Granulocyte macrophage colony-stimulating factor as an adjuvant for hepatitis B vaccination of healthy adults

Granulocyte macrophage colony-stimulating factor (GM-CF) has shown promise as an adjuvant to improve the kinetics and magnitude of the immune response after vaccination. It was hypothesized that GM-CSF given intramuscularly ( IM) with hepatitis B vaccine would result in increased seroconversion rates and antibody titers, In total, 108 healthy volunteers (18-45 years old) re ceived recombinant hepatitis B vaccine IM at 0, 1, and 6 months and were ra ndomized to receive either concurrent GM-CSF (80 or 250 pg) or placebo IM w ith the first two vaccinations. The percentages of subjects achieving a pro tective level of antibody at day 56 were 58.3%, 58.8%, and 58.3% in the pla cebo and 80- and 250-mu g GM-CSF arms, respectively. The geometric mean tit ers of antibody measured on days 28, 56, and 189 were not statistically dif ferent between arms. GM-CSF given immediately before recombinant hepatitis B vaccination was safe and well tolerated but did not appear to provide sig nificant adjuvant activity at this dose.