Venbig: Uses, Dosage & Side Effects

What Is Venbig and What Is It Used For?

Venbig contains human hepatitis B immunoglobulin as its active substance. This is a highly purified preparation of immunoglobulin G (IgG) antibodies derived from pooled human plasma collected from donors who have high titres (concentrations) of antibodies against hepatitis B surface antigen (anti-HBs). These antibodies are capable of recognizing and neutralizing the hepatitis B virus, providing what is known as passive immunity – immediate protection that does not require the recipient’s own immune system to mount an active immune response.

The concept of passive immunization is fundamentally different from active vaccination. When a person receives a hepatitis B vaccine, their immune system is stimulated to produce its own antibodies over a period of weeks to months. In contrast, Venbig delivers pre-formed antibodies that are immediately active in the recipient’s circulation, providing instant protective levels of anti-HBs. This makes Venbig invaluable in situations where immediate protection is needed and there is not enough time to wait for the body’s own immune response to develop.

The hepatitis B virus (HBV) is a serious global health concern. According to the World Health Organization (WHO), an estimated 254 million people worldwide are living with chronic hepatitis B infection, which can lead to chronic liver disease, cirrhosis, hepatocellular carcinoma (liver cancer), and liver failure. While vaccination remains the cornerstone of hepatitis B prevention, specific immunoglobulins like Venbig play a critical complementary role in certain high-risk clinical scenarios.

Venbig is approved for use in the following clinical indications:

• Prevention of hepatitis B reinfection after liver transplantation: When a patient undergoes liver transplantation because of liver failure caused by hepatitis B, the new transplanted liver is at very high risk of becoming infected by any remaining circulating HBV in the recipient’s body. Without prophylaxis, reinfection rates historically exceeded 80%. Venbig, in combination with antiviral medications (such as entecavir or tenofovir), is a cornerstone of post-transplant HBV prophylaxis. The anti-HBs antibodies in Venbig neutralize circulating virus particles and prevent them from establishing infection in the new liver. This combination approach has reduced reinfection rates to below 5% in most centers.
• Post-exposure prophylaxis in non-vaccinated individuals: If a person who has not been vaccinated against hepatitis B is accidentally exposed to HBV-contaminated blood or body fluids (for example, through a needlestick injury, mucous membrane splash, or sexual contact with an infected person), Venbig can provide immediate protection. To be most effective, it should be administered as soon as possible – ideally within 24 hours and no later than 72 hours after exposure. This is typically given alongside the first dose of the hepatitis B vaccine to provide both immediate (passive) and long-term (active) immunity.
• Hemodialysis patients: Patients undergoing hemodialysis (dialysis for kidney failure) are at increased risk of HBV exposure due to the frequent blood access procedures involved. Their immune response to hepatitis B vaccination may also be impaired. Venbig can provide interim protection while vaccination takes effect, or for those who fail to mount an adequate immune response to the vaccine.
• Newborns of HBV-carrier mothers: Infants born to mothers who are positive for hepatitis B surface antigen (HBsAg) are at very high risk of acquiring HBV infection during birth. Without intervention, vertical (mother-to-child) transmission occurs in up to 90% of cases when the mother is also HBeAg-positive. Venbig is administered to these newborns shortly after birth, along with the first dose of hepatitis B vaccine, to prevent perinatal transmission. This combined approach is approximately 85–95% effective in preventing chronic HBV infection in the infant.
• Non-responders to hepatitis B vaccination: A small percentage of individuals do not produce adequate levels of anti-HBs antibodies even after a complete course of hepatitis B vaccination (these individuals are termed “non-responders”). For non-responders who remain at ongoing risk of HBV exposure, periodic administration of Venbig can provide continued passive protection.

Venbig is manufactured from human plasma by Kedrion S.p.A. in Italy. The plasma undergoes extensive processing and viral inactivation steps to ensure the safety and purity of the final product. The manufacturing process includes cold ethanol fractionation, followed by additional purification and dedicated viral inactivation/removal steps to minimize the theoretical risk of transmission of blood-borne pathogens.

What Should You Know Before Receiving Venbig?

Contraindications

There are specific situations in which Venbig must not be used. Understanding these absolute contraindications is essential before treatment begins.

• Hypersensitivity: Do not receive Venbig if you are allergic to human immunoglobulins or any of the other ingredients in the product (sucrose, sodium chloride, water for injection). Severe allergic reactions, including anaphylaxis, can occur in sensitized individuals.
• Anti-IgA antibodies: Patients who have selective IgA deficiency and have developed antibodies against IgA (anti-IgA antibodies) are at particular risk of severe anaphylactic reactions when receiving immunoglobulin preparations, even those with very low IgA content. Although Venbig contains very low levels of IgA (maximum 0.05 mg/ml), this contraindication must be carefully evaluated.

Warnings and Precautions

Before and during treatment with Venbig, inform your doctor if any of the following apply to you:

• Hypersensitivity reactions: True hypersensitivity reactions are rare but can occur even in patients who have previously tolerated immunoglobulin preparations. Signs of a severe allergic reaction include sudden drop in blood pressure, difficulty breathing, wheezing, hives, facial swelling, rapid heartbeat, or feeling faint. If any of these occur during infusion, the infusion must be stopped immediately and appropriate emergency treatment initiated. Venbig should be administered in a setting where resuscitation equipment is readily available.
• IgA deficiency: Patients with partial or complete IgA deficiency may develop anti-IgA antibodies and experience anaphylactic reactions when receiving blood products containing IgA, including immunoglobulins. Your doctor may test for anti-IgA antibodies before prescribing Venbig if IgA deficiency is suspected.
• Renal impairment: Venbig contains sucrose as an excipient. Sucrose-containing intravenous immunoglobulin products have been associated with renal dysfunction, acute renal failure, osmotic nephrosis, and even death. Patients at higher risk include those with pre-existing renal insufficiency, diabetes mellitus, elderly patients (over 65 years), patients with hypovolemia (dehydration), and those receiving nephrotoxic medications concurrently. In at-risk patients, Venbig should be infused at the minimum practicable rate, and renal function should be monitored before and during treatment.
• Transfusion-related acute lung injury (TRALI): This is a rare but potentially life-threatening complication that can occur with blood products, including immunoglobulins. TRALI is characterized by severe respiratory distress, pulmonary edema, and hypoxemia within 6 hours of transfusion. If TRALI is suspected, the infusion must be stopped and supportive care initiated immediately.
• Hemolysis: Immunoglobulin products can contain antibodies against blood group antigens (such as anti-A and anti-B), which may act as hemolysins and cause coating of red blood cells with immunoglobulin. This can result in a positive direct antiglobulin test (Coombs test) and, in rare cases, clinically significant hemolysis (breakdown of red blood cells) leading to hemolytic anemia. Patients should be monitored for signs of hemolysis, particularly if large doses are administered.
• Interference with serological testing: After receiving Venbig, the passively transferred antibodies may transiently interfere with the results of serological tests, including blood group serology (Coombs test). This is important to communicate to any healthcare provider performing blood tests during or shortly after Venbig treatment.
• Virus safety: Venbig is manufactured from human plasma. Standard measures are taken to prevent infections resulting from the use of blood-derived products, including careful selection of donors, testing of individual donations and plasma pools for specific markers of infection, and the inclusion of effective manufacturing steps for the inactivation/removal of viruses. Despite these precautions, the possibility of transmitting infectious agents cannot be completely excluded. This also applies to unknown or emerging viruses and other pathogens. The measures taken are considered effective for enveloped viruses such as HIV, HBV, and HCV, and for the non-enveloped virus HAV. The measures may be of limited value against non-enveloped viruses such as parvovirus B19.
• Cardiovascular risk factors: Because of the association between intravenous immunoglobulins and thromboembolic events, patients with pre-existing cardiovascular risk factors should be identified before treatment. These patients should receive the infusion at the lowest practicable rate and be adequately hydrated before administration.
• Sodium content: Venbig contains sodium. The 500 IU vial (10 ml solvent) contains approximately 39 mg of sodium, and the 2500 IU vial (45 ml solvent) contains approximately 175.5 mg of sodium. This should be taken into consideration for patients on a controlled sodium diet.

Your doctor will perform appropriate assessments before and during Venbig treatment to minimize the risk of these complications. Vital signs will be monitored during the infusion, and you will be observed for a period after each infusion is completed.

Pregnancy and Breastfeeding

No controlled clinical trials have been conducted with Venbig in pregnant women. However, there is extensive clinical experience with the use of intravenous immunoglobulins (IVIg) during pregnancy, and this accumulated experience suggests no harmful effects on the course of pregnancy, the fetus, or the newborn.

Immunoglobulin G (IgG) antibodies cross the placenta, particularly during the third trimester, when transplacental transfer increases progressively. This natural process provides passive immunity to the fetus and newborn infant, which is generally considered beneficial. When Venbig is administered during pregnancy, the anti-HBs antibodies may similarly cross the placenta and provide some passive protection to the unborn child against hepatitis B.

Anti-HBs antibodies may also pass into breast milk. This transfer of antibodies through breastfeeding may contribute to passive protection of the breastfed infant against hepatitis B, which is generally considered a positive effect rather than a safety concern.

Based on the available evidence, no effects on fertility are expected from the use of human immunoglobulins such as Venbig. Nevertheless, as with any medication, Venbig should be used during pregnancy and breastfeeding only when clearly needed and after careful consideration of the benefits and risks by the treating physician.

Driving and Operating Machinery

Venbig may have minor effects on the ability to drive and use machines. Some patients may experience side effects such as dizziness or low blood pressure during or shortly after infusion. If you experience any such symptoms, do not drive or operate machinery until they have resolved. Discuss with your doctor if you have concerns about performing these activities after treatment.

How Does Venbig Interact with Other Drugs?

Drug interactions with Venbig are primarily related to its effect on the immune response to live attenuated vaccines and to potential incompatibilities when mixed with other infusion solutions. It is important to inform your doctor about all medications you are taking, including vaccines you have recently received or plan to receive.

Major Interactions

Additional Interaction Considerations

The interaction between Venbig and live attenuated vaccines is a class effect of all immunoglobulin products. The passively transferred antibodies can neutralize the live vaccine virus before the recipient’s immune system has a chance to mount an appropriate response. This does not apply to inactivated vaccines, including the hepatitis B vaccine itself, which can be safely given at the same time as Venbig (administered at a different injection site).

What Is the Correct Dosage of Venbig?

Venbig dosing is highly individualized based on the clinical indication, the patient’s body weight, and the target anti-HBs antibody levels. Treatment is always prescribed and supervised by a physician experienced in the management of hepatitis B. The dosage regimens below represent general guidelines; your doctor will determine the optimal dose for your specific situation.

Prevention of HBV Reinfection After Liver Transplantation

Post-Exposure Prophylaxis

Hemodialysis Patients

Newborns of HBV-Carrier Mothers

Non-Responders to Hepatitis B Vaccination

How Venbig Is Given

Venbig is supplied as a lyophilized (freeze-dried) powder in a glass vial, accompanied by a separate vial of solvent (water for injection) for reconstitution. Before administration, the powder must be dissolved in the supplied solvent according to the manufacturer’s instructions. The reconstituted solution should be clear or slightly opalescent and free of visible particles. Do not use the solution if it appears cloudy, contains precipitate, or shows any particulate matter.

The reconstituted solution should be brought to approximately room temperature or body temperature before infusion. After reconstitution, the product should be used immediately and any unused solution should be discarded.

Venbig must be administered intravenously (into a vein). It must not be mixed with other medicinal products. A separate infusion line should be used, or the line should be flushed with physiological saline solution before and after Venbig infusion.

• Initial infusion rate: 0.46–0.92 ml/kg/h for the first 20–30 minutes. This slow initial rate minimizes the risk of infusion-related reactions.
• If well tolerated: The rate may be gradually increased up to a maximum of 1.85 ml/kg/h for the remainder of the infusion.
• At-risk patients: In patients with cardiovascular risk factors, renal impairment, or a history of infusion reactions, the minimum practicable infusion rate should be maintained throughout.

What Are the Side Effects of Venbig?

Like all medicines, Venbig can cause side effects, although not everyone experiences them. The side effects listed below are based on clinical trial data, post-marketing surveillance reports, and the known class effects of intravenous immunoglobulin products. Your medical team will monitor you during and after each infusion to detect and manage any adverse reactions promptly.

Infusion-Related Reactions

Many of the side effects associated with Venbig are related to the infusion process itself. These reactions are more common when treatment is initiated for the first time, when switching from a different immunoglobulin product, or after a long interval between treatments. The risk of infusion-related reactions can often be minimized by adhering to the recommended infusion rate, starting slowly and increasing gradually only if the infusion is well tolerated.

Side Effects by Frequency

Post-Marketing Reports

The following additional side effects have been identified through post-marketing surveillance and spontaneous reporting. Because these reports come from a population of uncertain size, it is not always possible to reliably estimate their frequency:

• Tachycardia (rapid heartbeat)
• Erythema (skin redness)
• Pruritus (itching)
• Malaise (general feeling of unwellness)
• Transient skin reactions (rash, flushing)

If you experience any side effects, including those not listed here, tell your doctor or nurse. You can also report suspected side effects to your national pharmacovigilance authority (e.g., the EMA in Europe, the FDA MedWatch program in the United States, or the MHRA Yellow Card Scheme in the United Kingdom) to help monitor the ongoing benefit-risk profile of Venbig.

How Should Venbig Be Stored?

Keep this medicine out of the sight and reach of children. Do not use after the expiry date stated on the vial label and outer carton after EXP. The expiry date refers to the last day of that month.

• Unopened product: Store below 25°C (77°F). Do not freeze.
• Light protection: Keep the vial in the outer carton to protect from light.
• After reconstitution: Use immediately. Do not store the reconstituted solution. Any unused portion must be discarded.
• Inspection: The reconstituted solution should be clear or slightly opalescent. Do not use if the solution is cloudy, turbid, or contains visible particles or precipitate.
• Temperature of administration: The reconstituted solution should be brought to approximately room temperature or body temperature before infusion to improve tolerability.

As Venbig is prepared and administered in a hospital or clinic, storage will be handled by your healthcare team and pharmacy. Do not dispose of any medicines via wastewater or household waste. The doctor or nurse will ensure proper disposal of unused medicine to protect the environment.

What Does Venbig Contain?

Active Substance

The active substance is human hepatitis B immunoglobulin (anti-HBs). After reconstitution, each milliliter of solution contains at least 50 IU of anti-HBs antibodies. The total human protein content is 50 g/L (5 g per 100 ml), of which at least 95% is immunoglobulin G (IgG).

IgG Subclass Distribution

The IgG in Venbig reflects the normal distribution of IgG subclasses found in human plasma:

The maximum IgA content is 0.05 mg/ml, which is an important specification for patients with IgA deficiency who may have anti-IgA antibodies.

Inactive Ingredients (Excipients)

• Sucrose: Used as a stabilizer. The sucrose content is up to 92 mg/ml. Patients with diabetes mellitus or renal impairment should be aware of the sucrose content, as sucrose-containing immunoglobulin products have been associated with renal dysfunction in susceptible individuals.
• Sodium chloride: Used to maintain isotonicity of the solution.
• Water for injection: Supplied as a separate vial of solvent for reconstitution.

Sodium Content

Venbig contains sodium, which should be considered for patients on a sodium-restricted diet:

• 500 IU vial (reconstituted with 10 ml solvent): Contains approximately 39 mg of sodium, equivalent to approximately 2% of the WHO-recommended maximum daily intake of 2 g for an adult.
• 2500 IU vial (reconstituted with 45 ml solvent): Contains approximately 175.5 mg of sodium, equivalent to approximately 8.8% of the WHO-recommended maximum daily intake.

Available Presentations

• 500 IU: One vial of lyophilized powder + one vial of 10 ml water for injection (solvent).
• 2500 IU: One vial of lyophilized powder + one vial of 45 ml water for injection (solvent).

Manufacturer

Venbig is manufactured by Kedrion S.p.A., based in Barga (Lucca), Italy. Kedrion is a biopharmaceutical company specializing in the development, production, and distribution of plasma-derived products.