Azathioprine in Autoimmune Hepatitis Treatment

Standard Treatment Regimens

The American Association for the Study of Liver Diseases recommends prednisone/prednisolone plus azathioprine as the standard combination therapy for AIH, providing equivalent efficacy to prednisone alone but with significantly fewer steroid-related side effects (10% vs 44%) 2, 3
The typical dosing regimen for adults includes prednisone starting at 30mg/day and gradually tapering to 10mg/day maintenance, and azathioprine at 50mg/day (USA) or 1-2mg/kg/day (Europe) 4, 5

The European Association for the Study of the Liver suggests that patients who will be treated continuously for at least 6 months are ideal candidates for combination therapy 2
Individuals at higher risk for steroid-related complications, such as postmenopausal women, patients with emotional instability, pre-existing osteoporosis, brittle diabetes, labile hypertension, obesity, and young female patients concerned about weight gain and cosmetic side effects, may benefit from azathioprine therapy 1, 2, 3

The American Association for the Study of Liver Diseases recommends pretreatment testing for TPMT activity, especially in patients with pretreatment cytopenia 2
Azathioprine side effects occur in <10% of patients receiving 50mg daily and can include cholestatic hepatitis, veno-occlusive disease, pancreatitis, nausea and vomiting, rash, and bone marrow suppression 2, 4, 5, 6

The goal of therapy is complete biochemical and histological remission, and after achieving normal aminotransferases and IgG levels, prednisolone can be reduced to 7.5mg/day, then to 5mg/day after three months, with further tapering at 3-4 month intervals 1
For maintenance therapy after relapse, options include continuing low-dose prednisone (median 7.5mg daily) or increasing azathioprine to 2mg/kg daily as a steroid-sparing strategy 4, 6

The European Association for the Study of the Liver suggests that mycophenolate mofetil (MMF) is the second-line drug of choice for patients intolerant to azathioprine 7

In patients with features of both AIH and primary sclerosing cholangitis (PSC), combination therapy with UDCA and immunosuppression (prednisolone and azathioprine) is recommended 7
All children diagnosed with AIH should be treated due to the typically more aggressive course of disease in pediatric patients 5