Background

Vaccines have never been available during influenza pandemics, including the last two, in 1957 and 1968, when annual influenza vaccination against epidemic strains was fully established. Historically, pandemic viruses have been discovered only after the start of international transmission, with global spread completed in approximately 6 to 8 months. This left insufficient time to initiate vaccine research and development, let alone vaccine manufacturing, distribution and administration.

The current outbreak of H5N1 is a stark warning that conditions are highly favourable for the emergence of a pandemic virus. For the first time in history, there is a window of opportunity to consider using a pandemic vaccine in humans at a time when a virus with significant pandemic potential is circulating in large parts of Asia.

There are two major preconditions for such use: the optimal formulation of pandemic vaccines needs to be established through clinical trials, and vaccine manufacturers need to register pandemic vaccines with their licensing agency. Such registration, done with a “template” influenza subtype which will eventually be replaced by the strain actually causing the pandemic, is a condition which every manufacturer must fulfil to produce pandemic vaccine, regardless of when the next pandemic occurs and which strain causes it.

Global capacity to produce influenza vaccines is strictly limited. At the same time, public health sees a compelling need to ensure that this capacity can be maximized when it matters most: during the emergence of a new pandemic strain. Only a small number of influenza vaccine companies have begun the preparatory work for pandemic vaccine licensing. Their clinical trials will contribute to establishing the optimal formulation of a pandemic vaccine against the currently circulating H5N1 strain. However, production capacity for a pandemic vaccine will be vastly inadequate unless other companies engage in vaccine seed development and preparation of batches for clinical testing. More clinical testing of different formulations of an H5N1 pandemic vaccine is also needed to develop antigen-sparing strategies that help make the best use of limited capacity.

Objectives and expected outcome

• To review current status of development and production of an influenza pandemic vaccine.
• To discuss shared responsibilities among the parties concerned (companies, governments, WHO)
• To explore possible solutions to problems that impede expedited vaccine development, particularly concerning the initiation of clinical batch production and clinical trials, and discuss the next steps in moving this process forward.

Participants

The meeting is targeted at decision-makers in influenza vaccine companies, government representatives of countries where companies are located and related national and international vaccine licensing agencies. In addition, representatives will be invited of the Global Health Security Action Group of the G7 + countries´ Influenza Pandemic Working Group, who have been extensively involved in pandemic vaccine issues at governmental levels. Furthermore, a representative has been invited from the International Federation of Pharmaceutical Manufacturers Association and the Developing Countries Vaccine Manufacturers Association.

For further information contact WHO communication officers, Dick Thompson, at 4122 791 2684 (email: thompsond@who.int), or Maria Cheng, 4122 791 3982 (email: chengm@who.int). This meeting will be closed to the press but there will be a press conference at its conclusion.