgA nephropathy (IGNAZ) - Kidney International PubMed (https://www.kidney-international.org/article/S0085-2538(25)00488-0/fulltext) 3. [3] Biogen Initiates Phase 3 Study of Felzartamab for the Treatment of Primary Membranous Nephropathy - Biogen PubMed (https://investors.biogen.com/news-releases/news-release-details/biogen-initiates-phase-3-study-felzartamab-treatment-primary) 4. [4] Phase 1b/2a Study Assessing the Safety and Efficacy of Felzartamab in Anti-PLA2R Autoantibody-Positive Primary Membranous Nephropathy (M-PLACE) - Kidney International Reports PubMed (https://www.sciencedirect.com/science/article/pii/S2468024924017947) 5. [5] Biogen Initiates Phase 3 Study of Felzartamab for the Treatment of Late Antibody-Mediated Rejection (AMR) in Kidney Transplant Patients - Biogen PubMed (https://investors.biogen.com/news-releases/news-release-details/biogen-initiates-phase-3-study-felzartamab-treatment-late) 6. [6] TRANSCEND: A Phase 3 Trial of the Anti-CD38 Antibody Felzartamab in Kidney Transplant Recipients with Late Antibody-Mediated Rejection - American Journal of Transplantation PubMed (https://www.amjtransplant.org/article/S1600-6135(25)02024-6/fulltext) 7. [7] PREVAIL: A Phase 3 Study of Felzartamab in IgA Nephropathy (NCT06935357) - ClinicalTrials.gov PubMed (https://clinicaltrials.gov/study/NCT06935357) ### Keep researching in the app - Log Felzartamab to your private tracker - Set a dosing reminder - Compare it side-by-side with your stack Open PepTracker Pro Free: https://app.peptrackerpro.com/?add=felzartamab Browse more peptides: https://peptrackerpro.com/peptides ## Related Peptides ### Batoclimab High Evidence Batoclimab (development codes IMVT-1401, RVT-1401, HBM9161, HL161) is an investigational, fully human IgG1 monoclonal antibody that blocks the neonatal Fc receptor (FcRn), developed by Immunovant/Roivant (U.S. and Canada) and Harbour BioMed (Greater China) under license from HanAll Biopharma. It is not a small synthetic peptide but a full-length antibody given as a low-volume subcutaneous injection that patients can self-administer at home. Like the approved FcRn blockers efgartigimod, nipocalimab and rozanolixizumab, it lowers circulating IgG - including pathogenic autoantibodies - but it is best known for two things the others are not: it is the FcRn blocker that generated positive Phase 3 myasthenia gravis data yet was deliberately NOT filed for U.S. approval, and it is the one whose FcRn-mediated albumin recycling blockade produces a distinctive on-target signal of lowered serum albumin and raised LDL cholesterol - the exact liability that drove its makers to a re-engineered successor, IMVT-1402. Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation Neuromuscular Function: https://peptrackerpro.com/benefits/neuromuscular-function Rare Disease Treatment: https://peptrackerpro.com/benefits/rare-disease-treatment Disease Modification: https://peptrackerpro.com/benefits/disease-modification View Details: https://peptrackerpro.com/peptides/batoclimab \+ Compare: https://peptrackerpro.com/compare?select=batoclimab Track in App: https://app.peptrackerpro.com/?add=batoclimab ### Efgartigimod High Evidence Efgartigimod (efgartigimod alfa, brand names Vyvgart intravenous and Vyvgart Hytrulo subcutaneous) is a first-in-class antagonist of the neonatal Fc receptor (FcRn) developed by argenx as ARGX-113. It is not a small synthetic peptide but an engineered fragment of the human immunoglobulin G1 (IgG1) antibody - specifically the Fc portion that normally binds FcRn - modified with argenx's ABDEG technology to bind FcRn with much higher affinity than natural IgG at both neutral and acidic pH. FcRn is the salvage receptor that rescues circulating IgG from lysosomal degradation and recycles it back into the blood, giving antibodies their long half-life. By outcompeting endogenous IgG for FcRn, efgartigimod blocks that recycling and drives rapid clearance of IgG - including the pathogenic autoantibodies that cause many autoimmune diseases - typically lowering total IgG by roughly 60-70% within weeks, without reducing IgM, IgA, or albumin. It was the first FcRn blocker ever approved: FDA-approved in December 2021 (Vyvgart IV) for acetylcholine-receptor-antibody-positive generalized myasthenia gravis (gMG) on the strength of the Phase 3 ADAPT trial, followed by a subcutaneous co-formulation with recombinant hyaluronidase (Vyvgart Hytrulo) for gMG in 2023 and for chronic inflammatory demyelinating polyneuropathy (CIDP) in 2024. In May 2026 the FDA expanded the gMG label to all serotypes - including AChR-antibody-negative (seronegative) patients - based on the Phase 3 ADAPT SERON trial, making efgartigimod the first and only therapy approved across every gMG antibody subtype. It is being studied in a broad set of other IgG-driven autoimmune diseases, including primary immune thrombocytopenia, myositis, Sjogren's disease, bullous pemphigoid, and lupus nephritis. View Details: https://peptrackerpro.com/peptides/efgartigimod \+ Compare: https://peptrackerpro.com/compare?select=efgartigimod Track in App: https://app.peptrackerpro.com/?add=efgartigimod ### Nipocalimab High Evidence Nipocalimab (brand name Imaavy, development code M281) is a fully human, aglycosylated, 'effectorless' IgG1 monoclonal antibody that blocks the neonatal Fc receptor (FcRn), developed by Johnson & Johnson (Janssen). Like efgartigimod it lowers circulating immunoglobulin G (IgG) - including the pathogenic autoantibodies that drive many autoimmune diseases - by occupying FcRn and preventing it from recycling IgG back into the blood, so unrescued IgG is routed to the lysosome and degraded, typically cutting total IgG by roughly 65-75% while sparing IgM, IgA, complement, and albumin. Unlike efgartigimod's engineered Fc fragment, nipocalimab is a full-length monoclonal antibody engineered to be aglycosylated and effectorless (it does not trigger ADCC or complement-dependent cytotoxicity), and it is dosed as a maintenance intravenous infusion for continuous IgG suppression rather than in short cycles. The FDA approved Imaavy on April 30, 2025 for generalized myasthenia gravis (gMG) in anti-AChR-antibody-positive and anti-MuSK-antibody-positive patients aged 12 and older - making it the first FcRn blocker approved for adolescents and the first to explicitly cover MuSK-positive disease - on the strength of the Phase 3 Vivacity-MG3 trial. It has since generated positive data across a striking breadth of IgG-mediated conditions: Sjogren's disease (Phase 2 DAHLIAS), rheumatoid arthritis, warm autoimmune hemolytic anemia (wAIHA), and - uniquely among FcRn blockers - maternal-fetal alloimmune disease, where it is being developed to treat hemolytic disease of the fetus and newborn (HDFN) by crossing the placenta to protect the fetus. In April 2026 the FDA granted Priority Review to nipocalimab for wAIHA, positioning it as a potential first approved therapy for that condition. View Details: https://peptrackerpro.com/peptides/nipocalimab \+ Compare: https://peptrackerpro.com/compare?select=nipocalimab Track in App: https://app.peptrackerpro.com/?add=nipocalimab ### Rozanolixizumab High Evidence Rozanolixizumab (brand name Rystiggo, development code UCB7665) is a humanized IgG4 monoclonal antibody that blocks the neonatal Fc receptor (FcRn), developed by UCB. Like efgartigimod and nipocalimab it lowers circulating immunoglobulin G (IgG) - including the pathogenic autoantibodies that drive many autoimmune diseases - by binding FcRn and preventing it from recycling IgG back into the blood, so unrescued IgG is routed to the lysosome and degraded, typically cutting total IgG by roughly 70-80% while sparing IgM, IgA, complement, and albumin. Unlike efgartigimod's engineered Fc fragment, rozanolixizumab is a full-length humanized antibody, and unlike nipocalimab's intravenous infusion it is given as a rapid subcutaneous infusion (including via an on-body delivery device), typically in weekly cycles that are repeated based on clinical response rather than continuously. The FDA approved Rystiggo on June 27, 2023 for generalized myasthenia gravis (gMG) in adults who are anti-acetylcholine-receptor (AChR) antibody-positive or anti-muscle-specific-tyrosine-kinase (MuSK) antibody-positive - making it the first therapy ever approved to treat both of those gMG subtypes - on the strength of the Phase 3 MycarinG trial. It has since been studied across other IgG-mediated diseases, including chronic inflammatory demyelinating polyneuropathy (CIDP), where it did not show meaningful benefit and was not advanced to Phase 3, and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), primary immune thrombocytopenia (ITP), and other autoantibody conditions where development continues. The European Medicines Agency approved rozanolixizumab in January 2024 and the UK MHRA in March 2024. View Details: https://peptrackerpro.com/peptides/rozanolixizumab \+ Compare: https://peptrackerpro.com/compare?select=rozanolixizumab Track in App: https://app.peptrackerpro.com/?add=rozanolixizumab ### Povetacicept High Evidence Povetacicept (development code ALPN-303) is an investigational, once-monthly, subcutaneously injected recombinant fusion protein that simultaneously blocks two B-cell survival signals - BAFF (B-cell activating factor) and APRIL (a proliferation-inducing ligand). It is built from an engineered ('variant') form of the natural TACI receptor's extracellular domain fused to an antibody (IgG) Fc region, so it acts as a high-affinity decoy that soaks up both BAFF and APRIL before they can reach their receptors on B cells and plasma cells. Because BAFF and APRIL drive the maturation and antibody production of the immune cells behind many autoantibody- and immune-complex-mediated diseases, povetacicept is being developed for B-cell-driven autoimmune conditions - most prominently IgA nephropathy (IgAN), where APRIL fuels the production of the galactose-deficient IgA1 that damages the kidney. Originated by Alpine Immune Sciences (acquired by Vertex Pharmaceuticals in 2024), povetacicept has received FDA Breakthrough Therapy Designation for IgAN; in March 2026 the Phase 3 RAINIER trial reported a positive prespecified Week 36 interim analysis (a ~52% reduction in urine protein-to-creatinine ratio from baseline and a ~50% reduction versus placebo), and in June 2026 the FDA accepted a Biologics License Application for accelerated approval with a target action date of November 30, 2026. Povetacicept is an experimental biologic given only in clinical trials; it is not a supplement, nootropic, or research chemical. View Details: https://peptrackerpro.com/peptides/povetacicept \+ Compare: https://peptrackerpro.com/compare?select=povetacicept Track in App: https://app.peptrackerpro.com/?add=povetacicept ### Sibeprenlimab High Evidence Sibeprenlimab (brand name VOYXACT; nonproprietary name sibeprenlimab-szsi; development code VIS649) is a humanized monoclonal antibody that binds and neutralizes APRIL (a proliferation-inducing ligand), a cytokine that drives the abnormal, antibody-producing B cells behind IgA nephropathy. By soaking up circulating APRIL with very high affinity, it lowers production of galactose-deficient IgA1 (Gd-IgA1) - the mis-glycosylated antibody whose immune complexes deposit in the kidney and cause the proteinuria and progressive damage of IgA nephropathy (IgAN). Given as a fixed 400 mg subcutaneous injection once every 4 weeks from a single-dose prefilled syringe, sibeprenlimab is designed for at-home self-administration. Originated by Visterra (acquired by Otsuka Pharmaceutical in 2018), it advanced through the Phase 2 ENVISION trial and the pivotal Phase 3 VISIONARY trial - the largest Phase 3 study conducted in IgAN - where it produced a roughly 50-54% placebo-adjusted reduction in proteinuria and signs of preserved kidney function (eGFR). On the strength of those data and an FDA Breakthrough Therapy Designation, the U.S. FDA granted VOYXACT accelerated approval in November 2025 to reduce proteinuria in adults with primary IgAN at risk of disease progression, and Otsuka began a rolling supplemental filing in 2026 seeking traditional approval on longer-term kidney-function data. Sibeprenlimab is a prescription biologic administered under medical care; it is not a supplement, nootropic, or research chemical. View Details: https://peptrackerpro.com/peptides/sibeprenlimab \+ Compare: https://peptrackerpro.com/compare?select=sibeprenlimab Track in App: https://app.peptrackerpro.com/?add=sibeprenlimab ### Atacicept High Evidence Atacicept (brand name Trutakna) is a recombinant soluble TACI-Fc fusion protein and the first dual BAFF/APRIL inhibitor approved for IgA nephropathy (IgAN). It fuses the extracellular ligand-binding domain of the TACI receptor to the Fc region of human IgG1, letting it soak up two B-cell survival cytokines at once - BAFF (B-cell activating factor) and APRIL (a proliferation-inducing ligand). By starving autoreactive B cells and plasma cells of both signals, atacicept lowers production of galactose-deficient IgA1 (Gd-IgA1), the abnormal antibody that drives immune-complex deposition and kidney injury in IgAN. It is given as a 150 mg once-weekly subcutaneous self-injection with an autoinjector at home. On July 7, 2026 the FDA granted atacicept accelerated approval (as Trutakna) to reduce proteinuria in adults with primary IgAN at risk of progression - the first and only BAFF-and-APRIL inhibitor cleared for the disease - based on the Phase 3 ORIGIN 3 trial (NCT04716231, 431 adults), in which it cut urine protein (UPCR) 46% from baseline and 42% versus placebo at week 36 (p<0.0001), reduced Gd-IgA1 by 68%, resolved hematuria in 81% of those with baseline blood in the urine, and produced serious adverse events in only 0.5% of patients (versus 5% on placebo). Originated at ZymoGenetics and developed by Merck KGaA (Merck Serono) before being out-licensed to Vera Therapeutics, atacicept sits alongside the anti-APRIL antibody sibeprenlimab and the engineered dual BAFF/APRIL inhibitor povetacicept in the fast-moving IgAN pipeline. View Details: https://peptrackerpro.com/peptides/atacicept \+ Compare: https://peptrackerpro.com/compare?select=atacicept Track in App: https://app.peptrackerpro.com/?add=atacicept ## Structured data ```json [ { "@context": "https://schema.org", "@type": "Organization", "name": "PepTracker Pro", "url": "https://peptrackerpro.com", "logo": "https://peptrackerpro.com/favicon.png", "description": "Evidence-based educational resource dedicated to improving peptide research literacy.", "contactPoint": { "@type": "ContactPoint", "email": "hello@peptrackerpro.com", "contactType": "customer support" }, "sameAs": [] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "Felzartamab", "description": "Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical.", "url": "https://peptrackerpro.com/peptides/felzartamab", "lastReviewed": "2026-09-19", "reviewedBy": { "@type": "Organization", "name": "PepTracker Pro Research Team", "url": "https://peptrackerpro.com" }, "isPartOf": { "@type": "WebSite", "name": "PepTracker Pro", "url": "https://peptrackerpro.com" } }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://peptrackerpro.com" }, { "@type": "ListItem", "position": 2, "name": "Peptides", "item": "https://peptrackerpro.com/peptides" }, { "@type": "ListItem", "position": 3, "name": "Felzartamab", "item": "https://peptrackerpro.com/peptides/felzartamab" } ] }, { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "Patients and nephrologists following new plasma-cell-depleting or antibody-directed treatments for IgA nephropathy, primary membranous nephropathy and other autoantibody-driven glomerular diseases?", "acceptedAnswer": { "@type": "Answer", "text": "Felzartamab is a research peptide studied in preclinical models. Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." } }, { "@type": "Question", "name": "Kidney transplant patients and transplant nephrologists interested in late antibody-mediated rejection (AMR), a setting with essentially no approved therapy, where felzartamab has shown early promise?", "acceptedAnswer": { "@type": "Answer", "text": "Felzartamab is a research peptide studied in preclinical models. Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." } }, { "@type": "Question", "name": "Clinicians and researchers comparing mechanisms across the new wave of immunology biologics - CD38/plasma-cell depletion (felzartamab) versus APRIL/BAFF blockade (sibeprenlimab, povetacicept) versus FcRn inhibition (efgartigimod, nipocalimab, rozanolixizumab, batoclimab)?", "acceptedAnswer": { "@type": "Answer", "text": "Felzartamab is a research peptide studied in preclinical models. Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." } }, { "@type": "Question", "name": "Industry watchers and investors tracking Biogen's immunology and rare-kidney-disease pipeline following its 2024 acquisition of HI-Bio and 2026 consolidation of the Greater China rights from TJ Biopharma?", "acceptedAnswer": { "@type": "Answer", "text": "Felzartamab is a research peptide studied in preclinical models. Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." } }, { "@type": "Question", "name": "Readers who encounter 'felzartamab', 'MOR202' or 'TJ202' online and want to understand what it is, how it differs from myeloma CD38 antibodies like daratumumab, and why it is being tested in kidney disease?", "acceptedAnswer": { "@type": "Answer", "text": "Felzartamab is a research peptide studied in preclinical models. Felzartamab (development codes MOR202/MOR03087, and TJ202 in Greater China) is an investigational fully human IgG1 monoclonal antibody that targets CD38, a protein carried at high density on the antibody-producing plasma cells and plasmablasts of the immune system. Rather than blocking a single circulating antibody or downstream mediator, felzartamab depletes the very cells that manufacture pathogenic (disease-causing) antibodies, with the logic that shutting down the factory stops the harmful antibodies at their source. CD38 antibodies are an established drug class in cancer (daratumumab and isatuximab are approved for multiple myeloma), and felzartamab is being repurposed to switch off the autoantibody-driven immune attack behind several serious kidney diseases. It is given as an intravenous infusion in defined treatment courses (for example, a roughly five- to nine-dose regimen) rather than indefinitely. Felzartamab has become one of the most closely watched agents in nephrology because it is advancing through three separate Phase 3 programs in rare, antibody-mediated kidney diseases: IgA nephropathy (IgAN), primary membranous nephropathy (PMN), and late antibody-mediated rejection (AMR) of a transplanted kidney. It originated at MorphoSys AG, was licensed to Human Immunology Biosciences (HI-Bio), which Biogen acquired in 2024, and Biogen consolidated the Greater China rights from TJ Biopharma in 2026. It holds FDA Breakthrough Therapy designation in primary membranous nephropathy. Felzartamab is an investigational prescription biologic administered under medical supervision; it is not approved for kidney disease, and it is not a supplement, nootropic or research chemical." } } ] } ] ```