Recruiting
Phase 3

Felzartamab

Sponsor:

Biogen

Code:

NCT06935357

Conditions

Immunoglobulin A Nephropathy (IgAN)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Felzartamab

Placebo

Study Details

Brief summary:

In this study, researchers will learn more about the use of felzartamab in participants with immunoglobulin A nephropathy (IgAN). IgAN is a kidney disease caused by the buildup of an antibody called IgA in the kidneys over time. In people with IgAN, abnormal IgA and other antibodies form clusters that build up in the small filters of the kidneys, which leads to inflammation and damage. Felzartamab is designed to target certain immune cells that produce these abnormal antibodies. This study will focus on participants who have protein in their urine (proteinuria) as a result of damaged kidneys.

The main goal of the study is to learn about the effect felzartamab has on proteinuria. The main question that researchers want to answer is:

• How much does the amount of protein in the urine change from the start of the study to Week 36?

Researchers will learn about the effect felzartamab has on the kidneys' ability to filter blood. They will also learn more about the safety of felzartamab and how it is processed by the body.

The study will be done as follows:

  • Participants will be screened to check if they can join the study.
  • Participants will be randomized to receive either felzartamab or a placebo. A placebo looks like the study drug but contains no real medicine.
  • Neither the researchers nor the participants will know what the participants will receive.
  • Participants will receive felzartamab or placebo as intravenous (IV) infusions. The treatment period will last 24 weeks.
  • Afterwards, participants will enter a follow-up period which will last 80 weeks.
  • In total, participants will have 17 study visits. Participants will stay in the study for about 2 years.

Conditions

Immunoglobulin A Nephropathy (IgAN)

Study ID

NCT06935357

Start date

May 8, 2025

Status verified date

Sep, 2026

Completion date

Jun 5, 2029

Anticipated

Primary completion date

May 31, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Key Inclusion Criteria:

  • Biopsy-confirmed diagnosis of IgAN within the past 10 years prior to signature of the informed consent form (ICF). For participants with diabetes mellitus type 2, an IgAN diagnostic biopsy within the past 24 months prior to signing the ICF.
  • An eGFR ≥ 30 mL/min/1.73 m\^2 at Screening as calculated using the 2021 chronic kidney disease epidemiology (CKD-EPI) creatinine formula. An eGFR of ≥ 20 and < 30 mL/min/1.73 m\^2 is acceptable for the cohorts 3 and 4.
  • Proteinuria of ≥ 1.0 gram per day (g/day) or UPCR ≥0.8 gram per gram (g/g) as assessed by an adequate 24-hour urine collection.
  • Clinically stable on a maximally tolerated dose or maximally approved dose of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) for at least 12 weeks prior to Screening. Participants may also be using sodium-glucose cotransporter-2 inhibitors (SGLT2is); endothelin receptor antagonists (ERAs) or dual endothelin angiotensin receptor antagonist (DEARAs) approved for the treatment of IgAN; and/or mineralocorticoid receptor antagonists (MRAs) as long as the dose is stable for at least 12 weeks prior to Screening. Participants should remain on stable doses of these background medications for the duration of the study. Once the ICF is signed and thereafter, the doses cannot be changed during the study nor the drugs discontinued except if deemed related to an AE. Participants using a DEARA (e.g., sparsentan) will not be permitted to use simultaneous ACEI or ARB medication.

Key Exclusion Criteria:

  • Any history of secondary forms of IgAN, indicated by the presence of any other systemic disease potentially leading to IgA deposits as determined by the Investigator.
  • History of rapidly progressive variant of IgAN, defined as eGFR loss by > 50% per 3 months and not explained by changes in renin-angiotensin system (RAS) blockade or other factors.
  • IgAN-(MCD) variant.
  • Concomitant other progressive glomerulonephritis or non-immunologic glomerular disease such as diabetic nephropathy.
  • Type 2 diabetes mellitus with Hemoglobin A1c (HbA1c) > 8% at Screening, or evidence of diabetic nephropathy on biopsy, history of diabetic microvascular or macrovascular disease (eg, diabetic retinopathy, peripheral neuropathy).
  • Any diagnosed or suspected immunosuppressed or immunodeficient state such as asplenia, human immunodeficiency virus (HIV), primary immunodeficiencies, organ or bone marrow transplantation, with the exception of corneal transplants.
  • Previously treated with immunosuppressive or other immunomodulatory agents such as but not limited to cyclophosphamide, rituximab, infliximab, eculizumab, canakinumab, mycophenolate mofetil (MMF) or mycophenolate sodium (MPS), cyclosporine, tacrolimus, sirolimus, everolimus, or systemic glucocorticoid exposure (> 7.5 milligrams per day \[mg/d\] prednisone-equivalent for indications other than IgAN or any dose if given for the treatment of IgAN) within 4 months prior to Screening. Use of hydroxychloroquine in Mainland China is allowed if the candidate has been on this for at least 6 months prior to Screening with a stable dose for at least 12 weeks prior to Screening. If a potential participant requires systemic glucocorticoids at any dose for IgAN during Screening, this will result in a screen fail. If a potential participant requires systemic glucocorticoids > 7.5 mg/day prednisone-equivalent for indications other than IgAN during Screening, this will result in a screen fail.
  • Participants currently treated with oral budesonide. Participants who have stopped this therapy ≥ 4 months prior to Screening may be eligible.
  • Active clinically significant infections, known history of recurrent clinically significant infection, or Screening laboratory evidence consistent with an active infection, or non-prophylactic treatment with IV anti-infectives (antibacterials, antiviral or antifungals). Participants with a history of opportunistic infections are excluded.
  • Hypogammaglobulinemia: serum Immunoglobin G (IgG) < 6.0 gram per litre (g/L), at Screening.

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

Study Design

Enrollment

454 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Cohort 1

Participants will receive several intravenous (IV) doses of felzartamab.

placebo comparator: Cohort 2

Participants will receive several IV doses of placebo.

experimental: Cohort 3

Participants with an estimated glomerular filtration rate (eGFR) ≥ 20 and <30 milliliter per minute per 1.73 square meter (mL/min/1.73m\^2) will receive several IV doses of felzartamab.

placebo comparator: Cohort 4

Participants with an eGFR ≥ 20 and <30 mL/min/1.73m\^2 will receive several IV doses of placebo.

Interventions

Felzartamab

Administered IV

Placebo

Administered IV

Primary outcome measure

  • Percent Change From Baseline in Proteinuria as Measured by the Urine Protein: Creatinine Ratio (UPCR) [ Time Frame: Baseline up to Week 36 ]

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

Applied Research Center of Arkansas

Recruiting

Little Rock, Arkansas, United States, 72205

Contacts

501-804-5939

Principal Investigator:

John Heifner

Kidney & Hypertension Center - Apple Valley

Recruiting

Apple Valley, California, United States, 92307

Contacts

760-780-4179

Principal Investigator:

Edgard Vera Tapia

Scripps Green Hospital

Recruiting

Carlsbad, California, United States, 92009

Contacts

617-956-2587

Principal Investigator:

Kimberly Harper

UCLA Health David Geffen School of Medicine

Recruiting

Los Angeles, California, United States, 90095

Contacts

310-206-8478

Principal Investigator:

Anjay Rastogi

FOMAT Medical Research - FOMAT - PPDS

Recruiting

Oxnard, California, United States, 93030

Contacts

805-483-1185

Principal Investigator:

Koosha Mortazavi

North America Research Institute-San Dimas

Recruiting

San Dimas, California, United States, 91773

Contacts

800-797-1695

Principal Investigator:

Aamir Jamal

Nova Clinical Research, LLC

Recruiting

Bradenton, Florida, United States, 34209

Contacts

941-792-6564

Principal Investigator:

Hakan Toka

University of Florida - Gainesville - 1600 SW Archer Rd

Recruiting

Gainesville, Florida, United States, 32610

Contacts

352-294-5068

Principal Investigator:

Wai Lau

Royal Research, Corp.

Recruiting

Hollywood, Florida, United States, 33024

Contacts

954-940-0208

Principal Investigator:

Elio Torres

Central Florida Kidney Specialists

Recruiting

Orlando, Florida, United States, 32806

Contacts

407-472-5120

Principal Investigator:

Arvind Madan

CDC Research Institute, LLC

Recruiting

Port Saint Lucie, Florida, United States, 34952

Contacts

772-807-1636

Principal Investigator:

Pablo Puello Diaz

The Vasculitis and Glomerulonephritis Center at Massachusetts General Hospital

Recruiting

Boston, Massachusetts, United States, 02114-4724

Contacts

617-726-4132

Principal Investigator:

Harish Seethapathy

Brigham and Women's Hospital

Recruiting

Boston, Massachusetts, United States, 02115-6110

Contacts

617-732-8327

Principal Investigator:

Finnian McCausland

Henry Ford Hospital

Recruiting

Detroit, Michigan, United States, 48202

Contacts

313-916-0026

Principal Investigator:

Douglas Atchison

Anointed Nephrology and HTN - SKYCRNG - PPDS

Recruiting

Brookhaven, Mississippi, United States, 39601

Contacts

601-833-4111

Principal Investigator:

James Hall

James J Peters Veterans Administration Medical Center - NAVREF - PPDS

Recruiting

The Bronx, New York, United States, 10468

Contacts

71858490006099

Principal Investigator:

Chang Xu

Lifespan at Rhode Island Hospital

Recruiting

Providence, Rhode Island, United States, 02903

Contacts

401-444-6844

Principal Investigator:

Jie Tang

Knoxville Kidney Center, PLLC

Recruiting

Knoxville, Tennessee, United States, 37923-3624

Contacts

692-3462

Principal Investigator:

George Newman

Texas Kidney Institute - Dallas

Recruiting

Dallas, Texas, United States, 95231

Contacts

214-396-4950

Principal Investigator:

Sumit Kumar

Provecta Research Network

Recruiting

Houston, Texas, United States, 77054

Contacts

832-338-9118

Principal Investigator:

Biruh Workeneh

R & H Clinical Research

Recruiting

Katy, Texas, United States, 77974

Contacts

713-367-2791

Principal Investigator:

Syed Hussain

St Paul's Hospital

Recruiting

Vancouver, British Columbia, Canada, V6Z 1Y6

Contacts

6046822344

Principal Investigator:

Sean Barbour

McGill University Health Centre (MUHC)

Recruiting

Montreal, Quebec, Canada, H4A3J1

Contacts

5149341934

Principal Investigator:

Rita Suri

More Information

Sponsor

Biogen

Last update posted

Sep 2, 2026

Last verified

Sep, 2026

Keywords

  • Felzartamab

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Biogen on 2026-09-02.