LAUSR

In vitro dissolution/release tests are an indispensable tool in the drug product development, its quality control and the regulatory approval process. Mucosal drug delivery systems are designed to provide both local and systemic drug action following ocular, nasal, oromucosal, vaginal or rectal administration. They exhibit significant differences in formulation design, physicochemical characteristics and drug release properties. Therefore it is not possible to devise a single method which would be suitable for release testing of such versatile and complex dosage forms. Different apparatuses and techniques for in vitro release testing for mucosal delivery systems considering the specific conditions at the administration site are described. In general, compendial apparatuses and methods should be used as a first approach in method development when applicable. However, to assure adequate simulation of conditions in vivo, novel biorelevant in vitro dissolution/release methods should be developed. Equipment set up, the selection of dissolution media and volume, membrane type, agitation speed, temperature, and assay analysis technique need to be carefully defined based on mucosal drug delivery system characteristics. All those parameters depend on the delivery system and physiological conditions at the site of application and may vary in a wide range, which will be discussed in details.