title: Surrogates of protection in repeated low-dose challenge experiments.
abstract: A critical step toward developing a successful vaccine to control the human immunodeficiency virus pandemic entails evaluation of vaccine candidates in non-human primates (NHPs). Historically, these studies have usually entailed challenges (i.e., exposures) with very high doses of a simian version of human immunodeficiency virus, resulting in infection of all NHPs in the experiment after a single challenge. More recently, researchers have begun to conduct repeated low-dose challenge (RLC) studies in NHPs that are believed to more closely mimic typical exposure in natural human transmission settings. One objective of RLC studies is to assess whether measured immune responses to vaccination can serve as surrogate endpoints for the primary endpoint of interest, namely infection. In this paper, different designs of RLC studies for assessing a binary surrogate of protection are considered.
authors: Department of Biostatistics, West Virginia University, Morgantown, WV, U.S.A.
authors: Dustin M
authors: DM
authors: Long
authors: Michael G
authors: MG
authors: Hudgens
authors: Chih-Da
authors: CD
authors: Wu
mesh_terms: D016915:AIDS Vaccines / Q000008:administration & dosage* / Q000276:immunology; D000818:Animals; D016010:Binomial Distribution; D003198:Computer Simulation; D018592:Cross-Over Studies; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical / Q000379:methods; D015658:HIV Infections / Q000276:immunology* / Q000517:prevention & control; D006801:Humans; D016013:Likelihood Functions; D011323:Primates / Q000276:immunology* / Q000821:virology; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000517:prevention & control; D015302:Simian Immunodeficiency Virus / Q000276:immunology* / Q000472:pathogenicity
chemical_list: D016915:AIDS Vaccines
keywords: HIV; causal inference; immunogenicity; infectious diseases; transmission probability; vaccine
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