Description
Hepatitis B Immune Globulin (Human), Nabi-HB, is a sterile solution of immunoglobulin (5 ± 1% protein) containing antibodies to hepatitis B surface antigen (anti-HBs). It is prepared from plasma donated by individuals with high titers of anti-HBs. The plasma is processed using a modified Cohn 6 / Oncley 9 cold-alcohol fractionation process1,2 with two added viral reduction steps described below. Nabi-HB is formulated in 0.042-0.108 M sodium chloride, 0.10-0.20 M glycine, and 0.005-0.050% polysorbate 80, at pH 5.8-6.5. The product is supplied as a nonturbid sterile liquid in single dose vials and appears as clear to opalescent. It contains no preservative and is intended for single use by the intramuscular route only.
Each plasma donation used for the manufacture of Nabi-HB is tested for the presence of hepatitis B virus (HBV) surface antigen (HBsAg), human immunodeficiency viruses (HIV) 1/2, and hepatitis C virus (HCV) antibodies. In addition, pooled samples of Source Plasma used in the manufacture of this product are tested by FDA licensed Nucleic Acid Testing (NAT) for HIV and HCV and found to be negative. Investigational NAT for hepatitis A virus (HAV) and HBV is also performed on pooled samples of all Source Plasma used, and found to be negative; however, the significance of a negative result has not been established. Investigational NAT for parvovirus B19 (B19) is also performed on pooled samples of all Source Plasma and the limit for B19 DNA in a manufacturing pool is set not to exceed 104 IU/mL.
The manufacturing steps for Nabi-HB are designed to reduce the risk of transmission of viral disease. The solvent/detergent treatment step, using tri-n-butyl phosphate and Triton® X-100, is effective in inactivating known enveloped viruses such as hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV)3. Virus filtration, using a Planova® 35 nm Virus Filter, is effective in reducing some known enveloped and non-enveloped viruses4. The inactivation and reduction of known enveloped and non-enveloped model viruses were validated in laboratory studies as summarized in the following table:
| BVD = Bovine Viral Diarrhea Virus EMC = Encephalomyocarditis Virus HIV = Human Immunodeficiency Virus | PVB19 = Parvovirus B19 PPV = Porcine Parvovirus PRV = Pseudorabies Virus | NT = not tested * Value not included in cumulative clearance | |||
| Test Virus | |||||
HIV | BVD | PRV | EMC | PPV | |
| Model Virus: | HIV | HCV | HBV | Hepatitis A | PVB19 |
| Envelope/Genome: | yes/RNA | yes/RNA | yes/DNA | no/RNA | no/DNA |
| Manufacturing Step | |||||
Precipitation of Cohn Fraction III | >5.9 | 3.6 | 3.7 | 4.4 | 3.9 |
| Cuno Filtration | NT | NT | NT | >6.6 | 5.4 |
| Solvent/Detergent | >4.2 | >6.9 | >6.4 | NT | NT |
| Nanofiltration | >7.4 | >6.9 | >5.7 | 3.0 | 0.7* |
| Cumulative | >17.5 | >17.4 | >15.8 | >14.0 | 9.3 |
Product potency is expressed in international units (IU) by comparison to the World Health Organization (WHO) standard. Each milliliter (mL) of product contains greater than 312 IU anti-HBs. The potency of each milliliter of Nabi-HB exceeds the potency of anti-HBs in a U.S. reference hepatitis B immune globulin (FDA). The U.S. reference has been tested by Biotest Pharmaceuticals against the WHO standard and found to be equal to 208 IU/mL.