Butterworth has stressed the importance of excipients testing by pharmaceutical and biotech companies in order to ensure quality and performance.
Active Pharmaceutical Ingredient (API) is the term used to refer to the biologically active component of a drug product, while an excipient is often defined as an inactive substance that serves as the vehicle or medium for a drug or other active ingredient. This terminology often leads to the misunderstanding that an excipient is an inactive ingredient.
That excipients are referred to as inactive, appears to derive from the fact that they are seen solely as ingredients used to produce a tablet, cream or solution allowing patients to receive the API. However, excipients often perform vital and active roles in medicines, such as helping to control the bioavailability of an API to meet specific requirements and assisting with binding and coating in the drug manufacturing process. They can also perform a critical role in stabilising unstable components such as proteins, can be used as colourings and flavourings to mask unpleasant tastes or odours and to allow easy identification of different drugs.