IgG4-related Disease (IgG4-RD) is a condition where the immune system attacks the body's own tissues, causing inflammation and swelling in various organs. This study is testing a new medicine, rilzabrutinib, to see if it can help adults with IgG4-RD feel better compared to a placebo (a pill with no medicine). It's a randomized, double-blind study, meaning participants and doctors won't know who is getting the real medicine. The study will last for about 60 weeks, including a screening period, 52 weeks of treatment, and follow-up. There might be an additional 108 weeks of optional treatment.
- Participants will need to visit the study center 16 times, with an option for 9 more visits if they continue treatment.
- The study will monitor how long it takes for the disease symptoms to come back.
- Safety checks include monitoring for side effects and regular health tests.