Clinical trials are the primary means of determining the safety and effectiveness of new drugs. Blinding is an important aspect of trial design that involves intentionally concealing the identity of treatments from patients and investigators to avoid bias. The majority of non-commercial clinical trials investigate new iterations of already-licensed products. It is difficult to conceal the identity of licensed products as participants may be familiar with the product (e.g. markings, taste). The identity of a tablet can be concealed by insertion in a capsule with a filler to prevent ratting (a process termed over-encapsulation (Fig. 1)). The European Medicines Agency (EMA) requires evidence from a certified test laboratory that overencapsulated tablets meet the same drug release criteria as the unmodified tablets. Given the slight degree of modification, investigators argue that such a process is unlikely to alter release characteristics and therefore that they should be able to provide just a written technical justification in order to waive this time-consuming and costly regulatory requirement. In a study currently under review by the European Journal of Pharmaceutical Sciences, we showed over-encapsulation had no effect on release from four tablet products. It is the purpose of the proposed research to assess drug release from overencapsulated tablets after storage for 12 months – a test also requested by the EMA. We aim to submit a letter to an appropriate medical journal highlighting the findings of this research to the wider medical community thereby contributing to the debate on the relevance of this regulatory test.
