Formulation aspects of Solid Dispersions of Simvastatin

The aim of the present work was to improve dissolution rate of Simvastatin, a drug used for the treatment of hyperlipidemia. Simvastatin is a selective competitive inhibitor of HMG CoA reductase. However its absolute bioavailability is 5% hence to increase it further solid dispersions were prepared. Solid dispersions were prepared with PVP-K30 at different drug: polymer ratios. These solid dispersions were analyzed for in-vitro dissolution profile, and solid dispersions of drug with PVP-K30 at all drug: polymer ratios had shown improved dissolution rate. FTIR studies showed no interactions among drug and polymers. The study shows that the dissolution rate of Simvastatin can be enhanced to considerable extent by solid dispersion technique with PVP-K30. From the above study it can be concluded that solid dispersion of Simvastatin improved the drug dissolution profile. It was found that by varying the drug polymer ratio and by using different methods of preparation of solid dispersion, the dissolution rate of pure drug can be enhanced. The present work concluded that solid dispersion technology can be used successfully to enhance the dissolution rate of poorly soluble drugs.