Hepatitis B Adult Vaccine

Introduction Overview

Generic Name

hepatitis B adult vaccine

Brand Name

Engerix-B (HepB)
Heplisav-B
Recombivax HB Adult
Recombivax HB Dialysis Formulation
Recombivax HB Adult Dialysis Formulation
PreHevbrio

Dosage Form

intramuscular solution (20 mcg/0.5 mL)
intramuscular suspension (10 mcg/mL)
intramuscular suspension (20 mcg/mL)
intramuscular suspension (dialysis 40 mcg/mL)

Drug Class

viral vaccines

Pharmacokinetics

Absorption:
The hepatitis B adult vaccine is administered intramuscularly, typically into the deltoid muscle, facilitating direct absorption into the lymphatic system and systemic circulation. Since the vaccine consists of recombinant hepatitis B surface antigen (HBsAg), absorption is characterized by the prompt uptake by antigen-presenting cells at the injection site rather than classical absorption seen with small-molecule drugs. The vaccine antigens are processed locally before inducing systemic immune response, with minimal systemic presence of the antigen itself. Factors such as injection technique and muscle mass may influence antigen presentation and subsequent immunogenicity.

Distribution:
Following administration, the antigen primarily remains localized at the injection site and regional lymph nodes. There is negligible systemic distribution of the vaccine antigen. Instead, antigen-presenting cells migrate to lymphoid tissues to activate T and B lymphocytes, initiating adaptive immunity. The vaccine does not distribute broadly across tissues like conventional drugs, but its immunogenic proteins engage with dendritic cells and macrophages to initiate the immune cascade. Systemic exposure to vaccine compounds is minimal, avoiding extensive tissue distribution.

Metabolism:
The hepatitis B vaccine contains recombinant HBsAg proteins. These protein antigens are metabolized by proteolytic enzymes within antigen-presenting cells and regional tissues after uptake. The peptides are processed and presented to T cells, inducing immunity. The metabolism thus involves enzymatic breakdown within immune cells rather than hepatic metabolism typical for small-molecule drugs. Adjuvants used in some vaccine formulations enhance antigen uptake and facilitate a robust immune response without systemic metabolic interactions. There is no involvement of cytochrome P450 enzymes or hepatic pathways.

Elimination:
The vaccine components, mainly protein antigens, are degraded by immune cells and cleared via normal proteolytic pathways. There is no renal or hepatic elimination of the vaccine in its intact form. The immunological memory produced persists long term, with booster doses recommended in certain situations to maintain immunity. The vaccine does not demonstrate classical elimination kinetics but relies on the immune system's ability to process and present antigen leading to memory B and T cell generation. Clinical data indicate durable protection with standard dosing schedules, with elimination of antigen fragments occurring locally.

Dosage Forms

Available Dosage Forms:
- Intramuscular solution: 20 mcg per 0.5 mL prefilled syringe or vial.
- Intramuscular suspension formulations:
-- 10 mcg/mL suspension
-- 20 mcg/mL suspension
-- 40 mcg/mL suspension for dialysis patients (Recombivax HB Dialysis Formulation)

Dosages for Adults and Adolescents:
- Engerix-B (Recombinant):
-- For adults 20 years and older: three doses of 1 mL each intramuscularly at 0, 1, and 6 months.
-- For adolescents 19 years and younger: three doses of 0.5 mL intramuscularly on a 0, 1, and 6 month schedule.
- Heplisav-B:
-- Two doses of 0.5 mL each intramuscularly, administered one month apart.
- Recombivax HB Adult:
-- Adults 20 years and older: three doses of 1 mL intramuscularly, on a 0, 1, and 6 month schedule.
-- Adolescents 19 and younger: three doses of 0.5 mL intramuscularly, using pediatric/adolescent formulation.
- Dialysis Formulations:
-- Recombivax HB Dialysis formulation: 40 mcg/mL suspension, dosing tailored for patients undergoing hemodialysis.

Specific Patient Populations:
- Patients with kidney disease or on dialysis receive higher antigen concentrations (e.g., 40 mcg/mL) to ensure adequate immune response.
- Immunocompromised adults may require additional doses or modified schedules as per clinical guidelines.
- Pregnant and breastfeeding women can receive the vaccine; pregnancy registries monitor outcomes.
- Adults with known exposure to hepatitis B virus may receive an accelerated vaccination schedule and concurrent hepatitis B immune globulin as appropriate.
- Vaccine administration should be individualized according to patient health status, immunization history, and risk factors with close adherence to local health authority recommendations.

Clinical guidelines emphasize completing the full vaccination schedule to achieve optimal and durable immunity.

Mechanism Of Action

The hepatitis B adult vaccine functions by inducing active immunity through exposure to hepatitis B virus surface antigen (HBsAg) without causing disease. It contains recombinant HBsAg proteins produced in yeast cells, or other platforms, which serve as immunogens stimulating the host's immune system. Upon intramuscular injection, the vaccine antigens are recognized and engulfed by antigen-presenting cells (APCs) such as dendritic cells and macrophages at the injection site.

Within APCs, the HBsAg is processed and presented on major histocompatibility complex (MHC) class II molecules, activating CD4+ helper T lymphocytes. These helper T cells then stimulate B cells to produce specific anti-HBs antibodies. This humoral immune response is critical for protection, as the antibodies neutralize circulating hepatitis B virus, preventing its entry into hepatocytes. The vaccine also induces a cellular immune response, generating memory T cells that contribute to long-lasting immunity.

Biochemically, the recombinant antigen mimics the natural viral surface protein epitopes, eliciting an immunological reaction without containing viral DNA, ensuring safety and the inability to cause infection. Certain formulations (e.g., Heplisav-B) contain novel adjuvants that activate specific innate immune receptors such as Toll-like receptors to enhance immunogenicity, allowing for fewer doses and quicker seroprotection. This engagement of the innate immune system provides stronger antigen presentation and a more robust adaptive response.

Clinical studies demonstrate that vaccinated individuals develop protective antibody titers (anti-HBs levels ≥10 mIU/mL) post-immunization, correlating with effective prophylaxis against hepatitis B infection. Comparative to natural infection, the vaccine induces similar antibody profiles without the risk of viral replication or liver pathology. Ongoing research aims to optimize adjuvants and dosing schedules to increase efficacy in immunocompromised populations and those with poor vaccine responsiveness.

Pharmacological Actions

Induces active immunity against hepatitis B virus by stimulating the production of protective anti-HBs antibodies.
Contains recombinant hepatitis B surface antigen (HBsAg) that mimics natural viral components to elicit immune response.
Activates antigen-presenting cells to process and present HBsAg peptides to T-helper lymphocytes.
Stimulates B cells to produce neutralizing antibodies preventing viral entry into liver cells.
Generates immunological memory through T and B lymphocyte activation for long-term protection.
Includes adjuvants in some formulations to enhance innate immune receptor engagement and antigen presentation.
Does not contain live virus and cannot cause hepatitis B infection.
Rapidly induces protective antibody levels in most healthy adults after completion of the vaccine series.
Can overcome immune tolerance in certain individuals through adjuvant-mediated enhancement of immune response.
Demonstrates immunogenicity in special populations including those with chronic kidney disease and on dialysis.
Reduces incidence and prevalence of hepatitis B infections and associated liver complications.
Does not interfere with immune responses to other concurrently administered vaccines depending on timing.
Triggers a Th1-skewed immune response promoting effective virus neutralization.
Produces minimal systemic exposure and systemic side effects due to localized immune activation.

Therapeutic Or Clinical Uses

Active immunization for the prevention of hepatitis B virus infection in adults at risk.
Pre-exposure prophylaxis in individuals with potential exposure to bodily fluids or blood containing hepatitis B virus.
Vaccination of healthcare workers to prevent occupational exposure to hepatitis B.
Immunization of patients with chronic kidney disease or those undergoing hemodialysis.
Protection of individuals with multiple sexual partners or those engaging in unsafe sexual practices.
Prevention of perinatal transmission in pregnant women vaccinated prior to or during pregnancy.
Use in individuals who use injectable drugs to reduce viral transmission through shared needles.
Immunization of persons living with hepatitis C or HIV to reduce co-infection risks.
Vaccination recommended in correctional facilities and congregate living settings to prevent outbreaks.
Post-exposure prophylaxis when combined with hepatitis B immune globulin following known exposure.
Part of routine adult immunization schedules in endemic or high-risk regions.
Protection of travelers to endemic areas who have not completed hepatitis B vaccination series.
Prevention of liver disease complications such as cirrhosis and hepatocellular carcinoma associated with hepatitis B.
Vaccination in immunocompromised patients as part of infection prevention strategy.
Use in populations with increased risk due to blood transfusions or organ transplantation.

Side Or Adverse Effects

Injection site reactions including pain, redness, swelling, or the presence of a palpable lump.
Transient headache following immunization.
Fatigue and general tiredness post-vaccination.
Mild fever may occasionally occur within a short time after vaccine administration.
Rare severe allergic reactions including anaphylaxis manifesting as hives, difficulty breathing, or swelling of face, lips, tongue, or throat.
Hypersensitivity reactions observed in persons allergic to yeast or vaccine components.
Syncope or fainting episodes sometimes reported immediately after injection, particularly in adolescents.
Local lymphadenopathy near the injection site occasionally noted.
Hypotension or dizziness following vaccination in susceptible individuals.
Rare occurrence of systemic allergic symptoms necessitating emergency treatment.
Potential for transient arthralgia or myalgia reported in post-licensure surveillance.
Insufficient data on very rare neurological events; causal association not established.
Delayed hypersensitivity responses presenting as rash or swelling can occasionally develop.
Side effects generally mild and self-limited, resolving without intervention.
Benefits of vaccination outweigh the risks of adverse effects especially given severity of hepatitis B infection.

Precautions

Use with caution in individuals with a history of severe allergic reaction to prior hepatitis B vaccine dose.
Evaluate for presence of moderate or severe acute illness prior to vaccine administration.
Inform vaccination providers about any bleeding or clotting disorders before intramuscular injection to prevent hematoma.
Assess for allergies to yeast or latex as these may predispose to hypersensitivity reactions.
Inform healthcare provider if you have a weakened immune system due to medical conditions or immunosuppressive therapy.
Monitor individuals with prior fainting history post injections to reduce risk of injury.
Pregnant or breastfeeding women should be advised about vaccine safety and benefits.
Complete the full vaccination series as incomplete vaccination may result in inadequate protection.
Maintain records of vaccination to avoid unnecessary additional doses.
Seek immediate medical advice if an allergic reaction occurs post vaccination.
Advise patients that vaccination does not protect against hepatitis A, C, D, or E or other liver diseases.
Avoid simultaneous administration with other vaccines without professional consultation.
Patients with chronic kidney disease or on hemodialysis require adjusted dosing regimens.
Report any unusual or severe side effects to healthcare providers or vaccine surveillance programs.
Use appropriate technique for intramuscular injection to enhance vaccine efficacy and safety.

Warnings

Severe allergic reactions to the first dose contraindicate receipt of further doses of the vaccine.
The risk of contracting hepatitis B infection is substantially higher and more dangerous than the potential vaccine risks.
Monitor for signs of anaphylaxis after vaccination, especially within the first 15 minutes post administration.
Inform all healthcare providers about recent vaccination as it may interfere with certain laboratory tests.
Vaccination should not be delayed in high-risk individuals due to concern for mild side effects.
Not a treatment for active hepatitis B infection; vaccination is solely preventive.
Immunization may not provide complete protection in all individuals; adherence to safety measures remains important.
Vaccination schedule deviations should be corrected promptly to ensure adequate immune protection.
Use caution in administering vaccines to immunocompromised patients; immunity may be suboptimal.
Potential hyporesponsiveness in older adults and some chronic disease patients requiring evaluation for booster doses.
Vaccine components may cause hypersensitivity in rare patient populations.
In case of accidental needle stick or exposure, vaccine should be administered as soon as possible along with immune globulin if indicated.
The vaccine is generally considered safe during pregnancy, but pregnant women should be enrolled in safety monitoring registries.
Continued surveillance for rare adverse events is recommended as with all vaccines.
Adherence to local health authority guidelines for hepatitis B immunization is paramount.

Contraindication

Known severe allergic reaction (e.g., anaphylaxis) to a previous dose of hepatitis B vaccine.
Hypersensitivity to any component of the vaccine including yeast protein.
History of life-threatening allergic reaction to vaccine excipients such as latex (if applicable).
Acute severe febrile illness at the time of scheduled vaccination (vaccination may be deferred until recovery).
Administration is contraindicated if prior vaccine led to immediate hypersensitivity events.
Use caution in patients with history of Guillain-Barré syndrome temporally related to prior vaccine doses.
Patients with progressive neurologic disorders should be evaluated prior to immunization.
Not intended for therapy of chronic hepatitis B infection or other viral hepatitis types.
Should not replace hepatitis B immune globulin in post-exposure treatment without clinical indication.
Exclusion of vaccination contraindications should be thorough in immunization campaigns.
No live virus in vaccine; hence contraindications related to live vaccines do not apply.
Patients with poorly controlled coagulopathies should be managed carefully before intramuscular injections.
Not recommended for infants or children younger than authorized age groups (use pediatric vaccines accordingly).
Contraindicated to mix with non-licensed or non-approved hepatitis B formulations.
Not a substitute for standard safety precautions in healthcare or high-risk environments.

Drug Interactions

Concomitant administration with other vaccines may alter immunogenicity; specific scheduling recommended.
Immunosuppressive therapies may inhibit adequate antibody response to the vaccine.
No known direct pharmacokinetic drug interactions due to vaccine’s protein nature and immunologic mechanism.
Certain antibiotics or antivirals do not impact the vaccine's efficacy but clinical judgment advised.
Concurrent use of hepatitis B immune globulin can complement vaccine efficacy post-exposure.
Herbal supplements or vitamins have no established interaction but should be disclosed to healthcare provider.
Live vaccines should be spaced appropriately when administered in combination with hepatitis B vaccine.
Certain chemotherapeutic agents may impair immune response and require alternate vaccination timing.
No known significant interactions with commonly prescribed medications including antipyretics and analgesics used to treat vaccine side effects.
Certain disease-modifying antirheumatic drugs (DMARDs) may reduce vaccine-induced immunity.
Immunoglobulin administration may interfere with immune response if given close to vaccination.
No interaction with hormonal contraceptives or other systemic therapies documented.
Vaccination timing may need adjustment in patients undergoing bone marrow or organ transplantation.
No evidence of interaction with antiviral prophylaxis regimens for hepatitis B treatment.
Patients should inform providers of all medications to optimize timing and response.

Preparations Of The Drug

Engerix-B: Recombinant hepatitis B vaccine available as intramuscular injectable suspension with 10 mcg/mL or 20 mcg/mL antigen concentration.
Heplisav-B: Recombinant hepatitis B vaccine with adjuvant CpG 1018, administered as 0.5 mL intramuscular injection (20 mcg antigen) in a 2-dose series.
Recombivax HB Adult: Recombinant vaccine available in adult and pediatric formulations with varying antigen concentrations, including dialysis preparations with 40 mcg/mL.
Recombivax HB Dialysis Formulation: Higher antigen concentration for use in patients on hemodialysis to enhance immunogenicity.
PreHevbrio: A 3-antigen hepatitis B vaccine formulation designed to broaden immune response coverage.
All preparations require intramuscular injection, commonly into the deltoid muscle.
Vials and prefilled syringes are available, maintaining cold chain storage between 2-8°C as per manufacturer guidelines.
Formulations may include aluminum-based adjuvants to enhance immune response.
Single-dose and multi-dose presentations exist, requiring strict aseptic technique for administration.
Preparations are sterile, non-pyrogenic, and preservative-free except multi-dose vials which may contain thimerosal.
Licensed for adult use with dosage differences noted for special populations such as pediatrics or dialysis patients.
Adjunct use with hepatitis B immune globulin is indicated in post-exposure prophylaxis scenarios.
Manufacturer instructions emphasize completing the full vaccination schedule for optimal efficacy.
Packaging includes detailed patient information leaflets and vaccination schedules.
Minimal incompatibilities with other vaccines when given at separate injection sites.