Able and willing to complete the entire study according to the study schedule
Able and willing to provide written informed consent
You may not be if
History or evidence of a clinically unstable/uncontrolled disorder, condition or disease other than IgG4-RD that, in the opinion of the Investigator would pose a risk to the 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)
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 60 days prior to randomization or oral antimicrobials within the 21 days prior to enrollment
Patient is taking \>40 mg of prednisone QD
Prior use of rituximab (or other B cell depleting agents) within 6 months of enrollment. Prior use of any B cell depleting agent greater than 6 months from enrollment is allowed if the CD19+ B cell count is within the normal reference range during screening
Use of any investigational agent within 5 half-lives of the agent (or 6 months if the half-life is unknown) prior to enrollment
Immunosuppressive agent use within the three months prior to enrollment
Has received live vaccines within 2 months of enrollment
Patient is pregnant or breast feeding, or planning to become pregnant while enrolled in the study, up to end-of-study visit
Unable or unwilling to partake in the follow-up assessments or required protocol procedures
