this study investigate the application of melt extrusion for the development of an oral retard formulation with a precise drug release over time.since adjusting the formulation appears to be the utmost importance in achieving the desired drug release patterns, different formulation of laminar extrudate were prepared according to the principle of experimental design, using a design for mixture to assess the influence of formulation composition on the in vitro drug release from the extrudates after 1 h and after 8 h. the effect of each component on the two response variable was also studied.