Application of biorelevant dissolution tests to the prediction of in vivo performance of diclofenac sodium from an oral modified-release pellet dosage form.

In vitro biorelevant dissolution tests enabling the prediction of in vivo performance of an oral modified-release (MR) dosage form were developed in this study. In vitro dissolution of MR diclofenac sodium pellets containing 100mg active ingredient was evaluated under simulated pre- and postprandial conditions using USP Apparatus 3 (reciprocating cylinder, Bio-Dis) and 4 (flow-through cell) and results compared with compendial methods using USP Apparatus 1 (basket) and 2 (paddle). In vivo, the effects of food on the absorption of diclofenac sodium from the pellet dosage form were investigated by administering the product to 16 healthy volunteers pre- and postprandially in a crossover-design study.