- Presence of Hepatitis B surface antigen (HBsAg) at screening Positive Hepatitis C antibody test result at screening or within 3 months prior to first dose. As potential for and magnitude of immunosuppression with this compound is unknown, subjects with presence of hepatitis B core antibody (HBcAb) should be excluded. Subjects positive for HBsAg and/or positive for anti-HBc antibody (regardless of anti-HBs antibody status) are excluded.