Challenge: Diteba's main objective of this study was to develop a simple, reliable and reproducible in vitro quality control method that could be used to discriminate variation in release characteristics of NNRTI solid dose formulations to assure batch-to-batch uniformity. Diteba's scientists attempted to develop a methodology that could be used to discriminate formulation changes, and evaluate the precision, reproducibility and sensitivity for in vitro release rate study (IVRT) experiments.