The purpose of this study is to test the safety and efficacy of Civacir® to prevent the recurrence of Hepatitis C Virus (HCV) after liver transplant.

Civacir® 10%, Hepatitis C Immune Globulin Intravenous (Human) is a high-titer human polyclonal immune globulin (IgG) containing a diversity of antibodies that target and bind the hepatitis C virus (HCV) to prevent infection. Subjects who reduce their viral load to less than 100 IU/ml HCV RNA through up to 24 weeks of antiviral therapy prior to liver transplant are enrolled in the study. There is no requirement to reach undetectable virus prior to transplant as the function of Civacir® is to neutralize any remaining virus in circulation.

Subjects randomized to Civacir® treatment arms receive study drug infusions starting on the day of liver transplant followed by 15 doses over a 10 week period to prevent the recurrence of quantifiable Hepatitis C Virus (HCV) after liver transplant. The study will evaluate dosing arms ranging from 200 mg/kg to 300 mg/kg compared to a control arm. For the primary endpoint, efficacy is defined as persistent viral load suppression maintaining HCV RNA levels below the lower limit of quantitation as determined by central laboratory Polymerase Chain Reaction (PCR) at 22 weeks post-liver transplant and then at 34 weeks post-liver transplant to demonstrate durability of effect.

Inclusion Criteria:

• Written informed consent obtained prior to any study-specific assessments and within 3 months (reconsent) of orthotopic liver transplantation (OLT).
• HCV Genotype 1 through 6 Infection.
• Subjects in the beginning of a new antiviral therapy regimen (regardless of prior treatment failures) for up to and including 24 weeks prior to the day of OLT.
• Most recent evidence within the last 4 weeks that HCV RNA is <100 IU/mL. Subjects may be randomized based on local lab HCV RNA.
• Male and female subjects (age 18-80 years).
• Subject weight under 250 pounds.
• Stable patient in a condition which in the opinion of the investigator would permit safe participation in the study.

Exclusion Criteria:

• Re-transplantation due to viral recurrence.
• Positive HIV or HBV test within 90 days prior to transplantation.
• Most recent PCR test indicating HCV RNA ≥100 IU/mL within 4 weeks of OLT.
• Subjects having received organs from HCV positive donors.
• Serum creatinine level >2.5 times the upper limit of normal or advanced renal disease at screening.
• Pregnancy or single contraceptive measure or lactation period (females only).
• Known intolerance to immunoglobulins or comparable substances (e.g. vaccination reaction).
• Known absolute Immunoglobulin A (IgA) deficiency.
• Known intolerance to proteins of human origin.
• Participation in another clinical trial within 90 days before signing Informed Consent Form (ICF) or during the study (observational/ non-interventional and 988 studies allowed), and/or previous participation in 988 study (except for Study 988 screen failures).
• Active drug and/or alcohol abuse.
• Inability or lacking motivation to participate in the study.