During drug development, in vitro dissolution testing is an important tool for evaluating candidate formulations, designing methods for establishment of in vitro-in vivo correlations (IVIVCs), and defining specifications around manufacturing properties when scaling production. Years ago, Simulations Plus released one of the first mechanistic simulations of the in vitro dissolution test, DDDPlus™, to help groups reduce the number of ‘cut and try’ experiments to achieve their dissolution goals and improve in vitro / in vivo extrapolation (IVIVE) with the GastroPlus™ physiologically-based pharmacokinetic (PBPK) modeling software. In this webinar, case studies will be presented highlighting the use of DDDPlus and GastroPlus to optimize formulations and apply virtual ‘lot-to-lot’ variability effects to help establish dissolution specifications.