In vitro potency assay for hepatitis A vaccines: Development of a unique economical test

Prior to the official release of each Hepatitis A vaccine lot to the market , a quality control performed by a National Control Authority requires an i n vivo or an in vitro potency assay. At the beginning of our work, no stand ardised in vitro test common to all hepatitis A vaccines was available for both manufacturers and National Control Laboratories. In this study, a uniq ue polyvalent enzyme-linked immunosorbent assay (ELISA) method was develope d to appraise all commercially available HAV vaccines. After comparing a di rect and an indirect sandwich method with commercial antibodies, the indire ct assay was selected and an evaluation of sensitivity, linearity, accuracy and precision was performed before being applied to HAV antigen determinat ion from four different manufacturers. The results are satisfactory and inc line us to use routinely this method to release Hepatitis A vaccines.