IgG4-Related Disease Clinical Trials and Treatments

IgG4-related disease was recognized as a unified clinical entity only in 2003, when Japanese researchers linked autoimmune pancreatitis to a systemic condition with IgG4-positive tissue infiltration in multiple organs. The pathophysiology involves aberrant T follicular helper cells driving IgG4 class switching in B cells, CD4+ cytotoxic T lymphocytes that infiltrate tissues and produce profibrotic cytokines, and activated fibroblasts that deposit collagen in a characteristic whorled (storiform) pattern. Diagnosis requires tissue biopsy in most cases, with histopathological criteria including dense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis.

The most common symptoms of IgG4-Related Disease include Painless swelling of salivary or lacrimal (tear) glands, Pancreas inflammation that can mimic pancreatic cancer on imaging, Kidney dysfunction from tubulointerstitial nephritis, Retroperitoneal fibrosis causing back pain and ureteral obstruction, Sclerosing cholangitis (bile duct narrowing) causing jaundice, among others. Approximately 5 in 100,000 people; an estimated 57,000 diagnosed individuals in the U.S. as of 2024. Symptoms can range from mild to severe and may vary between individuals.

Trial Friend lists all active clinical trials for IgG4-Related Disease from ClinicalTrials.gov, with eligibility criteria translated into plain English. Patients can filter by trial phase and recruitment status, search by location, and use the Match Me tool to score trials against their profile. The approval of inebilizumab (Uplizna) in April 2025 was a turning point for IgG4-RD, but research is far from over. Trials are studying optimal duration of B-cell depletion therapy, whether early aggressive treatment prevents irreversible fibrosis, and how to manage the subset of patients who relapse despite B-cell targeted therapy.

Yes. As of September 2026, Trial Friend lists 1 FDA-approved drug used to treat IgG4-Related Disease: Uplizna (inebilizumab), first approved in 2025.

Each has its own page with what the label covers, side effects and how it is given, and the Treatments section of this page adds any further approved drugs found in FDA labeling data.

The FDA is due to decide on Obexelimab by May 27, 2027; the FDA calendar page carries the outcome the day it lands.

The exact cause of IgG4-Related Disease is not fully understood. It is not caused by a single gene; inherited variants raise risk, and immune, environmental or other triggers are thought to set it off. Cause is unclear; genetic background, infection and autoimmunity are all implicated, and no genetic test has a diagnostic role. Approximately 5 in 100,000 people; an estimated 57,000 diagnosed individuals in the U.S. as of 2024. Research is ongoing to better understand the disease mechanism.

No single gene test diagnoses IgG4-Related Disease. The diagnosis rests on clinical findings and laboratory or imaging results; genetic variants shift risk rather than cause the disease. Cause is unclear; genetic background, infection and autoimmunity are all implicated, and no genetic test has a diagnostic role.

Some trials collect genetic samples for research or check specific risk markers. The Genetic Testing section of this page shows any tests listed in the NIH Genetic Testing Registry, which for this condition are usually research or risk-marker tests rather than diagnostic ones.

Eligibility for IgG4-Related Disease clinical trials depends on factors like age, diagnosis, treatment history, and overall health. Each trial sets its own inclusion and exclusion criteria. Trial Friend translates these requirements from medical language into plain English so patients can review them more easily. The Match Me tool can score your profile against active trials to help identify studies that may be a fit.

Participating in a IgG4-Related Disease clinical trial typically involves scheduled visits, medical tests, and close monitoring by a research team. Depending on the study phase, you may receive an investigational treatment, a placebo, or the current standard of care. Trials may last from a few weeks to several years. Study participation is voluntary, and you can withdraw at any time.