Formulation and In-vitro comparison of Extended Release Pellets of Venlafaxine with Innovator

The study aims at developing novel extended release pellets of venlafaxine. The main objective of the work was to develop robust extended release formulations of Venlafaxine (test formulation) for regulated markets having comparable in-vitro dissolution profile with Innovator product - Effexor® XR (Reference Product). Venlafaxine spheroids were made using extrusion spheronization technique. The release of the drug from the spheroids was controlled by applying a coating comprising ethyl cellulose as rate controlling polymer. The coated pellets were then encapsulated in the hard gelatin capsules. The in-vitro dissolution studies were conducted to evaluate the release of the drug venlafaxine from the coated spheroids contained in capsule at pH 6.8 using phosphate buffer. The in-vitro dissolution profile of the test compositions was compared with Reference Product Effexor XR. The results obtained showed that the test formulations had higher percentage release of venlafaxine in initial time period. Therefore, a better control on the release was desired. During the manufacturing of spheroids, it was observed that more fines were generated during the extrusion spheronization, which is not suitable for large scale production of the formulation. Accordingly batches were optimized using different types of binder and coating composition. Effect of the binder and percentage coating was studied. The drug release of venlafaxine using Povidone K30 as binder, Ethyl cellulose and Acryl-EZE MP 93018508 white as release control polymers was compared with innovator’s drug release and was found to be equivalent. From the results, it was concluded that use Povidone K30 as binder during extrusion spheronization process results on generation of less fines, thus increases the yield of the product. Also, the formulation containing dual coating of Ethyl cellulose and Acryl-EZE MP 93018508 on the spheroids containing Povidone K30 as binder showed the dissolution profile similar to that of the Reference Product Effexor XR.