This study aims to examine the efficacy and safety of obexelimab for the prevention of flare of IgG4-related disease (IgG4-RD)



Eligible Ages
Over 18 Years
Eligible Genders
Accepts Healthy Volunteers

Inclusion Criteria

  1. Males and females, ≥ 18 years of age 2. Clinical diagnosis of IgG4-RD 3. Patients must meet the 2019 ACR/EULAR Classification Criteria for IgG4-RD 4. Patients must have active IgG4-RD signs/symptoms (i.e., flare) that require the initiation of GC therapy or the increase in background long-term GC therapy 5. Other inclusion criteria apply

Exclusion Criteria

  1. Has disease in only 1 organ system whose primary manifestation is fibrosis 2. Has received prednisone equivalent given orally at a dose greater than 60 mg/day within the 4 weeks prior to screening or during screening 3. Has received a non-biologic, disease-modifying anti-rheumatological drug or immunosuppressive agent other than GCs within the 4 weeks prior to screening 4. Has received an investigational treatment or direct medical intervention on another clinical study within 12 weeks or < 5 half-lives of the investigational treatment, whichever is shorter, prior to screening 5. Has received live vaccine or live therapeutic infectious agent within the 2 weeks prior to screening 6. Active tuberculosis or high risk for tuberculosis; hepatitis C infection in absence of curative treatment; evidence of hepatitis B infection 7. Use of B cell depleting or targeting agents within 6 months of randomization 8. Other exclusion criteria apply

Study Design

Phase 3
Study Type
Intervention Model
Parallel Assignment
Primary Purpose
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)

Arm Groups

ArmDescriptionAssigned Intervention
Obexelimab administered as an SC injection.
  • Drug: Obexelimab
    Obexelimab is a monoclonal antibody that simultaneously binds CD19 and FcγRIIb, resulting in down regulation of B cell activity.
Placebo Comparator
Placebo administered as an SC injection.
  • Other: Placebo

Recruiting Locations

Massachusetts General Hospital
Boston, Massachusetts 02114

More Details

Zenas BioPharma (USA), LLC

Study Contact

Patient and Medical Information

Detailed Description

This study consists of a 1-year randomized control period (RCP), followed by an additional 1-year open label extension (OLE) period. To enter the Screening Period (Day -28 to Day -1), patients must have active IgG4-RD signs/symptoms (i.e., flare) that require steroid therapy. On Day 1, patients will be randomized in a ratio of 1:1 to receive either obexelimab or placebo administered as subcutaneous (SC) injections. All patients will begin a steroid taper on Day 1 to discontinuation by Week 8. Patients will be monitored for flares during scheduled in clinic visits and any unscheduled visits. The primary endpoint is time to first IgG4-RD flare that requires initiation of rescue therapy in the opinion of the investigator and the Adjudication Committee (AC). Following the 52-week RCP, patients will have the opportunity to continue in an OLE period where all patients will receive obexelimab. Patients who do not wish to enroll into the OLE period will return for an in-clinic safety follow-up visit 8 weeks after the Week 52 visit (i.e., Week 60). Including screening and follow-up, the maximum duration of participation in this study for an individual patient is 116 weeks (i.e., 28-day screening, 52-week RCP, 52-week OLE, and an 8-week follow-up).


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.