EU regulatory guidelines for the clinical evaluation of adjuvants

Abstract Adjuvants have been incorporated into vaccines for decades to improve the immune response to vaccine antigens. In developing new vaccines or simply improving existing vaccines, interest in adjuvants has been growing rapidly, with various types of adjuvant (some novel; some already incorporated into specific vaccines) used in clinical research or under development. The development of adjuvants is generally closely linked to the development of a specific vaccine. With the adjuvant being an integral constituent of the final medicinal product, current legislation does not foresee authorization being granted for an adjuvant as a stand-alone product. A dedicated EU guideline addresses the quality non-clinical and clinical development of vaccine adjuvants, and this guidance needs to be considered alongside the specific guidelines for medicinal products in general. This paper provides an overview of the requirements for developing or modifying an adjuvanted vaccine. The authors also address the experience gained for the adjuvanted 2009 H1N1 pandemic influenza vaccine and its implications.