Pn. Goldwater, RANDOMIZED COMPARATIVE TRIAL OF INTERFERON-ALPHA VERSUS PLACEBO IN HEPATITIS-B VACCINE NONRESPONDERS AND HYPORESPONDERS, Vaccine, 12(5), 1994, pp. 410-414
Adults who had received 4 x 20 mu g doses of hepatitis B (Engerix-B) v
accine (appropriately administered) and who had failed to develop dete
ctable anti-HBs or who had had a minimal response (<10 IU l(-1)) were
randomized to receive either a fifth dose of Engerix-B (20 mu g) plus
1 million units of interferon-alpha or a fifth dose of vaccine plus sa
line placebo intramuscularly (deltoid). Both vaccine and test material
were given together in one syringe and participants were blind as to
the syringe contents. Anti-HBs was tested (by enzyme immunoassay) one
to three months following the injection. Anti-HBs results from the 150
non-responders (NR) and the 26 hyporesponders (HR) are reported. Of N
Rs receiving a fifth dose plus placebo, 41% developed anti-HBs, whilst
53% of those receiving interferon-alpha developed anti-HBs. The respo
nse rates did not differ significantly. Of HRs receiving vaccine plus
placebo, 70% showed an increase in their anti-HBs titre, while 87.5% o
f those receiving interferon-alpha with vaccine had titre rises. Vacci
nee groups were well matched for age, sex and body mass index and the
interval between injection and venepuncture. Side-effects from interfe
ron-alpha were of short duration and were tolerated by vaccinees seeki
ng protection from hepatitis B infection. On the basis of this study,
a fifth dose of vaccine in non- and hyporesponsive vaccinees is recomm
ended. Interferon-alpha was of unproven value but it may increase the
likelihood of seroconversion in NRs and its use could be considered in
subjects at continued high risk of contracting hepatitis B. Anti-HBs
responses were measurably higher in interferon-alpha recipients than i
n placebo recipients.