Product Design

Abstract

Pharmaceutical companies, hospital and community pharmacies prepare medicines. Although batch sizes vary greatly, the underlying principles of product devel- opment are comparable and driven by physical chemistry, physiology and pharmacokinetics. When the medication is meant for only a small group of patients or even for individual use, these principles cannot be fully elaborated and formulation becomes more and more based on risk assessment. The design phase encompasses all aspects of converting an idea into a safe and efficacious product. To ensure quality, all factors affecting product perfor- mance have to be identified and critical limits or specifications defined. Medicines can be designed according to the concept of Quality by Design (QbD), using its elements of defined target product quality profile, robust product and preparation processes, critical quality attributes, process parameters, sources of variability, and controlled preparation processes. The QbD concept is essential for large scale produc- tion but also assists in effective design of pharmacy preparations. Starting with an active substance, the prod- uct profile and biopharmaceutical and pharmacokinetic qualities, the administration route and a specific dosage form are chosen. Physico-chemical properties of the active substance limit these options. Formulation and preparation method have to be designed. Based on critical product and process characteristics, the ‘design space’ can be defined. A robust process is associated with a large design space. Proper documentation of the design process assists in troubleshooting or when modifications occur. Successful life cycle management is underpinned by an active attitude towards improving the design qual- ity of the product.