A Phase 3 interventional study of Felzartamab and Tacrolimus in Primary Membranous Nephropathy, sponsored by Biogen. Recruiting at 114 sites in 11 countries. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-29.
Sponsored by Biogen · Phase 3, Interventional, and Treatment
In this study, researchers will learn more about the use of felzartamab in participants with primary membranous nephropathy, also known as PMN. In people with PMN, autoantibodies build up in the glomeruli of the kidney. Antibodies are proteins that help the body fight off infection. An autoantibody is a type of antibody that mistakenly targets and attacks the body's own tissues. Glomeruli are the filters of the kidney that remove waste and extra fluid from the body. In PMN, the build-up of autoantibodies in the glomeruli causes damage to the kidneys.
Kidney damage can lead to too much protein and blood leaking into the urine. High levels of protein in the urine, called proteinuria, are common in people with PMN. Symptoms of PMN can include swelling in the legs and body, tiredness, and high blood pressure. If left untreated, PMN can eventually lead to kidney failure.
In this study, researchers will learn more about how a study drug called felzartamab affects people with PMN. Felzartamab is a monoclonal antibody, which means it is an antibody made in a laboratory. Felzartamab can target immune cells that produce autoantibodies, helping to lower their buildup in the kidneys. The main goal of this study is to compare how felzartamab works compared to a drug called tacrolimus. Tacrolimus is another drug given to people with PMN and kidney disease.
The main question that researchers want to answer is:
Researchers will also learn about:
The study will be done as follows:
The primary objective of the study is to assess the efficacy of felzartamab compared to tacrolimus in participants with PMN in achieving complete remission (CR) of proteinuria. The secondary objectives of the study are to evaluate the efficacy of felzartamab through additional clinical endpoints and timepoints, to assess the impact of felzartamab on serum anti-phospholipase A2 receptor (PLA2R) antibodies and patient-reported outcomes, and to assess the safety, pharmacokinetics (PK) and immunogenicity of felzartamab.
Biogen is the lead sponsor of 494 studies on the registry; 22 are open to participants now.
Of its 98 completed or terminated interventional studies of FDA-regulated products, 49 (50%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Diagnosed with PMN in need of IST according to the Investigator's clinical judgment. The diagnosis of PMN must be documented with the presence of nephrotic syndrome, and hypoalbuminemia, and confirmed with a kidney biopsy either during Screening or within 5 years of signing the informed consent form (ICF) [see kidney biopsy exception below for participants positive for anti-PLA2R antibodies]. For these participants, the biopsy report with redacted protected health information must be available to be reviewed by the Sponsor or an independent nephropathologist. If the participant requires a kidney biopsy during Screening, medical monitor approval must be obtained, and all other eligibility criteria should be reviewed to ensure that the participant is otherwise eligible prior to performing the kidney biopsy.
a. Kidney biopsy exception for anti-PLA2R antibody positive participants: Participants who are positive for anti-PLA2R antibodies at Screening and have not had a kidney biopsy performed within 5 years of signing the ICF may be eligible for the study without undergoing a kidney biopsy based on medical monitor review of screening tests confirming normal estimated glomerular filtration rate (eGFR), presence of nephrotic syndrome, hypoalbuminemia, positive anti-PLA2R antibody test (defined as an anti-PLA2R antibody titer ≥ 20 RU/mL), and documentation provided by the Investigator that the work-up for secondary causes of membranous nephropathy (MN) was negative with no identifiable secondary causes.
Meets one of the following:
Key Exclusion Criteria:
Note: Other protocol-defined Inclusion/Exclusion criteria may apply.
Participants will receive several intravenous (IV) doses of felzartamab or oral tacrolimus in the Open-Label Treatment Phase.
Drug: Felzartamab · Drug: Tacrolimus
Participants initially randomized to felzartamab or tacrolimus who meet rescue criteria may receive regional standard of care immunosuppressive therapy (IST) per Investigator discretion or several IV doses of felzartamab, respectively, in the Non-Responder Treatment Phase.
Drug: Felzartamab · Drug: Standard of Care IST
Administered intravenously
Also known as: MOR202, MOR03087, TJ202, BIIB148, HIB202
Administered orally
Administered intravenously and orally
Percentage of Participants who Achieve Complete Remission (CR) at Week 104
Time frame: Week 104
Percentage of Participants who Achieve Overall Remission (OR), Defined as CR or Partial Remission (PR) at Week 104
Time frame: Week 104
Percentage of Participants who Achieve CR at Week 76
Time frame: Week 76
Duration of CR
Time frame: Baseline up to Week 156
Percentage of Participants With a Baseline Anti-Phospholipase A2 Receptor (PLA2R) Autoantibody Titer Greater Than 50 Relative Unit per Milliliter (RU/mL) who Achieve an OR at Week 76 and at Week 104
Time frame: Weeks 76 and 104
Time to Disease Worsening
Time frame: Baseline up to Week 156
Time to a Sustained Reduction in eGFR of ≥ 30% From Baseline
Time frame: Baseline up to Week 104
Absolute Change in Anti-PLA2R Autoantibody Titer in Participants Positive for Anti-PLA2R at Baseline
Time frame: Baseline up to Week 156
Change From Baseline in the Patient Reported Outcome Measurement Information System (PROMIS) Fatigue Scale at Week 104
Time frame: Week 104
Change From Baseline in PROMIS Global Assessment of Physical Health Scale at Week 104
Time frame: Week 104
Number of Participants With Treatment Emergent Adverse Event (TEAE), Serious Adverse Event (SAE) and Adverse Events of Special Interest (AESIs)
Time frame: From first dose of study drug up to end of follow-up (up to Week 156)
Felzartamab Serum Concentrations Over Time
Time frame: Predose and at multiple timepoints post dose up to Week 156
Number of Participants With Anti-Drug Antibodies (ADAs) Against Felzartamab
Time frame: Predose and at multiple timepoints post dose up to Week 156
Showing the first 100 of 114 sites across 11 countries.
Plan to share: Yes — In accordance with Biogen's Clinical Trial Transparency and Data Sharing Policy on https://www.biogentrialtransparency.com/
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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