Formulation, development, and optimization of immediate release nateglinide tablets by factorial design.

In the present study, selection of superdisintegrants among sodium starch glycolate, cross povidone, Starch-1500 and cross carmellose sodium (CCS) was carried out for development of immediate release nateglinide tablets (NTG). A 3(2) full factorial design was used to investigate the influence of two independent variables, i.e., amount of selected superdisintegrants and hardness of the tablets, on two dependent variables, i.e., disintegration time and percentage of drug release at 30 min (DR(0.5h)). The results revealed that CCS was the best superdisintegrant for the development of immediate release tablets of NTG. The sign of the coefficient of the polynomial equation signified that the disintegration time was decreased and DR(0.5h) was increased by decreasing the hardness of the tablets as well as by increasing the concentration of CCS in the tablets. A checkpoint batch of the tablets was prepared by changing the value of independent variables within the range used in the preparation of factorial batches of tablets to check the validity of the evolved optimized mathematical model. Stability studies of optimized formulations indicated that there was no significant change in the physical parameters, disintegration time, and percentage of drug release of tablets. The systematic formulation approach helped to understand the effect of formulation processing variables.