The purpose of this study is to determine whether protective anti-HB serum levels are maintained after 6 months of uninterrupted treatment with IGIV-HB Grifols, a new specific hepatitis B immune globulin, in patients having previously undergone liver transplantation.

Inclusion Criteria:

1. Patients having undergone a liver transplantation due to liver disease associated with hepatitis B virus, at least 1 year before and no more than 5 years before inclusion in the study.
2. Patients who have required treatment with HBIG, or are receiving it at present.
3. Patients from 18 to 70 years of age.
4. The patient agrees to participate and comply with all aspects of the protocol, including the planned blood sample collection, and has signed the informed consent form.

Exclusion Criteria:

1. Presence of HBV DNA or HBeAg indicating virus replication.
2. Patients with known allergies to some component of HB-IVIG, such as sorbitol (e.g. patients presenting intolerance to fructose).
3. Patients with a known background of severe or frequent reactions to products derived from plasma.
4. Patients presenting arterial hypertension that is not clinically controlled.
5. Patients presenting a creatinine value >2 mg/dl, nephrotic syndrome or renal failure.
6. Patients presenting anaemia (haemoglobin < 11 g/dl).
7. Patients being treated with interferon.
8. The patient suffers some acute or chronic medical condition that the investigator believes may interfere with the development or interpretation of the study.
9. The patient is known to abuse of alcohol, opiates, psychotropic agents or other drugs or chemical substances; or has done so in the past 12 months.
10. Pregnant women at the time of inclusion or that may be pregnant in the next 7 months or breast-feeding women.
11. Patients participating in another clinical study, or who have received another investigational product in the last 3 months.
12. Possibility that the patient may be treated with other products containing immunoglobulins in a period of 7 months.
13. Suspicion of conditions that may affect the patient's compliance, including an expected survival of less than 1 year.
14. Any patient that does not have a frozen serum sample previous to the first study medication infusion.
15. Patients with selective IgA deficiency.