Human Hepatitis B Immunoglobulin
Overview
Human Hepatitis B immunoglobulin is a biologic preparation of purified human immunoglobulin enriched with antibodies against hepatitis B virus surface antigen, intended to provide passive immunity following exposure to the virus. It belongs to the class of immunoglobulin preparations derived from pooled human plasma donors with high anti-hepatitis B antibody levels and is used primarily for post-exposure prophylaxis and prevention of reinfection in certain high-risk scenarios. The immunoglobulin acts by supplying ready-made antibodies that neutralize the hepatitis B virus and reduce the likelihood of viral replication and establishment of infection. It is used alongside active hepatitis B vaccination in post-exposure settings to provide immediate protection while the vaccine initiates a longer-term adaptive immune response. This preparation can be administered by intramuscular injection for post-exposure prophylaxis and by intravenous infusion in some clinical contexts. Human Hepatitis B immunoglobulin plays a critical role in reducing the risk of hepatitis B transmission after accidental exposure and in managing patients undergoing liver transplantation for hepatitis B-related disease.
Background and Date of Approval
In the United States, human hepatitis B immune globulin preparations such as HepaGam B were first approved by the Food and Drug Administration in 2006 for treatment after acute exposure to hepatitis B virus and for prevention of reinfection following liver transplantation. Regulatory authorities worldwide have approved hepatitis B immunoglobulin for post-exposure prophylaxis in persons exposed to hepatitis B surface antigen-positive blood or body fluids and for prevention of perinatal transmission. Approval has been based on clinical evidence supporting the effectiveness of passive immunization when administered promptly after exposure. The product is licensed as a blood-derived biologic under established safety and potency standards.
Uses
Human Hepatitis B Immunoglobulin is indicated for post-exposure prophylaxis in individuals exposed to hepatitis B virus through percutaneous injury, mucous membrane exposure, sexual exposure, or close household contact with infected individuals. It is also indicated for prevention of hepatitis B virus reinfection in recipients of liver transplants for hepatitis B-related disease. In newborns born to mothers who are hepatitis B surface antigen positive, it is administered soon after birth together with hepatitis B vaccination to reduce the risk of vertical transmission. Administration of immunoglobulin forms part of combined passive and active immunization strategies to provide immediate antibody protection and initiate longer-term vaccine-mediated immunity.
Administration
Human Hepatitis B Immunoglobulin is administered by intramuscular injection for post-exposure prophylaxis and by intramuscular or intravenous routes depending on product formulation and clinical context. For post-exposure prophylaxis in unvaccinated individuals, the recommended dose is approximately 0.06 milliliters per kilogram of body weight given as soon as possible after exposure, ideally within 24 hours. It should be administered at a site separate from where the hepatitis B vaccine is given. In newborns of hepatitis B surface antigen-positive mothers, a standard dose such as 0.5 milliliter is given intramuscularly within 12 hours of birth along with the first dose of hepatitis B vaccine. For prevention of reinfection after liver transplantation, larger doses may be administered intravenously to achieve and maintain protective antibody levels, with dosing adjusted based on antibody titers and clinical response.
Side Effects
Common side effects following administration include mild pain, tenderness, redness, or swelling at the injection site. Some individuals may experience headache, mild fever, fatigue, nausea, or general discomfort. These reactions are usually mild and resolve without specific treatment.
Warnings
Serious adverse events are uncommon but may include hypersensitivity reactions, including severe allergic responses such as anaphylaxis. Individuals with known IgA deficiency or a history of severe reactions to human immunoglobulin preparations require careful evaluation. Intramuscular administration in patients with bleeding disorders should be approached cautiously. Immediate medical attention is required if signs of severe allergic reaction occur.
Precautions
Before administration, clinicians should review the patient’s vaccination history, exposure details, and allergy history. Human Hepatitis B Immunoglobulin should be administered at a different anatomical site from hepatitis B vaccine when given concurrently. It may interfere with the immune response to certain live virus vaccines, and timing adjustments may be necessary. Patients with immunocompromised conditions may require individualized follow-up and monitoring of antibody levels.
Expert Tips
Effective use requires prompt administration after confirmed or suspected exposure. Accurate weight-based dosing enhances effectiveness in post-exposure settings. In newborn prophylaxis, ensure administration within the recommended time window after birth. Monitor patients briefly after injection for immediate reactions. Documentation of dose, batch number, route, and timing is important for clinical records. Coordinate passive immunization with completion of the full hepatitis B vaccine series for long-term protection.