Conference Dates

June 6-11, 2010


Pandemic influenza is a recurring threat throughout history. Characterized by rapid spread and high attack rate, the features of pandemic influenza are grounded in the lack of immunologic experience with pandemic virus subtypes in the majority of the human population alive during the outbreak. Immunization is regarded as a key tool in preparing for, and mitigating, pandemic influenza. Unfortunately, capacity to manufacture sufficient inactivated influenza antigen by currently-licensed processes remains challenging, and this problem is amplified by the very short timeline for production and distribution that may be available. GSK has addressed the pandemic influenza challenge by application of the AS03 adjuvant system, a tocopherol-based emulsion. Vaccines containing AS03 and inactivated split virion influenza antigens manufactured by two distinct processes at GSK’s facilities in Germany and Canada have been evaluated in pre-clinical systems and in humans with closely similar results. AS03 has been shown to provide a marked antigen-sparing effect, especially for difficult antigens such as H5N1. In addition, AS03 added to inactivated influenza vaccines has also allowed induction of cross-reactive humoral and cellular responses to antigenically diverse H5N1 viruses. By broadening cross-reactivity, AS03 might allow stockpiled vaccines to be deployed as a first counter-measure, even if the vaccine antigen available is not closely antigenically matched to the threat virus. The deployment of GSK’s AS03-adjuvanted vaccines Pandemrix™ and Arepanrix™ to confront the recent swine-origin H1N1 pandemic experience has required the management of multiple novel challenges. These have included the rapid conduct of clinical trials to satisfy a range of regulatory and public health needs, real-time evolution of dosing recommendations as the vaccines were used, consideration of the potential interaction of pandemic and seasonal vaccines, the use of non-traditional sources of data for safety and effectiveness, and safety monitoring of mass-vaccination campaigns on an unprecedented scale. GSK’s experience with, and learnings from, some of these challenges will be discussed.