A Study to Learn About the Effects of Felzartamab Infusions on Adults With Immunoglobulin A Nephropathy (IgAN) ( PREVAIL )

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Biogen Idec Research Limited

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Immune System Diseases [C20]

Trial duration

12 Nov 2025 → ongoing

Decision date (initial)

2025-09-23

Transition trial

No

Low-intervention

No

Rare-disease indication

Yes

Vulnerable population

Yes

Funding sources

Biogen Idec Research LTD

External identifiers

EU CT number

2024-519345-30-00

ClinicalTrials.gov

NCT06935357

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Efficacy, Pharmacokinetic

The primary objective of the study is to evaluate the efficacy of felzartamab compared to placebo on proteinuria in participants with Immunoglobulin A nephropathy (IgAN)

Secondary objectives 2

1. The main secondary objective of the study is to evaluate the efficacy of felzartamab compared to placebo on kidney functions in participants with IgAN.
2. The additional secondary objectives are to evaluate the efficacy of felzartamab compared to placebo on additional clinical endpoints and to assess the pharmacokinetics (PK) and immunogenicity of felzartamab.

Conditions and MedDRA coding

IgA nephropathy

Study design 1 period

Regulatory references

Scientific advice from competent authorities

European Medicines Agency

Plan to share IPD

Yes

IPD plan description

In accordance with Biogen's Clinical Trial Transparency and Data Sharing Policy on https://www.biogentrialtransparency.com/

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 4

1. 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, biopsy confirmation of IgAN diagnosis must be done within the past 24 months prior to signing the ICF.
2. An eGFR ≥ 30 mL/min/1.73m^2 at Screening as calculated using the 2021 chronic kidney disease epidemiology (CKD-EPI) creatinine formula. An eGFR of ≥ 20 and < 30 mL/min/1.73m^2 is acceptable for the cohorts 3 and 4.
3. 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, or intolerant of ACEI or ARB. If intolerant, this must be discussed with the Medical Monitor prior to randomization. Participants may also be using sodium-glucose cotransporter-2 inhibitors (SGLT2is), endothelin receptor antagonists (ERAs) approved for the treatment of IgAN, dual endothelin angiotensin receptor antagonists (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 sparsentan will not be permitted to use simultaneous ACEI or ARB medication.
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.

Exclusion criteria 11

1. Secondary forms of IgAN, indicated by the presence of any other systemic disease potentially leading to IgA deposits as determined by the Investigator.
2. Participants currently treated with oral budesonide. Patients who have stopped this therapy ≥ 4 months prior to Screening may be eligible.
3. Active clinically significant infections, known history of recurrent clinically significant infection, or Screening laboratory evidence consistent with an active infection, or IV anti- infectives (antibacterials, antivirals, or antifungals). Participants with a history of opportunistic infections are excluded.
4. History of rapidly progressive variant of IgAN, defined as eGFR loss by > 50% per 3 months and not explained by changes in RAS blockade or other factors.
5. Nephrotic syndrome presumed to be due to minimal change disease (MCD) variant
6. Concomitant other progressive glomerulonephritis or non-immunologic glomerular disease such as diabetic nephropathy.
7. 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).
8. 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.
9. Hypogammaglobulinemia: Serum Immunoglobin G (IgG) < 6.0 gram per litre (g/L), at Screening
10. Previously treated with immunosuppressive or other immunomodulatory agents such as but not limited to cyclophosphamide, rituximab, infliximab, eculizumab, canakinumab, MMF or mycophenolate sodium (MPS), cyclosporine, tacrolimus, sirolimus, everolimus, or systemic corticosteroids exposure (> 7.5 mg/d prednisone/prednisolone equivalent) within 4 months (or 12 months for rituximab) prior to Screening.
11. Note: Other protocol defined Inlcusion/Exclusion criteria may apply

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Percent Change From Baseline in Proteinuria as Measured by the Urine Protein: Creatinine Ratio (UPCR)

Secondary endpoints 12

1. Change From Baseline in Estimated Glomerular Filtration Rate (eGFR) Values Calculated Using the Chronic Kidney Disease Epidemiology (CKD-EPI) Creatinine Equation
2. Percentage of participants who progressed to Kidney Malfunction. The percentage of participants progressing to kidney malfunction will be reported based on one of the following, 1. ≥ 40% reduction in eGFR sustained for ≥ 30 days; 2. eGFR < 15 mL/min/1.73m2 for ≥ 30 days; 3. Undergoing dialysis for ≥ 30 days; 4. Undergoing kidney transplantation; 5. Died from kidney failure
3. Percentage of participants requiring rescue therapy
4. Felzartamab serum concentrations over time
5. Number of patients with anti-drug antibodies (ADAs) against felzartamab
6. Percentage of Participants With Treatment Emergent Adverse Event (TEAE) and Treatment Emergent Serious Adverse Event (TESAE)
7. Number of Participants With Clinically Significant Change From Baseline in Vital Signs Abnormalities
8. Number of Participants With Clinically Significant Change From Baseline in Physical Examination Abnormalities
9. Percentage of participants Achieving complete response (CR) CR is defined as UPCR value (based on 24-hour urine collection) of <0.5 gram per gram (g/g), a reduction in UPCR of ≥50%, and a stable eGFR (decrease from baseline in eGFR of ≤25%)
10. Change in Baseline in EGFR Values Calculated Using the CKD-EPI Creatinine Equation
11. Number of Participants With Clinically Significant Change From Baseline in Laboratory Abnormalities
12. Number of Participants With Clinically Significant Change From Baseline in Electrocardiogram (ECG) Abnormalities

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Auxiliary 9

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Biogen Idec Research Limited

Sponsor organisation

Biogen Idec Research Limited

Address

Building 5 Foundation Park, Roxborough Way Roxborough Way

City

Maidenhead

Postcode

SL6 3UD

Country

United Kingdom

Scientific contact point

Organisation

Biogen Idec Research Limited

Contact name

Clinical Trials Information Desk

Public contact point

Organisation

Biogen Idec Research Limited

Contact name

Clinical Trials Information Desk

Third parties 11

Locations

11 EU/EEA countries · 86 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 298 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

5 submissions — initial application plus substantial / non-substantial modifications