Doses Of Recombinant Hepatitis Research Articles

Hepatitis B vaccination schedules in genitourinary medicine clinics.

To compare two vaccination schedules in delivering hepatitis B vaccine to at-risk genitourinary medicine clinic attenders. Genitourinary medicine clinic of St Thomas' Hospital, London, UK. Two vaccination protocols were compared. Between January 1991 and December 1992, individuals had doses of recombinant hepatitis B vaccine at 0, 1 and 6 months (standard). From January until October 1993 doses of vaccine were administered at 0, 1 and 2 months (accelerated), following which timing of a booster dose was made on the basis of hepatitis B surface antibody (anti-HBs) assessment. Case notes were reviewed with regard to compliance rates and anti-HBs levels. Two hundred and fourteen individuals were included (standard 104, accelerated 110). Of the standard group 80.8% and 61.5% attended for the 2nd and 3rd doses respectively compared with 80.0% and 75.5% of the accelerated group (attendance for the 3rd dose chi 2 = 4.19, p < 0.05). For both of these groups compliance was significantly better in those who requested vaccination rather than being offered it opportunistically (chi 2 = 4.86, p < 0.05). Seroconversion rates were not significantly different between the two groups (87.5% versus 83.1%). A significantly higher proportion of the standard group, however, achieved anti-HBs levels greater than 100 i.u./l. Completion of hepatitis B vaccination was improved by changing to a 0, 1 and 2 month protocol. Levels of anti-HBs achieved in the accelerated group, however, were lower. If it is confirmed that maintaining anti-HBs levels is not important in retaining protection against hepatitis B then the accelerated schedule has clear advantage. If not, the advantages may be nullified by the need, in some, for an early booster.

Immune response to intramuscular revaccination after primary intradermal vaccination against hepatitis B.

We studied the immune response to (re)vaccination with three 1-mL doses of recombinant hepatitis B vaccine administered intramuscularly on days 0, 30, and 180 to 75 public safety workers (PSWs) who had not developed antibody to hepatitis B surface antigen (anti-HBs) after three intradermal doses of hepatitis B vaccine; to 45 PSWs who had initially developed antibody but did not have detectable levels 11 months after intradermal vaccination; and to 16 hepatitis B-susceptible PSWs. Levels of anti-HBs were measured on days 14 and 210 after the first intramuscular dose. Overall, 46 (61%) of 75 PSWs in the initial-nonresponse group, 43 (96%) of 45 PSWs in the lost-response group, and 5 (31%) of 16 PSWs in the new-vaccinee group had anti-HBs titers of > or = 10 mIU/mL on day 14. On day 210 (after three doses), the figures were 62 (89%) of 70 PSWs in the initial-nonresponse group, 43 (98%) of 44 PSWs in the lost-response group, and 15 (94%) of 16 PSWs in the new-vaccine group. We conclude that persons who do not seroconvert after intradermal vaccination should receive three doses of hepatitis B vaccine by the intramuscular route.

Comparative study of the immunogenicity and safety of two doses of recombinant hepatitis B vaccine in healthy adolescents

A prospective, two-armed, open-label, randomized trial was performed to compare the geometric mean titers (GMT), seroprotection (SP) and seroconversion (SC) rates found after administration of two doses of recombinant hepatitis B vaccine. Recombinant hepatitis B vaccine 10 or 20 micrograms was administered IM at 0, 1, and 6 months in healthy adolescents. Volunteers who received either dose of the vaccine had similarly high seroconversion and seroprotection rates at all visits. At Month 8, both doses of the vaccine were highly immunogenic with GMTs of 1989 mIU/mL (10 micrograms dose) and 7672 mIU/mL (20 micrograms dose) and nearly equivalent SP rates (97% and 99% in the 10 and 20 micrograms dose groups, respectively). The geometric mean titers of seroconverters at Months 3, 6 and 8 were significantly greater in the 20 micrograms group as compared to the 10 micrograms group (p < or = 0.003). Both doses were well-tolerated, with injection site pain the most common reported adverse event. Injection site pain was reported significantly (p = 0.004) more by volunteers who received the 20 micrograms dose (10.7%) compared with volunteers who received the 10 micrograms dose (3.8%). Vaccination with 10 micrograms of recombinant hepatitis B vaccine may provide a clinically effective and economical alternative to the use of the 20 micrograms dose in healthy adolescents.

Long-Term Immunogenicity and Efficacy of Hepatitis B Vaccine in Hemodialysis Patients

Although the efficacy of hepatitis B vaccines in patients under chronic hemodialysis treatment has been well documented, the persistence of immunity in this population remains largely unknown. In this study we have followed 60 hemodialysis patients up to 3 years after primary hepatitis B vaccination (four doses of recombinant hepatitis B vaccine; Engerix B, 20 mg/dose) to evaluate the persistence of immunity (as indicated by serum levels of antibody to hepatitis B surface antigen-anti-HBs-higher than or equal to 10 mIU/ml). Fourty-four (73%) patients developed anti-HBs levels above 10 mIU/ml after vaccination; the remaining 16 (27%) vaccinees were considered nonresponders and were given a booster dose that again failed to elicit an immunoresponse. After 3 years of follow-up, 18 out of 44 (41%) responders had no detectable anti-HBs levels in the serum (antibody loss occurring within 8 and 12 months in 3 cases, within 1 and 2 years in 13, and within 2 and 3 years in 2 other cases). When compared with the responders that lost their antibodies during the follow-up period, those who remained immunoreactive 3 years after vaccination was initiated were younger and had higher anti-HBs levels at 8 months of follow-up. Two hepatitis B virus infections were detected among nonresponders during the follow-up period. Based on these data, we conclude that patients undergoing chronic hemodialysis therapy not only have lower response rates to hepatitis B vaccination than healthy adults, but also that these are frequently transient.(ABSTRACT TRUNCATED AT 250 WORDS)