Extrusion Process for High Active Pharmaceutical Ingredient Loading That Exhibit Controlled Release: Formulations and Evaluation Thereof

Drugs required in a large dose size are difficult to design into a matrix based controlled release drug delivery system (CRDDS) because of the requirement of high amounts of polymers or other matrix formers, along with general excipients. In order to overcome this limitation, preparation of matrix based CRDDS containing high dose of active pharmaceutical ingredient (API) using extrusion as a process were formulated and evaluated which forms the backbone of the present research. Tablets extruded directly from the calibrated modified tablets extruder die exhibited extended release properties, excellent content uniformity; exceptional tablet hardness and friability results over control samples produced via direct compression and showed compliance with pharmacopoeial standards. The in vitro drug release data justifies the release process is diffusion-controlled as all the formulations best fitted into first order release kinetics and Higuchi's equation. To confirm diffusion mechanism results, the data were fit into Korsmeyer-Peppas model, which revealed anomalous transport kinetics. The accelerated stability studies of optimized formulations TEM.2 made it clear that only negligible amount of drug content degraded. Release pattern was almost unaffected and could be claimed to be stable at the end of six months. It can be concluded that, apart from direct compression method of preparation of controlled release matrix tablets of nicotinic acid, extrusion process can also be successfully used as an effective method for the preparation tablets requiring high dose of API.