Inebilizumab for the Treatment of Patients With Type 1 Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP) is an immune-related inflammatory disease of the pancreas. Relapse can occur after treatment, and long-term treatment with glucocorticoids and conventional immunosuppressants can cause significant side effects. This multicenter, single-arm, open-label study aims to evaluate the efficacy and safety of inebilizumab in patients with AIP. Inebilizumab targets CD19 and reduces B cells, including plasmablasts. The study plans to enroll 50 patients with confirmed AIP, including both newly diagnosed patients and patients with relapsing disease. All eligible participants will receive inebilizumab and follow a standardized glucocorticoid dose-reduction regimen. The primary objective is to assess whether inebilizumab can reduce the relapse rate within 32 weeks. Secondary objectives are to assess its effects on glucocorticoid use, serum IgG4 levels, B-cell counts, and other immune cells. Peripheral blood samples and lymph node samples will be collected for exploratory mechanistic analyses to characterize circulating and tissue immune-cell populations and blood-based biomarkers during treatment and follow-up.

Inclusion Criteria: 1. A signed and dated informed consent form; 2. A commitment to adhere to the study protocol and to cooperate throughout the entire study; 3. Aged 18 years or over, regardless of gender; 4. Diagnosed with Type I AIP; 5. Indications for treatment: (1) For symptomatic participants, evidence of pancreatic involvement (e.g. obstructive jaundice, abdominal pain, lower back pain) and extra-pancreatic organ involvement (e.g. jaundice caused by bile duct stricture); (2) Asymptomatic participants with subclinical AIP that may progress to severe, irreversible damage to vital organs (e.g. persistent pancreatic mass, abnormal liver function accompanied by proximal IgG4-related sclerosing cholangitis); 6. Be able to adhere to and cooperate with study interventions, such as taking oral medication; 7. If a woman of childbearing potential, she must have used contraception for at least one month prior to screening and undertake to use contraception throughout the study period and for a specified period following the study's conclusion; Exclusion Criteria: Participants meeting any of the following criteria will be excluded from this study: 1. Women who are trying to conceive, are pregnant or are breastfeeding; 2. Those who are unable or refuse to sign the informed consent form; 3. History of mental illness; 4. Allergy to the study intervention; 5. Concurrent malignant tumours; 6. Infectious diseases such as active hepatitis or tuberculosis; 7. Concurrent uncontrolled underlying conditions, such as severe heart failure or respiratory failure.