We investigated effects of vaccination with AIDSVAX B/E HIV-1 candidate vaccine on blood and seminal plasma HIV-1 RNA viral loads (BVL and SVL, respectively) in vaccine recipients (VRs) and placebo recipients (PRs) who acquired infection.
Linear mixed models were fitted for repeated measurements of BVL. Generalized estimating equations were used to assess the difference in SVL detectability between VRs and PRs.
A total of 196 participants became HIV-1 infected during the trial. Thirty-two (16%) became infected with HIV-1 subtype B and 164 (84%) with HIV-1 subtype CRF01_AE. Per protocol-specified analysis, there were no differences in BVL levels between VRs and PRs. When stratified by HIV-1-infecting subtype, vaccination with AIDSVAX B/E was initially associated with higher BVL among HIV-1 CRF01_AE-infected VRs compared with HIV-1 CRF01_AE-infected PRs; however, this difference did not persist over time. HIV-1 subtype B-infected VRs had slightly higher BVL levels and were more likely to have detectable SVL during the follow-up period than HIV-1 subtype B-infected PRs.
Subtle differences in BVL and SVL were detected between VRs and PRs. These results may help to further understand the dynamics between HIV-1 vaccination, HIV-1-infecting subtypes, and subsequent viral expression in different body compartments.
From the *Thailand Ministry of Public Health-US Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; †National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA; ‡Fred Hutchinson Cancer Research Center and Department of Biostatistics, University of Washington, Seattle, WA; §Department of Microbiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand; ‖Bangkok Vaccine Evaluation Group, Bangkok, Thailand; ¶VaxGen Inc, South San Francisco, CA; #Vaccine Trial Center, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; and **Bangkok Metropolitan Administration, Bangkok, Thailand. Dwip Kitayaporn is now with Bumrungrad International Clinical Research Center, Bumrungrad International Hospital, Bangkok, Thailand. Timothy D. Mastro is now with Family Health International, Research Triangle Park, NC.
Received for publication June 30, 2008; accepted February 5, 2009.
The phase III efficacy trial of AIDSVAX B/E was carried out with financial support from VaxGen, Inc, South San Francisco, CA, and the Centers for Disease Control and Prevention, Atlanta, GA, as part of research collaboration with the Bangkok Metropolitan Administration, the Ministry of Public Health of Thailand, and Mahidol University, Bangkok, Thailand.
W.K. was a doctoral trainee supported by the Fogarty AIDS International Training and Research Program, grant number D43-TW00003 at the University of California, Berkeley, CA.
Conflict of interest: None of the authors have a commercial or other financial interest associated with the information presented in this article, except Dr. M.G. who is employed by and owns stock in VaxGen, Inc.
Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of US Centers for Disease Control and Prevention.
Registry's URL: http://www.clinicaltrials.gov/ct2/show/NCT00006327?term=AIDSVAX&rank=6. Trial's registration number: NCT00006327.
Correspondence to: Dr. Wanitchaya Kittikraisak, PhD, MPH, PO Box 139 Nonthaburi 11000, Thailand (e-mail: firstname.lastname@example.org).