Background: Adenoviruses are among the most promising vectors for the development of an HIV vaccine. The results of the phase IIB study of the adenovirus serotype 5-based Merck Trivalent HIV vaccine have raised the concern that serological immunity to adenovirus serotype 5 (Ad5) could be linked to HIV acquisition risk in high-risk individuals. We examined the association between adenovirus serostatus and the rate of incident HIV infection in populations at elevated risk of HIV acquisition.
Methods: We performed a nested case–control study of Ad5 serostatus among 299 HIV-infected and 590 matched HIV-uninfected persons participating in the Multicenter AIDS Cohort Study (MACS) and in HPTN 039, a study of herpes simplex virus 2 suppression among adults in the United States, South America, and Africa. Appropriate HIV cases and controls were identified in each cohort, and Ad5-neutralizing antibody titers were compared in these two groups.
Results: In MACS and HPTN 039, the relative risks of incident HIV infection among Ad5-seropositive vs. Ad5-seronegative individuals were 1.1 (95% confidence interval 0.8–1.5, P = 0.57) and 1.0 (95% confidence interval 0.4–2.3, P = 0.99), respectively. HIV-1 acquisition rates did not vary significantly by Ad5-neutralizing antibody titer.
Conclusion: The presence of Ad5-neutralizing antibodies is not linked to the risk of HIV acquisition among populations at elevated risk of HIV infection.
aVaccine and Infectious Diseases Institute, Fred Hutchinson Cancer Research Center, USA
bDepartment of Medicine, USA
cDepartment of Laboratory Medicine, USA
dDepartment of Epidemiology, USA
eDepartment of Global Health, University of Washington, Seattle, Washington, USA
fAsociación Civil Impacta Salud y Educación, Lima, Peru
gDepartment of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
hSchool of Public Health, University of California Los Angeles, Los Angeles, California, USA.
Received 11 August, 2010
Revised 18 October, 2010
Accepted 28 October, 2010
Correspondence to Marcel Curlin, MD, Department of Medicine, University of Washington, 1959 Pacific Street, Seattle, WA 98195, USA. Tel: +1 206 667 1677; fax: +1 206 667 6366; e-mail: firstname.lastname@example.org