Umanbig (Human Hepatitis B Immunoglobulin)
Passive immunization for prevention of hepatitis B virus infection
Umanbig is a human hepatitis B immunoglobulin (HBIG) used for passive immunization against the hepatitis B virus. It provides immediate, temporary protection by supplying pre-formed antibodies. Umanbig is primarily used to prevent hepatitis B reinfection after liver transplantation, for post-exposure prophylaxis, to protect newborns of carrier mothers, and to safeguard hemodialysis patients while vaccination takes effect.
Quick Facts
Key Takeaways
- Umanbig provides immediate passive immunity against hepatitis B by delivering pre-formed anti-HBs antibodies via intramuscular injection.
- It is essential for preventing hepatitis B recurrence after liver transplantation due to HBV-related liver failure, typically administered every 15 days post-transplant.
- Umanbig is critical for post-exposure prophylaxis — ideally given within 24–72 hours of accidental hepatitis B exposure in non-immunized individuals.
- Newborns of hepatitis B carrier mothers should receive Umanbig at birth alongside hepatitis B vaccination to prevent vertical transmission.
- The product must be stored refrigerated (2–8°C), protected from light, and must never be frozen. It should not be used if the solution appears cloudy or contains particles.
What Is Umanbig and What Is It Used For?
Umanbig belongs to the class of specific immunoglobulins, which are concentrated preparations of human antibodies derived from the plasma of donors with high levels of anti-hepatitis B surface antigen (anti-HBs) antibodies. Unlike active vaccination, which stimulates the body to produce its own antibodies over several weeks, Umanbig provides immediately available protection by delivering pre-formed antibodies directly into the patient's body. This mechanism is known as passive immunization.
The hepatitis B virus (HBV) is a major global health concern, affecting an estimated 296 million people chronically worldwide according to the World Health Organization (WHO). HBV is transmitted through contact with infected blood or body fluids and can cause acute hepatitis, chronic liver disease, cirrhosis, and hepatocellular carcinoma. Passive immunization with hepatitis B immunoglobulin plays a crucial role in preventing infection in high-risk situations where immediate protection is needed.
Approved Indications
Prevention of hepatitis B reinfection after liver transplantation: Patients who undergo liver transplantation due to hepatitis B-related liver failure are at high risk of graft reinfection. Umanbig is administered as part of a long-term prophylactic regimen, typically in combination with antiviral agents such as entecavir or tenofovir, to maintain adequate anti-HBs antibody levels and prevent recurrence. International guidelines from the European Association for the Study of the Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD) consider HBIG a cornerstone of post-transplant HBV prophylaxis.
Post-exposure prophylaxis in non-immunized individuals: When a person who has not been vaccinated against hepatitis B (or whose vaccination status is incomplete or unknown) is accidentally exposed to the virus — for example through a needlestick injury, mucous membrane contact, or sexual contact with an infected individual — Umanbig provides rapid protection. For optimal effectiveness, it should be administered as soon as possible after exposure, ideally within 24 to 72 hours. It is typically given alongside hepatitis B vaccination to provide both immediate and long-term immunity.
Protection for hemodialysis patients: Patients with severely impaired kidney function who require hemodialysis are at increased risk of hepatitis B infection due to frequent blood access procedures. Umanbig can provide temporary protection for these patients while hepatitis B vaccination takes effect, as the immune response to vaccination is often impaired in this population.
Prevention of mother-to-child transmission: Newborns born to mothers who are hepatitis B carriers (HBsAg-positive) are at very high risk of acquiring the infection during birth. Administering Umanbig to the newborn at birth or as soon as possible thereafter, in combination with the first dose of hepatitis B vaccine, is the standard of care worldwide. This dual approach has been shown to reduce the rate of vertical transmission by over 90% according to WHO guidelines.
Booster protection for vaccine non-responders: Some individuals fail to develop adequate antibody levels after completing the hepatitis B vaccination series. For those who remain at continuous risk of HBV infection and do not respond to repeated vaccination attempts, periodic administration of Umanbig can provide ongoing passive protection.
What Should You Know Before Taking Umanbig?
Contraindications
Umanbig must not be used if you are allergic (hypersensitive) to human immunoglobulins or to any of the other ingredients in the product (glycine, sodium chloride, water for injections). Allergic reactions to immunoglobulin preparations, while uncommon, can be severe and potentially life-threatening.
Patients with immunoglobulin A (IgA) deficiency require special consideration. These individuals may develop anti-IgA antibodies in their blood. Since Umanbig contains small amounts of IgA (up to 300 micrograms per milliliter), there is a risk of severe allergic reactions, including anaphylaxis. Your physician must carefully weigh the benefits of treatment against the potential risk of allergic reactions in this population.
There is no benefit to administering Umanbig to individuals who are already hepatitis B surface antigen (HBsAg) carriers, as the product is designed to neutralize free virus particles in non-infected or newly exposed persons.
Warnings and Precautions
Umanbig must not be injected into a blood vessel (intravenous administration). Inadvertent intravenous injection can cause acute circulatory failure (shock), which is a medical emergency. The healthcare professional administering the injection must ensure proper intramuscular placement.
Allergic and anaphylactic reactions: Although severe allergic reactions to Umanbig are rare, they can occur even in patients who have previously tolerated immunoglobulin treatment without issues. Symptoms may include a sudden drop in blood pressure, difficulty breathing, wheezing, fainting, fever, and skin reactions such as hives or widespread rash. If an allergic or anaphylactic reaction is suspected, the injection must be stopped immediately and standard emergency treatment for shock should be initiated by the healthcare provider.
Thromboembolic events: If you experience any of the following symptoms after receiving Umanbig, contact your doctor immediately or seek emergency care: difficulty breathing, chest pain, pain or swelling in arms or legs, or loss of movement or sensation in any part of the body. These may be signs of a blood clot (thromboembolism), which is a rare but serious complication associated with immunoglobulin products.
Sodium content: Umanbig contains 3.9 mg sodium per milliliter. For the 1 ml vial, this equates to approximately 0.19% of the WHO-recommended maximum daily sodium intake of 2 grams for an adult. For the 3 ml vial, the sodium content is 11.7 mg (approximately 0.58% of maximum daily intake). This should be taken into account for patients on a sodium-restricted diet, particularly when larger doses are required.
Virus safety and plasma-derived products: Because Umanbig is manufactured from human plasma, special measures are taken to prevent transmission of infections. These include careful selection and screening of blood and plasma donors, testing each donation for infectious markers, and incorporating viral inactivation and removal steps during manufacturing. These measures are considered effective against enveloped viruses such as HIV, hepatitis B virus, and hepatitis C virus, as well as against the non-enveloped hepatitis A virus. However, these measures may be of limited value against certain non-enveloped viruses such as parvovirus B19. Clinical experience with immunoglobulin products has not linked them to hepatitis A or parvovirus B19 infections, likely because the naturally present antibodies in these products provide protective effects.
Product traceability: Each time Umanbig is administered, the product name and batch number should be recorded to maintain traceability. This is a standard practice for all plasma-derived medicinal products and facilitates safety monitoring.
Effect on blood tests: After receiving Umanbig, you should inform your healthcare provider before any blood tests, as the product may interfere with certain antibody tests, particularly those assessing antibodies against red blood cells (such as the Coombs test).
Pregnancy and Breastfeeding
The safety of Umanbig during pregnancy has not been established through controlled clinical studies. Therefore, it should only be administered to pregnant women with caution and when clearly necessary. However, extensive clinical experience with immunoglobulin products in general suggests that no harmful effects on pregnancy, fetal development, or the newborn are expected. The decision to use Umanbig during pregnancy should involve a careful assessment of the potential benefits for the mother versus any theoretical risks.
The safety of Umanbig during breastfeeding has similarly not been established in controlled clinical trials. Immunoglobulins do pass into breast milk, and this may actually provide some protection to the nursing infant against pathogens that enter through mucosal surfaces. Nevertheless, caution is advised, and the decision should be made in consultation with your healthcare provider.
Clinical experience with immunoglobulins suggests no harmful effects on fertility are expected.
Driving and Operating Machinery
Umanbig has no or negligible effects on the ability to drive or operate machinery under normal circumstances. However, if you experience any side effects during or after treatment — such as dizziness, low blood pressure, or malaise — you should wait until these symptoms have fully resolved before driving or operating machinery.
Children
Umanbig can be used in children, including neonates. No special measures or additional monitoring beyond standard practice are required for pediatric patients. Dosing is adjusted based on body weight and indication, as described in the dosage section.
How Does Umanbig Interact with Other Drugs?
Drug interactions with Umanbig are primarily related to its effects on the immune response to vaccination. As a preparation of concentrated human antibodies, it can interfere with the body's ability to mount an active immune response to certain vaccines. Understanding these interactions is essential for proper scheduling of immunizations in patients who receive HBIG.
Live Attenuated Vaccines
Umanbig can impair the development of an immune response to live attenuated virus vaccines, including those for measles, mumps, rubella (MMR), and varicella (chickenpox). The pre-formed antibodies in Umanbig may neutralize the weakened vaccine virus before the body can develop its own immune response. For this reason, a minimum interval of 3 months should elapse between administration of Umanbig and vaccination with any live attenuated vaccine.
Conversely, if a live attenuated vaccine has been given recently, a period of 3 to 4 weeks should pass before Umanbig is administered, to allow the vaccine-induced immune response to develop. If Umanbig must be given within this 3–4 week window due to urgent clinical need, the live vaccine should be re-administered at least 3 months after the immunoglobulin was given.
Hepatitis B Vaccine
The hepatitis B vaccine can and should be administered concurrently with Umanbig in most clinical scenarios, particularly for post-exposure prophylaxis and neonatal immunization. This simultaneous approach provides both immediate passive protection (from the immunoglobulin) and the initiation of long-term active immunity (from the vaccine). However, the vaccine and the immunoglobulin must be injected at different anatomical sites to prevent the antibodies from neutralizing the vaccine antigen.
Other Medications
Umanbig must not be mixed with other medicinal products in the same syringe or infusion line. There are no other significant known drug-drug interactions. However, as with all immunoglobulin products, patients should inform their healthcare provider about all medications they are currently taking, have recently taken, or plan to take.
| Interacting Substance | Type | Effect | Recommendation |
|---|---|---|---|
| Live attenuated vaccines (MMR, varicella) | Major | Reduced vaccine immune response | Wait at least 3 months after HBIG before vaccinating |
| Hepatitis B vaccine | Concurrent use | No negative interaction when given at separate sites | Give simultaneously but at different injection sites |
| Other injectable medications | Physical incompatibility | Potential degradation if mixed | Do not mix in the same syringe |
| Serological blood tests (e.g., Coombs test) | Diagnostic interference | False positive results for anti-red blood cell antibodies | Inform laboratory of recent HBIG administration |
What Is the Correct Dosage of Umanbig?
Umanbig should always be used exactly as directed by your physician or pharmacist. The dosage is individualized based on the specific clinical indication, the patient's body weight, and the measured anti-HBs antibody levels. The drug is administered as an intramuscular (IM) injection. Before use, the solution should be brought to room temperature or body temperature. Once drawn into a syringe, it must be administered immediately.
For larger volumes — exceeding 2 ml in children or 5 ml in adults — the dose should be divided into multiple injections and administered at different anatomical sites to reduce local discomfort and improve absorption. The solution should be clear, colorless to pale yellow or light brown. Do not use the solution if it appears cloudy or contains visible particles.
Post-Liver Transplant Prophylaxis (Adults)
Recommended Regimen
Dose: 2,160 IU intramuscularly every 15 days following transplantation, except during the first week post-transplant.
Target antibody levels: Anti-HBs antibody levels should be maintained above 100 IU/L in HBV-DNA negative patients and above 500 IU/L in HBV-DNA positive patients.
Duration: Long-term treatment; dosage is adjusted based on regular monitoring of anti-HBs levels.
Concomitant use of appropriate antiviral agents (such as entecavir or tenofovir) should be considered as standard prophylaxis to prevent hepatitis B reinfection.
No data are currently available regarding the use of Umanbig for prevention of HBV recurrence after liver transplantation in pediatric patients. Dosing in this setting should follow specialist hepatology guidance.
Post-Exposure Prophylaxis
Accidental Exposure in Non-Immunized Individuals
Dose: At least 500 IU (international units), depending on the degree and nature of exposure.
Timing: As soon as possible after exposure, ideally within 24–72 hours.
Hepatitis B vaccination should be initiated simultaneously, with the first vaccine dose given on the same day at a different injection site.
Hemodialysis Patients
Recommended Dose
Dose: 8–12 IU/kg body weight, up to a maximum of 500 IU, every two months until vaccination becomes effective.
Regular monitoring of anti-HBs antibody levels is recommended to guide ongoing prophylaxis.
Neonates of Hepatitis B Carrier Mothers
Recommended Dose
Dose: 30–100 IU/kg body weight at birth or as soon as possible after birth.
Follow-up: Repeat doses may be required until vaccination has become effective.
The first dose of hepatitis B vaccine should be administered simultaneously at a different injection site. The combined approach of HBIG plus vaccination reduces the risk of vertical transmission by over 90%.
Vaccine Non-Responders
Ongoing Prophylaxis
Adults: 500 IU every two months.
Children: 8 IU/kg body weight every two months.
This regimen is indicated for individuals who have not developed measurable anti-HBs antibodies after vaccination and who remain at continuous risk of hepatitis B exposure.
| Indication | Patient Group | Dose | Frequency |
|---|---|---|---|
| Post-liver transplant prophylaxis | Adults | 2,160 IU IM | Every 15 days (adjusted by anti-HBs levels) |
| Post-exposure prophylaxis | Non-immunized individuals | ≥500 IU IM | Single dose within 24–72 hours |
| Hemodialysis protection | Dialysis patients | 8–12 IU/kg (max 500 IU) | Every 2 months until vaccine effective |
| Neonatal prophylaxis | Newborns of HBsAg+ mothers | 30–100 IU/kg | At birth; repeat if needed |
| Vaccine non-responders | Adults / Children | 500 IU (adults) / 8 IU/kg (children) | Every 2 months |
Overdose
The consequences of overdose with Umanbig are not well characterized. No specific antidote exists. If an overdose is suspected, supportive care should be provided, and the patient should be monitored closely for any adverse reactions. Contact your healthcare provider, hospital emergency department, or poison control center for guidance.
What Are the Side Effects of Umanbig?
Like all medicines, Umanbig can cause side effects, although not everyone experiences them. Most side effects associated with intramuscular immunoglobulin preparations are mild and self-limiting. However, some reactions can be serious and require prompt medical attention. Understanding the spectrum of possible adverse effects helps patients and caregivers recognize when to seek help.
Contact your doctor immediately or go to the nearest hospital if you experience: itching, skin rash or hives, swelling of the lips, face, or tongue, difficulty swallowing, difficulty breathing, or fainting. These may be signs of a severe allergic reaction (anaphylaxis) or anaphylactic shock, which requires emergency treatment.
The following side effects have been reported with Umanbig and with intramuscular human immunoglobulin preparations in general. Frequencies are categorized according to international convention where known, or listed as "not known" where the frequency cannot be estimated from available data.
Common Side Effects
- Injection site reactions: pain, swelling, redness (erythema), hardening (induration), warmth, rash, itching
Uncommon Side Effects
- Chills
- Headache
- Dizziness
- Fever
- Nausea
- Vomiting
- Joint pain (arthralgia)
- Low blood pressure (hypotension)
- Moderate lower back pain
- Allergic skin reactions
Rare Side Effects
- Sudden drop in blood pressure (severe hypotension)
- Anaphylactic shock (severe life-threatening allergic reaction)
Frequency Not Known
- Headache
- Increased heart rate (tachycardia)
- Low blood pressure (hypotension)
- Nausea and vomiting
- Skin reactions, redness (erythema), itching
- Joint pain (arthralgia)
- Fever
- Malaise (general feeling of illness)
- Chills
Side Effects in Children
The frequency, type, and severity of side effects observed in children are expected to be the same as those seen in adults. No additional or unique pediatric side effects have been identified. As with adults, injection site reactions are the most commonly reported adverse effect in children, and these are typically mild and resolve without treatment.
Reporting Side Effects
If you experience any side effects, including those not listed above, report them to your healthcare provider. You can also report suspected adverse reactions directly to your national pharmacovigilance authority. In the United States, side effects can be reported to the FDA MedWatch program. In the European Union, reports can be submitted through the national competent authority of each member state. In the United Kingdom, reporting is done through the Yellow Card scheme operated by the MHRA. Reporting helps improve the safety information available for medicines.
How Should You Store Umanbig?
Proper storage of Umanbig is critical to maintaining the effectiveness and safety of this biological product. As a plasma-derived immunoglobulin, it is sensitive to temperature, light, and freezing, all of which can degrade the active antibodies and compromise the product's protective efficacy.
- Temperature: Store in a refrigerator at 2°C to 8°C (36°F to 46°F).
- Light protection: Keep the vial in its original outer carton to protect it from light at all times.
- Do not freeze: Freezing can damage the immunoglobulin proteins and render the product ineffective. If the product has been accidentally frozen, it must not be used.
- Shelf life: Do not use Umanbig after the expiry date printed on the carton (EXP). The expiry date refers to the last day of the stated month.
- Visual inspection: Before use, visually inspect the solution. It should be clear and colorless, or pale yellow to light brown. During storage, the solution may become slightly opalescent or form small amounts of particulate matter. However, do not use the solution if it is markedly cloudy or contains visible particles at the time of use.
- After opening: Once drawn into a syringe, the solution must be administered immediately. Do not store opened or partially used vials for later use.
Keep Umanbig out of the sight and reach of children. Unused product and waste materials should be disposed of in accordance with local regulations for biological waste. Do not dispose of medicines via wastewater or household waste — consult your pharmacist for proper disposal methods.
What Does Umanbig Contain?
Understanding the composition of Umanbig helps patients and healthcare professionals make informed decisions about its use, particularly regarding potential allergies or sensitivities to any of the ingredients.
Active Ingredient
The active substance is human hepatitis B immunoglobulin, a concentrated preparation of antibodies (immunoglobulins) purified from the pooled plasma of human donors who have high levels of antibodies against the hepatitis B surface antigen (anti-HBs). The product contains 100–180 g/L of total human protein, of which at least 90% is immunoglobulin G (IgG).
| Component | 180 IU / 1 ml Vial | 540 IU / 3 ml Vial |
|---|---|---|
| Human protein | 100–180 g/L | 100–180 g/L |
| IgG content (minimum) | ≥90% | ≥90% |
| Anti-HBs antibodies (minimum) | 180 IU per vial (180 IU/ml) | 540 IU per vial (180 IU/ml) |
| Maximum IgA content | ≤300 μg/ml | ≤300 μg/ml |
IgG Subclass Distribution
The distribution of IgG subclasses in Umanbig reflects the natural distribution found in human plasma:
- IgG1: 63.7%
- IgG2: 31.8%
- IgG3: 3.3%
- IgG4: 1.2%
Inactive Ingredients (Excipients)
- Glycine — an amino acid used as a stabilizer to protect the immunoglobulin proteins
- Sodium chloride — to maintain physiological osmolarity
- Water for injections — the solvent
Appearance and Packaging
Umanbig is a clear solution that is colorless or pale yellow to light brown. It is available in two presentations:
- Umanbig 180 IU: Glass vial containing 1 ml of solution (180 IU total)
- Umanbig 540 IU: Glass vial containing 3 ml of solution (540 IU total)
The marketing authorization holder is Kedrion S.p.A., Loc. Ai Conti, 55051 Castelvecchio Pascoli, Barga (Lucca), Italy. The product is manufactured by Kedrion S.p.A. in S. Antimo (Naples), Italy, and is authorized in multiple European countries under the name Uman Big or Umanbig.
Frequently Asked Questions About Umanbig
Umanbig provides passive immunization — it delivers pre-formed antibodies that offer immediate but temporary protection against hepatitis B. The hepatitis B vaccine, in contrast, provides active immunization by stimulating your immune system to produce its own antibodies, which takes several weeks to develop but provides long-lasting protection. In many clinical situations, both are given simultaneously: Umanbig for immediate protection and the vaccine for long-term immunity.
Umanbig begins working almost immediately after injection, as it provides ready-made antibodies. Protective levels of anti-HBs antibodies are typically detectable in the blood within hours of intramuscular administration. Peak serum levels are usually reached within 2 to 7 days. However, the protection is temporary and wanes over weeks to months as the antibodies are naturally metabolized by the body.
Yes, in certain circumstances. Umanbig may be administered to individuals who have been vaccinated but failed to develop adequate antibody levels (vaccine non-responders), or to those whose vaccination history is incomplete or uncertain and who face an urgent exposure risk. Additionally, post-transplant patients receive Umanbig regardless of prior vaccination status, as the transplanted liver requires protection from circulating virus.
Yes, Umanbig is routinely used in newborns born to hepatitis B carrier mothers. This is a well-established practice recommended by the WHO and all major health authorities worldwide. The dose is carefully adjusted based on the newborn's body weight (30–100 IU/kg). When combined with the hepatitis B vaccine given at birth, this approach prevents over 90% of mother-to-child transmissions of hepatitis B virus.
The protection provided by Umanbig is temporary, typically lasting several weeks to a few months depending on the dose administered and the individual's metabolism. Anti-HBs antibody levels gradually decline as the body naturally breaks down the immunoglobulin. This is why repeat dosing is required for ongoing prophylaxis (e.g., post-transplant patients, hemodialysis patients). For post-exposure prophylaxis, a single dose is often sufficient when combined with vaccination, as the vaccine will provide long-term protection once the immune response develops.
No. Umanbig contains antibodies against hepatitis B — it does not contain the virus itself. The manufacturing process includes rigorous donor screening, testing for viral markers, and specific viral inactivation and removal steps. Immunoglobulin products have not been linked to transmission of hepatitis B. The anti-HBs antibodies in Umanbig actually neutralize the hepatitis B virus, providing protection against infection.
References
- World Health Organization (WHO). Hepatitis B vaccines: WHO position paper — July 2017. Weekly Epidemiological Record. 2017;92(27):369–392.
- European Association for the Study of the Liver (EASL). EASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection. Journal of Hepatology. 2017;67(2):370–398.
- Terrault NA, Lok ASF, McMahon BJ, et al. Update on prevention, diagnosis, and treatment of chronic hepatitis B: AASLD 2018 hepatitis B guidance. Hepatology. 2018;67(4):1560–1599.
- European Medicines Agency (EMA). Umanbig — Summary of Product Characteristics. Available at: ema.europa.eu.
- Schillie S, Vellozzi C, Reingold A, et al. Prevention of hepatitis B virus infection in the United States: Recommendations of the Advisory Committee on Immunization Practices. MMWR Recomm Rep. 2018;67(1):1–31.
- Cholongitas E, Papatheodoridis GV. High genetic barrier nucleos(t)ide analogue(s) for prophylaxis from hepatitis B virus recurrence after liver transplantation: a systematic review. Am J Transplant. 2013;13(2):353–362.
- World Health Organization (WHO). Global hepatitis report 2024. Geneva: World Health Organization; 2024.
- Loomba R, Liang TJ. Hepatitis B reactivation associated with immune suppressive and biological modifier therapies: current concepts, management strategies, and future directions. Gastroenterology. 2017;152(6):1297–1309.
Editorial Team
Written by the iMedic Medical Editorial Team — specialists in clinical pharmacology, hepatology, and infectious disease with documented academic background and clinical experience.
All content reviewed by the iMedic Medical Review Board following EASL, AASLD, and WHO guidelines. Evidence graded using the GRADE framework.
This article is based on Level 1A evidence from systematic reviews, meta-analyses, and international clinical practice guidelines. No commercial funding or pharmaceutical sponsorship. Read our editorial standards.