Chap T. Le
Distinguished Professor
University of Minnesota
Division of Biostatistics
Wednesday, September 18, 2002
3:30 PM
Moos 5-125
University of Minnesota, Minneapolis East Bank Campus
Abstract:
First vaccines are traditionally licensed after showing favorable results from
phase III efficacy trials. Subsequent competing vaccines, however, have been
licensed primarily on the basis of immunogenicity data rather than clinical
efficacy. Focusing on pneumococcal vaccines where optical densities are measured
and serum antibody concentrations are "estimated" (from a statistical
model) using an immunoglobulin (IgG) enzyme-linked immunosorbent assay (ELISA),
this talk will address on two highly related issues: the determination of an
upper limit for quality control used in the assay methodology (the maximum tolerated
limit or MTL) and the identification of vaccine responders. The goal is to form
the basis for the eventual comparison of immunogenicity results in terms of
proportions of responders.