Recruiting
Phase 3

Felzartamab vs. Tacrolimus

Sponsor:

Biogen

Code:

NCT06962800

Conditions

Primary Membranous Nephropathy

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Interventions

Felzartamab

Tacrolimus

Standard of Care IST

Study Details

Brief summary:

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:

  • How many participants achieve a complete response after 104 weeks of treatment?
  • A complete response means that their urine protein levels decrease to a low level and their kidney function remains stable.

Researchers will also learn about:

  • How long it takes before the participants' disease gets worse
  • How long the participants' urine protein levels stay low
  • How many participants develop antibodies against felzartamab in the blood?
  • How many participants achieve a complete response after 76 weeks of treatment
  • How many participants have medical problems during the study
  • How felzartamab is processed by the body
  • How felzartamab affects participants' tiredness and overall physical health

The study will be done as follows:

  • Participants will be screened to check if they can join the study. This may take up to 42 days.
  • Participants will be randomized to receive either felzartamab as intravenous (IV) infusions or tacrolimus, taken orally as tablets.
  • If participants have worsening kidney function or worsening proteinuria, or if their PMN relapses, or if they show no signs of improvement in their PMN, they will have a chance to receive rescue treatment.
  • If a participant stops treatment early, there will be follow-up visits every 12 weeks until they reach Week 104.
  • In total, participants will have up to 23 study visits. Participants who do not need rescue treatment will stay in the study for up to 104 weeks. Participants who need rescue treatment will stay in the study for up to 156 weeks.

Conditions

Primary Membranous Nephropathy

Study ID

NCT06962800

Start date

May 22, 2025

Status verified date

Aug, 2026

Completion date

Jan 17, 2031

Anticipated

Primary completion date

Jan 28, 2030

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

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:

1. Newly diagnosed PMN, defined as having never received IST for PMN in the past.
2. Relapsed PMN, defined as documented achievement of CR or partial remission (PR) after treatment with an IST for PMN followed by reappearance of nephrotic range proteinuria (urine protein to creatinine ratio \[UPCR\] ≥ 3.0 gram per gram \[g/g\] from a 24-hour urine collection or proteinuria ≥ 3.5 gram per 24 hour \[g/24 h\]).
  • Participants must be on the maximally approved dose or maximally tolerated dose of at least one renin-angiotensin-aldosterone system (RAAS) inhibition therapy (e.g. angiotensin-converting enzyme inhibitor \[ACEI\], angiotensin receptor blocker \[ARB\], and/or mineralocorticoid receptor antagonists \[MRA\]) for at least 4 weeks prior to Screening. Participants not on the maximally approved dose of RAAS inhibition may be enrolled provided there is documented intolerance to maximal RAAS inhibition (e.g., angioedema, development of postural hypotension, lightheadedness, hyperkalemia, etc). Participants on MRA therapy alone at Screening must have documented prior intolerance of ACEI or ARB therapy. Participants who do not tolerate ACEI or ARB therapy are not required to start MRA therapy prior to Screening.
  • A UPCR of ≥ 3.0 g/g (as determined by a 24-hour urine collection) or total proteinuria ≥ 3.5 g/24 h (as determined by a 24-hour urine collection) at Screening after best supportive care for at least 4 weeks prior to signing the ICF.

Key Exclusion Criteria:

  • Secondary cause of MN (e.g., malignancies, medications, systemic lupus erythematosus \[SLE\], hepatitis B, hepatitis C, etc).
  • Severe renal impairment is defined as an eGFR ≤ 30 mL/min/1.73m\^2 at Screening or including the need for dialysis or renal replacement therapy.

Note: Other protocol-defined Inclusion/Exclusion criteria may apply.

Study Design

Enrollment

180 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Open-Label Treatment Phase

Participants will receive several intravenous (IV) doses of felzartamab or oral tacrolimus in the Open-Label Treatment Phase.

experimental: Non-Responder Treatment Phase

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.

Interventions

Felzartamab

Administered intravenously

Tacrolimus

Administered orally

Standard of Care IST

Administered intravenously and orally

Primary outcome measure

  • Percentage of Participants who Achieve Complete Remission (CR) at Week 104 [ Time Frame: Week 104 ]

Central Contacts and Locations

Central contacts

US Biogen Clinical Trial Center

866-633-4636clinicaltrials@biogen.com

Global Biogen Clinical Trial Center

clinicaltrials@biogen.com

Locations

Apogee Clinical Research, LLC

Recruiting

Huntsville, Alabama, United States, 35805-4104

Contacts

256-533-4626

Principal Investigator:

Michael Quadrini

The Nephrology Group, Inc. - Fresno

Recruiting

Fresno, California, United States, 93720-2989

Contacts

559-228-6600

Principal Investigator:

Yangming Cao

Academic Medical Research Institute

Recruiting

Los Angeles, California, United States, 90022

Contacts

323-725-0051

Principal Investigator:

Mohamed El-Shahawy

UCLA Health Connie Frank Kidney Transplant Center and General Nephrology

Recruiting

Los Angeles, California, United States, 90095-8344

Contacts

310-794-5024

Principal Investigator:

Anjay Rastogi

UCSF Medical Center

Recruiting

San Francisco, California, United States, 94143-2205

Contacts

415-353-7900

Principal Investigator:

Christopher Carlos

Stanford University

Recruiting

Stanford, California, United States, 94305-2200

Contacts

650-721-4011

Principal Investigator:

Fahmeedah Kamal

Henry Ford Hospital- A-Basement Research Pharmacy

Recruiting

Detroit, Michigan, United States, 48202-2608

Contacts

313-900-2298

Principal Investigator:

Douglas Atchison

James J Peters Veterans Administration Medical Center - NAVREF - PPDS

Recruiting

The Bronx, New York, United States, 10468

Contacts

718-584-9000

Principal Investigator:

Chang Xu

ECU Physicians Nephrology and Hypertension

Recruiting

Greenville, North Carolina, United States, 27834

Contacts

252-744-2545obir@ecu.edu

Principal Investigator:

Reginald Obi

University Hospitals Cleveland Medical Center

Recruiting

Cleveland, Ohio, United States, 44106-1716

Contacts

440-951-3500andrew.lazar@uhhospitals.com

Principal Investigator:

Lazar, Andrew

Knoxville Kidney Center, PLLC

Recruiting

Knoxville, Tennessee, United States, 37923-3624

Contacts

865-692-3462

Principal Investigator:

George Newman

Vanderbilt University Medical Center

Recruiting

Nashville, Tennessee, United States, 37204-3609

Contacts

615-936-1179

Principal Investigator:

Neil Sanghani

Nephrotex Research Group

Recruiting

Dallas, Texas, United States, 75231-0929

Contacts

214-396-4950

Principal Investigator:

Sumit Kumar

University of Texas Medical Branch

Recruiting

League City, Texas, United States, 77573

Contacts

409-772-2473

Principal Investigator:

Shikha Wadhwani

University of Wisconsin School of Medicine and Public Health

Recruiting

Madison, Wisconsin, United States, 53792-0001

Contacts

608-265-0631

Principal Investigator:

Sarah Panzer

Vancouver Coastal Health Research Institute

Recruiting

Vancouver, British Columbia, Canada, V5Z 1M9

Contacts

6048754323

Principal Investigator:

Sean Barbour

London Health Sciences Centre - Victoria Hospital

Recruiting

London, Ontario, Canada, N6A 5W9

Contacts

5196858066susan.huang@lhsc.on.ca

Principal Investigator:

Huang, Susan (Shih-Han)

More Information

Sponsor

Biogen

Last update posted

Aug 26, 2026

Last verified

Aug, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Biogen on 2026-08-26.