[Experience in scaling up the film coating process for theophylline sustained-release pellets in mass production]

The scale-up of the film coating process for the production of Bronchoretard pellets (theophylline, CAS 58-55-9) is an example for the successful setup of a modern production technology designed to meet the increasing GMP requirements while taking into consideration ecological and economical aspects. This technology provides a reduction in polymer losses on drying from approx. 20% to under 5% and a distinct improvement in the reproducibility of the in vitro dissolution profiles. Double batch sizes and higher spray rates allow for a substantially higher batch turnover. A production line installed exclusively for Bronchoretard pellets and specific process optimization measures resulted in considerably lower lag-times of the equipment.