Double Dose Hepatitis B Vaccine Protects HIV-Infected Adult Patients
June 17, 2005
In the current study, investigators evaluated a double dose of hepatitis B vaccine for HIV patients in a double-blinded, randomized, controlled study with numbers for statistical validity. M.O. Fonseca and colleagues at the University Medical School of Sao Paulo noted that because HIV and hepatitis B (HBV) share many common risk factors, it is important to try to vaccinate HIV patients against HBV, and numerous reports have described a variety of variables associated with impaired response to HBV vaccines in HIV patients. Previous studies have been small, making it difficult to draw conclusions within and between them, the authors explained, so they conducted a study with more participants.
"Two hundred and ten HIV infected subjects received a standard dose (20 mcg) or a double dose (40 mcg) of recombinant hepatitis B vaccine IM 0,1 and 6 months," the investigators wrote. "Ninety-four receiving standard dose and 98 receiving double dose completed the study. The seroconversion rate (anti-HBs greater than or equal to 10/mIU/mL) was 47 and 34 percent for double dose and standard dose, respectively (p=0.07)."
"A statistically significant higher seroconversion rate was associated with double dose comparing with standard dose for patients with CD4 cell counts greater than or equal to 350 cells/mm (64.3 percent x 39.3 percent; p=0.008) but made no difference to seroconversion in those with CD4 <350 (23.8 percent x 26.3 percent; p=0.80)," the researchers found.
"Double dose also improved seroconversion comparing with standard dose for patients with HIV viral load <10,000 copies/mL (58.3 percent x 37.3 percent; p=0.01) but made no difference to seroconversion in those with HIV viral load greater than or equal to 10,000 copies/mL (16 percent x 17 percent; p=0.7)," the authors reported.
"Based on the results of this study, the best current strategy for hepatitis B vaccination in HIV patients would be to use a double dose as a primary series when the viral load is likely to be low and CD4 greater than or equal to 350, when there is likely to be an adequate immune response," the authors concluded.
The study, "Randomized Trial of Recombinant Hepatitis B Vaccine in HIV-Infected Adult Patients Comparing a Standard Dose to a Double Dose," appeared in Vaccine (2005;23(22):2902-2908).
This article was provided by CDC National Prevention Information Network. It is a part of the publication CDC HIV/Hepatitis/STD/TB Prevention News Update.