Continuous pharmaceutical processes new applications – old challenges

Pharmaceutical products are intricate mixtures of a drug (active) with multiple excipients manufactured usually through various complex processes within a highly regulated manufacturing and product performance environment. Current pharmaceutical manufacturing is a scaled up version of the historical apothecary based practices and recent developments have highlighted that the intrinsically empirical nature of the entire system is not optimal when compared against contemporaneous requirements. Continuous processing is viewed as a development that can be applied to pharmaceutical manufacturing systems to resolve these empirical deficiencies. The production of active pharmaceutical ingredients and solid oral dosage forms using continuous processes is a current target since this would cover the majority, by volume, of pharmaceutical products. The potential processes and challenges for these products will be examined and compared with existing continuous processes (e.g. water for injection) which the industry has traditionally employed. The implementation of this radical transformation will require development of existing technology, instrumentation and regulation with continuous reference to historical practices.