A Phase 3 Study of Obexelimab in Patients With IgG4-Related Disease

Overview

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

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).

Eligibility

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