Safety and Efficacy of Abatacept in IgG4-Related Disease

Inclusion Criteria

• Are male or female 18 years of age or older
• Meet the American College of Rheumatology (ACR)/EULAR 2018 Classification Criteria for IgG4-RD
• Have active disease based on an IgG4-RD Responder Index (RI) ≥2 at screening with disease manifestation in at least one organ system excluding lymph nodes at screening
• May or may not have received prior IgG4-RD therapy
• Must be willing to taper off any systemic corticosteroid therapy within 4 weeks of first dose of trial drug.
• Must be able and willing to discontinue any immunosuppressive agent at screening (e.g. methotrexate, mycophenolate mofetil, 6-mercaptopurine, tacrolimus, cyclophosphamide or azathioprine).
• No history of severe allergic reactions to monoclonal antibodies.
• Are able and willing to complete the entire study according to the study schedule.
• Are willing to forego other forms of experimental treatment during the study.
• Are able to provide written informed consent.

Exclusion Criteria

• History or evidence of a clinically unstable/uncontrolled disorder, condition or disease (including but not limited to cardiopulmonary, oncologic, renal, hepatic, metabolic, hematologic or psychiatric) other than IgG4-RD that, in the opinion of the Investigator, would pose a risk to patient safety or interfere with the study evaluation, procedures or completion.
• Malignancy within 5 years (except successfully treated in situ cervical cancer, resected squamous cell or basal cell carcinoma of the skin, or prostate cancer with no recurrence ≥3 years following prostatectomy).
• Liver disease: Acute or chronic non-IgG4-related liver disease deemed sufficiently severe to impair their ability to participate in the trial.
• Uncontrolled disease: evidence of another uncontrolled condition, including drug and alcohol abuse, which could interfere with participation in the trial according to the protocol.
• Presence of recurrent or chronic infections, defined as ≥3 infections requiring antimicrobials over the past 6 months prior to screening.
• Active infection requiring hospitalization or treatment with parenteral antimicrobials within the 30 days prior to randomization.
• Prior use of rituximab (or other B cell depleting agents) within 6 months of enrollment unless B cells have been demonstrated to have repopulated.
• Use of any investigational agent within 5 half-lives of the agent (or 6 months if the half-life is unknown) prior to enrollment.
• White blood cell count 2.0 mg/dL.
• Hemoglobin < 10 g/dL.
• Platelet count < 75 x 109/L.
• Known positive result for HIV I or II antibody, hepatitis B surface antigen, hepatitis B core antibody or hepatitis C antibody.
• Has received live vaccines within 4 weeks of enrollment.
• Inability to communicate reliably with the investigator.
• Patient is pregnant or breast feeding, or planning to become pregnant while enrolled in the study, up to end of study (EOS) visit.
• Positive pregnancy test at screening or during the study.
• Subjects who do not agree to use medically acceptable methods of contraception.
• Male patient with a pregnant partner who is not willing to use a condom during the treatment and up to end of study (EOS)visit.
• Known or suspected sensitivity to mammalian cell-derived products or any components of the study drug.
• History of alcohol and/or substance abuse within 12 months prior to screening.
• Unable or unwilling to partake in follow-up assessments or required protocol procedures.