E. Santagostino et al., ACCELERATED SCHEDULE OF HEPATITIS-B VACCINATION IN PATIENTS WITH HEMOPHILIA, Journal of medical virology, 41(2), 1993, pp. 95-98
Early development of immunity after hepatitis B vaccination is particu
larly important for patients such as hemophiliacs, at high risk for ac
quiring hepatitis B from potentially infectious plasma-derived concent
rates. The purpose of this study was to evaluate whether or not protec
tive antibody titers could be achieved quickly and maintained in hemop
hiliacs by an accelerated vaccination schedule. A yeast-recombinant he
patitis B vaccine (Engerix B, SKF Ritt) was given subcutaneously in th
e deltoid region and repeated 2 and 6 weeks later to 85 hemophiliacs n
egative for hepatitis B virus (HBV) markers. After the first 22 patien
ts had been enrolled, a modification of the schedule involving a fourt
h booster dose 24 weeks after the first dose of vaccine was applied to
the next 63 consecutive vaccinees. Fifty-three percent of vaccinees h
ad antibody titers to hepatitis B surface antigen (anti-HBs greater-th
an-or-equal-to 10 mIU/ml) by week 6, even though the mean titers of an
ti-HBs were somewhat lower than those achieved historically in normal
individuals. The protection rate had increased to 87% by week 10, one
month after the third dose of vaccine, and to 93% by week 24. One year
after starting vaccination, the rate for the vaccinees who did not re
ceive the fourth booster dose was 71%, and 96% for those who did recei
ve the fourth dose, with only 2 patients not responding despite the bo
oster dose. It is concluded that even though the accelerated schedule
of immunization produced rapidly high rates of protective antibody tit
ers, a booster dose is required to obtain higher titers and provide mo
re persistent immunity. (C) 1993 Wiley-Liss, Inc.