Treatment Updates for Type 1 Autoimmune Pancreatitis and IgG4-Related Diseases

Authors

  • Yasmin G. Hernandez-Barco, MD Division of Gastroenterology, Massachusetts General Hospital, Boston, MA; Harvard Medical School, Boston, MA Author
  • Cory A. Perugino, DO Division of Rheumatology, Massachusetts General Hospital, Boston, MA; Harvard Medical School, Boston, MA; Author

DOI:

https://doi.org/10.69734/8p34ma30

Keywords:

autoimmune pancreatitis, type 1 AIP, IgG4-related disease, B-cell therapy, rituximab, inebilizumab, obexelimab, glucocorticoids, relapse prevention, pancreatobiliary disease;, HISORt criteria, endoscopic ultrasound, fine-needle biopsy, BTK inhibitors, rilzabrutinib, zanubrutinib, FcRn blockade, efgartigimod, CAR-T therapy, CD19, BCMA

Abstract

Type 1 autoimmune pancreatitis (AIP) is the pancreatic manifestation of IgG4-related disease. Glucocorticoids induce remission but relapse is common and toxicity limits maintenance use. Conventional immunosuppressants have a modest steroid-sparing role when B-cell therapy is unavailable. Rituximab is effective but off-label. Inebilizumab, a CD19-depleting antibody, is FDA-approved for adult IgG4-RD after MITIGATE showed an 87% reduction in adjudicated flares. Obexelimab, a nondepleting CD19/FcγRIIb inhibitor, reduced flare risk and glucocorticoid exposure in INDIGO; a BLA is under review. BTK inhibitors, FcRn blockade, and cellular therapies remain investigational. Treatment should be guided by organ burden, relapse risk, and comorbidity rather than a default steroid course for every patient. 

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Published

2026-09-22

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Vol. 3 No. 3 (2026): SMART-MD Journal of Precision Medicine Vol 3, No 3, (Summer) 2026

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SMART Approach

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How to Cite

Hernandez-Barco, Y., & Perugino, C. A. (2026). Treatment Updates for Type 1 Autoimmune Pancreatitis and IgG4-Related Diseases. SMART-MD Journal of Precision Medicine, 3(3), e265 to e273. https://doi.org/10.69734/8p34ma30