Development and optimization of lyophilized orally disintegrating tablets using factorial design

The aim of this study was to evaluate the use of maltodextrin as a sugar-matrix former along with several cellulosic binders in the preparation of freeze-dried orally disintegrating tablets (ODT). The ODT was prepared by freeze-drying an aqueous dispersion of nimesulide (NM) containing maltodextrin and a cellulosic binder. The influence of formulation parameters on the in vitro/in vivo disintegration time and in vitro dissolution of NM from ODTs along with other tablet characteristics was investigated using full factorial design. The optimized ODT contained 5% w/v maltodextrin DE 29, 2% w/v Methocel (R) E15, and 5% w/v NM, disintegrated in less than 10 s and showed more than 70% of NM in ODTs dissolved within 2 min, compared to only 1.52% of NM plain drug and 7.25% of NM in immediate release commercial tablet. Crystalline state evaluation of NM in the optimized ODT was conducted through differential scanning calorimetry, and X-ray powder diffraction. The study suggests that the optimized ODT formulation developed in this work may be an alternative to conventional formulations of NM inconvenient to the patients such as intramuscular or rectal administration.