Abstract
Laminated controlled release (CR) tablets of diclofenac were developed employing hydroxypropyl methylcellulose 1000 (HPMC-1000) and hydroxypropyl methylcellulose 15000 (K-15 Methocel) as matrices. A priming dose of diclofenac was contained in the first layer and the maintenance dose was in the second layer in the HPMC-1000 or K-15 Methocel matrix to obtain release rates of the drug of approximately 8 mg h−1 for an extended period of time. The comparative in vivo evaluation of the K-15 Methocel tablet and Voltarol® 50 (diclofenac 50 mg enteric tablet) in human volunteers showed that, with the matrix tablet, a quicker onset of action and a more uniform plasma level of diclofenac around the maximum concentration could be maintained as compared to Voltarol® 50. A correlation between in vitro and in vivo release was found, with a correlation factor of 0.9040.