Yahoo News, in an article by Reuters, is reporting this evening on data that links GlaxoSmithKline's Pandemrix, a pandemic flu vaccine, to an increase in the cases of narcolepsy in European children. A similar vaccine is awaiting approval in the United States. Data recently published in the British Journal of Medicine, is causing concern among regulators. The United States Centers for Disease Control and Prevention is sponsoring a new study between adjuvant flu vaccines and narcolepsy, with results expected in 2014. On February 26, the CDC issued an official statement on the discontinued use of Pandemrix in Europe after the British study results were published.
The British study found that children who were given the Pandemrix vaccine during the H1N1 swine flu pandemic in 2009 and 2010 had an increased risk of 14 fold for developing the debilitating and chronic sleep disorder. Other studies conducted in Sweden, Ireland and England had the same results; a problem for future approvals and use of vaccines like Pandemrix which contain AS03, a newly developed adjuvant which significantly boosts the body's immune response. Although not conclusive, scientist suspect that AS03 may be the cause of the increased cases of narcolepsy.
GlaxoSmithKline has a nearly identical vaccine containing AS03 being considered by the Food and Drug Administration for use in the case of an H5N1 bird flu epidemic. The H5N1 bird flu virus was initially found in humans in Hong Kong in1997. It started to spread through Southeast Asia during 2003. According to the World Health Organization, bird flu has a substantially higher death rate in comparison with swine flu; a 59 percent mortality rate.In November, a 14 person advisory panel to the FDA cast a unanimous vote to recommend the vaccine in the case of an outbreak of bird flu.
Even after considering the European study results, their conclusion was that the benefits outweighed the risks. GlaxoSmithKline data shows that out of approximately 30 million doses of Pandemrix were given during the epidemic, resulting in 800 cases of narcolepsy. Most of the cases involved children. GlaxoSmithKline says that the evidence is insufficient to prove that Pandemrix is the cause. However, the company does acknowledge the association.
Doctor Melinda Wharton, acting director of the National Center for Immunization and Respiratory Disease at the CDC was an advisory committee member. She said, "This is an evolving situation so there will continue to be more information to inform the decision making process. Given that, I think this is a situation where the risk/benefit assessment could still favor the use of the vaccine, particularly in adults, as we are looking at a disease with an extremely high mortality rate."