A real-world study focused on the long-term efficacy of mycophenolate mofetil as first-line treatment of autoimmune hepatitis

Background Front-line therapy with mycophenolate mofetil (MMF) in autoimmune hepatitis (AIH) has shown high on-treatment remission rates. Aim To study prospectively in a real-world fashion the long-term outcome of a large group of consecutive treatment-naiive AIH patients. Methods Between 2000 and 2014, 158 patients were recruited but only 131 were eligible for treatment (109 MMF/prednisolone; 22 prednisolone +/- azathioprine). Long-term data on outcome after drug withdrawal were evaluated. Patients stopped treatment after having achieved complete response (normal transaminases and IgG) for at least the last 2 years. Results At diagnosis, 31.6% of patients had cirrhosis and 72.8% insidious presentation. A total of 102 of 109 (93.6%) responded initially to MMF within 2 (1-18) months. A total of 78 of 109 (71.6%) had complete response on treatment and 61 of 78 (78.2%) maintained remission off prednisolone. MMF-treated patients had increased probability of complete response compared to those receiving azathioprine (P = 0.03). Independent predictors of complete response were lower ALT at 6 months (P = 0.001) and acute presentation (P = 0.03). So far, treatment withdrawal was feasible in 40/109 patients and 30 (75%) are still in remission after 24 (2-129) months. Remission maintenance was associated with longer MMF treatment (P = 0.005), higher baseline ALT (P < 0.02), lower IgG on 6 months (P = 0.004) and histological improvement. Conclusions Mycophenolate mofetil proved to be an efficient first-line treatment for AIH, achieving so far the highest rates of remission maintenance off treatment (75%) ever published for at least a median of 2 years, although the remission criteria used were strict. However, the risk of potential bias and overestimation of intervention benefits from MMF cannot be completely excluded, as this is a real world and not a randomised controlled trial.