The development of medicinal products is widely seen as an important public health issue. The approval of new drugs requires clinical trials to ensure efficacy and safety. Every

country has its own regulatory authority, which is responsible for enforcement of regulations and issuance of guidelines to regulate the marketing of drugs. The evaluation activity of the competent authority, prior to the authorization of a drug and its approval for marketing, aims to ensure that the product offers the necessary guarantees of quality, safety and efficacy. In the United States, the Food and Drug Administration (FDA) is responsible for protecting and promoting public health and supervising the drug approval process. European LY294002 drug approvals are overseen by check details the European Medicines Agency (EMA). The EMA is responsible for the scientific evaluation of applications for the authorization to market medicinal products. The market authorization of clotting factor concentrates for the treatment and prevention of bleeding in patients with haemophilia in Europe and the US follows the guidelines of the two principal regulatory authorities. Since these guidelines lack a uniform standard of recommendations for pre- and postregistration, a project group assembled by the Factor VIII/IX Subcommittee of the Scientific and Standardization Committee (SSC) of the International

Society on Thrombosis and Haemostasis (ISTH) is developing a set of recommendations for the optimal design of clinical studies and trials for clotting factor concentrates for the treatment of haemophilia A and B. Clinical

trial design recommendations promoted by the ISTH SSC project group are based on four priority considerations: (i) assessing the harmonized safety and efficacy data required by regulatory agencies for product registration, (ii) exploring the potential impact of alternative statistical approaches and innovative trial design on the preauthorization regulatory requirements medchemexpress for product safety and efficacy determination, (iii) examining the current scientific concepts of immunogenicity and neo-antigenicity and their potential influence on clinical trial design and novel approaches to antibody surveillance and (iv) preparing the assessment for the availability of innovative clinical trial design strategies and models that may be suitable for rare diseases such as haemophilia. In the debate on the harmonization between the FDA and the EMA, the ISTH SSC project group has two priority areas, namely, inhibitor assay methodology and the revision of the demand for paediatric trials for pre- and postregistration assessment. Currently, safety aspects in trials for clotting concentrates include viral safety while the most significant adverse event is that of immunogenicity.