Swiss become the first to bulk buy pre-pandemic bird flu vaccine

Oct 19 2006

Switzerland has apparently ordered enough of an experimental bird flu vaccine to inoculate it's entire population.

In so doing the Swiss have become the first country to bulk buy a supply of GlaxoSmithKline's bird flu vaccine for humans.

In trials earlier this year the vaccine demonstrated a more than 80 percent strong immune response in test subjects.

The vaccine has an extra ingredient in the vaccine formulation which is designed to increase the immunogenicity of the vaccine as well as potentially offering protection against variant virus strains.

According to Europe's biggest drug maker the Swiss Federal Office of Public Health has placed an order for 8 million doses of its H5N1 vaccine, enough to protect its entire population in the event of a influenza pandemic.

The vaccine is expected to be supplied and stockpiled in early 2007 as soon as the Swiss regulatory agency, Swissmedic, has reviewed and approved the regulatory file for the product.

Glaxo is also working with other governments across Europe on pandemic preparation plans and aims to apply for approval for the vaccine with the European Medicines Agency by the end of 2006.

Glaxo's pre-pandemic vaccine uses only a very low dose of active ingredient based on the bird flu virus from Vietnam.

This means the vaccine will stretch further which is vital if a vaccine has to be produced quickly for millions of people around the world.

The challenge has always been how to make the maximum number of shots from the minimum amount of antigen, or active ingredient, in the shortest possible time.

Though the pre-pandemic vaccine offers protection against the deadly H5N1 avian flu virus currently circulating, how it will impact on any mutated strain of virus is uncertain.

But experts believe the vaccine will in effect "prime" the immune system and a better and stronger effect will then be achieved from a later, better-matched vaccine.

Should a flu pandemic break out, anyone using the H5N1 vaccine would need further immunization with a vaccine appropriate to the actual pandemic, in order to be fully protected.

An exact vaccine matching the pandemic strain will not be able to be created until at least six months after the strain's emergence.

Since 2003 the H5N1 strain of avian influenza has spread rapidly out of Asia and into parts of Europe killing along the way more than 150 people and millions of birds, who have either died from the virus or been culled because of it.

Almost all human cases to date have been the result of close contact with infected birds.

Experts worry that should the virus mutate and acquire the ability to pass easily from human to human, which is quite likely, it could trigger a world wide pandemic that could kill millions.

Drug companies Sanofi-Aventis, Novartis AG and Baxter International are also racing to develop pandemic H5N1 vaccines.