European Medicines Agency finds no link between swine flu vaccine and narcolepsy
The European Medicines Agency, a decentralised agency of the European Union, located in London, which is responsible for the scientific evaluation of medicines developed by pharmaceutical companies for use in the European Union, reports through a press release dated 09/23/10, that after reviewing all the available data and reports on the supposed link between the swine flu vaccine, Pandemrix, and the sleeping disorder of narcolepsy, that “the available evidence was insufficient to determine whether there is any link between Pandemrix and reports of narcolepsy, and that further studies were necessary to fully understand this issue.”
Pandemrix was used in Europe during the 2009 H1N1 influenza pandemic, at which time up to 30 Millions Europeans received the vaccine. This year, up to September 17, 2010, 81 reports suggestive of a connection between the vaccine and narcolepsy were collected. The Committee maintains that so far the risk-benefit of the vaccine is still positive and no restrictions in use are necessary.
It is important to keep in mind however, that the EMA Committee is not saying that there is no connection between Pandemrix and narcolepsy, but only that the current evidence is insufficient to establish a causal relationship between the two. They caution that more research is needed to reach solid conclusions. In fact, they are continuing the analysis and review of the reports received.
The ongoing review is complex and will take some three to six months to complete. The Agency is working with experts from across the European Union to carefully scrutinise all available reports. Owing to a potential overlap of narcolepsy symptoms with several other neurological and psychiatric disorders, diagnosis is very often not confirmed until several years after symptom onset.
The number of reports of narcolepsy that occurred in children in some countries seems to be higher than expected in comparison with data from previous years. However, there are many uncertainties in the available information that need to be clarified. These include a possibility that earlier diagnoses of narcolepsy have contributed to this apparent increase. Also, the influenza pandemic itself may have contributed to a change in the rates of narcolepsy. These factors need to be assessed before firm conclusions can be drawn.
The ongoing review will require new observational (epidemiological) research in order to reach any firm conclusions on whether there is a link between Pandemrix and narcolepsy.