Impact of Critical Material Attributes of HPMC on the Release of Gliclazide from Hydrophilic Matrix Tablets

The influence of HPMCviscosity and the degree of substitution hydroxypropyl level (DSHP) on therelease rate of gliclazide was examined. The increase in the HPMC viscosity ledto a significant decrease in the release rate. The second parameter, DSHP,showed a surprisingly high impact on the release rate with higher hydroxypropyllevels leading to a faster drug release. The results demonstrated the need forcontrol on both parameters for formulators of gliclazide tablets in order toensure a consistent drug release performance.