A common framework for the clinical development of vaccines involves the study of several candidate compounds in Phase 1 followed by the selection of potential vaccine regimens for study in Phase 2 and Phase 3. In the attached presentation, Cytel Consulting’s Jim Bolognese compares traditional and adaptive Phase 1/Phase 2 studies for vaccines and infectious diseases, providing simulations results for both 2-stage and multi-stage adaptive designs. Jim also outlines a structure for a Hybrid Adaptive Study.
In both traditional and adaptive studies for infectious diseases, a study of early bacteriocidal activity(EBA) is followed by a serial sputum colony count (SSCC) study. The difference is that while traditional trials have a fixed sample size for all regiments, in an adaptive trial there is ‘adaptive allocation’ of trial participants into the most promising regimens. Adaptive vaccine trials can take a similar structure, with a short-term study evaluating the titers of immune response, followed by a longterm efficacy study.
Jim also proposes the Hybrid Adaptive Study in which both the EBA and SSCC are tested in a single 2-part study, with adaptive allocation into promising regimens.