title: Statistical issues in the design of HIV vaccine trials.
abstract: HIV vaccine trials present significant challenges related to trial endpoints, vaccine efficacy measurement, and the role of nonvaccine interventions. Infection is a valid endpoint for detecting sterilizing immunity. But if the vaccine prevents AIDS without preventing infection, infection may be a misleading surrogate. Appropriate endpoints must be defined for other mechanisms of vaccine action. Direct, indirect, behavioral, and biological effects all determine vaccine efficacy. False security among HIV-vaccine recipients may make negative behavioral effects an important component of vaccine performance. Both biological potency and a more comprehensive program effectiveness should be measured. These goals may require unblinded designs or community randomization. Nonvaccine interventions are currently the only HIV-prevention strategy. Support for larger scale implementation requires more rigorous evaluation that is less dependent on self-reported behavioral changes. The vaccine trial cohorts provide a unique opportunity to cost-effectively evaluate behavioral interventions.
authors.affiliation: Department of Biostatistics, University of Washington, Seattle 98195, USA.
authors.forename: C
authors.initials: C
authors.lastname: Schaper
authors.forename: T R
authors.initials: TR
authors.lastname: Fleming
authors.forename: S G
authors.initials: SG
authors.lastname: Self
authors.forename: W N
authors.initials: WN
authors.lastname: Rida
mesh_terms: D016915:AIDS Vaccines / Q000494:pharmacology / Q000592:standards*; D002986:Clinical Trials as Topic / Q000592:standards / Q000706:statistics & numerical data*; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D015438:Health Behavior; D006801:Humans; D012107:Research Design; D014481:United States / Q000453:epidemiology
chemical_list: D016915:AIDS Vaccines