Nonstandard Drugs and Feasible New Interventions for Autoimmune Hepatitis: Part I

Albert      J. Czaja

Abstract

Nonstandard drugs that target critical pathogenic pathways or immune regulatory mechanisms constitute the next generation of treatments for autoimmune hepatitis. Mycophenolate mofetil impairs the proliferation of lymphocytes, decreases autoantibody production, and induces apoptosis of activated immunocytes. Patients treated for azathioprine intolerance improve more frequently than patients treated for refractory liver disease (54% versus 10%), and mycophenolate mofetil is emerging as a rescue therapy for this population. Complete corticosteroid withdrawal is possible in 40% of patients treated with mycophenolate mofetil, and the frequency of side effects ranges from 3-34%. Budesonide in combination with azathioprine has normalized liver tests more frequently (47% versus 18%) and with fewer side effects (28% versus 53%) than standard therapy after 6 months. Budesonide is emerging as a frontline treatment in non-cirrhotic patients with uncomplicated disease or contraindications to conventional corticosteroids. Cyclosporine and tacrolimus are effective salvage agents for steroid-refractory disease, but side effects have been common and occasionally serious. The 6- thioguanine nucleotides and rapamycin are feasible treatments for autoimmune hepatitis, but 6-thioguanine has major obstacles to overcome, especially the risk of liver toxicity or nodular regenerative hyperplasia. The nonstandard drug therapies emerging for autoimmune hepatitis reflect the need to supplement or supplant current treatment regimens. None has been licensed for use in autoimmune hepatitis, and their applications have been based on results from small singlecenter experiences.

Keywords: Autoimmune hepatitis, nonstandard drugs, rescue agents, salvage therapy, Corticosteroids, mycophenolate mofetil, azathioprine, steroid-refractory diseases, Budesonide, 6-thioguanine.