By Evonik Röhm GmbH
Enteric coatings are often used in pharmaceutical dosage forms to prevent the degradation of acid labile compounds or prevent premature drug release for actives that may irritate the stomach. One of the most widely used polymers for enteric coating is EUDRAGIT® L 30 D-55 (Poly(methacrylic acid-co-ethyl acrylate, 1:1). After the coating process, an additional drying period may be used for certain products. In this case, comparative data between the effects of various post-drying conditions, including drying in coating equipment and oven drying would be very useful. Additionally, many new drugs and biological products (e.g. proteins and peptides) that are being investigated may be stored at low temperatures in order to preserve their stability, especially in early studies when their long term stability has not been fully characterized. In some cases, these actives are acid labile and require an enteric coating. Therefore it is of interest to study the effect of storage of enteric coated products at low temperatures.
The purpose of the study was to investigate the drug release of enteric coated particles subjected to different post drying conditions and storage temperatures. Theophylline granules coated with EUDRAGIT® L 30 D-55 were used as a model drug product. The in-vitro drug release of the coated granules was evaluated using standard dissolution tests for enteric coated products.