Optimized Formulation of Rizatriptan Benzoate Tablet by a Central Composite Design/Response Surface Methodology

Purpose To optimize the formulations of rizatriptan benzoate tablets by a central composite design/response surface methodology. Methods Independent variables were microcrystallinecellulose (MCC) content and crospovidone(PVPP) content,and disintegrating time was dependent variable. Linear or nonlinear mathematic models were used to estimate the relationship between independent and dependent variables. Response surfaces were delineated according to best-fit mathematic models, and optimum formulations were selected thereform. Prediction was carried out through comparing the observed and predicted values. Results Disintegrating time was not linear to MCC ocntent and PVPP content. Regression coefficients of se-cond-order and third-order quadratic models were as high as 0.992 4 and 0.998 5, respectively. Optimum formulation was proposed to contain MCC 3.0 g and PVPP 0. 3 g. Bias between observed and predicted values of disintegrating time was - 2. 68 % . Conclusions It shows that the optimum mathematic model is highly predictive.