Alcoholic hepatitis is a syndrome of progressive inflammatory liver injury associated with long-term heavy intake of ethanol. The pathogenesis is not completely understood. Patients who are severely affected present with subacute onset of fever, hepatomegaly, leukocytosis, marked impairment of liver function (e.g., jaundice, coagulopathy), and manifestations of portal hypertension (e.g., ascites, hepatic encephalopathy, variceal hemorrhage). However, milder forms of alcoholic hepatitis often do not cause any symptoms. Alcoholic hepatitis usually persists and progresses to cirrhosis if heavy alcohol use continues. If alcohol use ceases, alcoholic hepatitis resolves slowly over weeks to months, sometimes without permanent sequelae but often with residual cirrhosis. F-652 is a recombinant fusion protein containing human interleukin 22 (IL-22) and human Immunoglobulin G2 (IgG2)-Fc produced in CHO cells in serum-free culture. F-652 under development is intended to treat patients with graft vs host disease (GvHD) after bone marrow transplantation, and acute alcoholic hepatitis (AAH), a severe form of alcoholic liver disease (ALD). Both GvHD and AAH are diseases with unmet medical need. The current investigational new drug (IND) application is to conduct a phase Ia clinical study in GvHD patients to evaluate the safety and pharmacokinetic profile, and biomarkers of F-652 treatment by intravenous infusion (IV). IL-22 is a member of the IL-10 family of cytokines which control bacterial infection, homeostasis, and tissue repair. IL-22 may be used to treat patients with ALD because of its antioxidant, anti-apoptotic, anti-steatotic, anti-microbial, and proliferative effect that have been demonstrated in various experimental systems.