The European Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) has recommended that the product information for Pandemrix should be amended to take into account preliminary results from epidemiological studies suggesting a link to narcolepsy, and to advise an individual benefit-risk assessment when considering its use in children and adolescents. This is an interim measure pending the outcome of the European review, expected to conclude in July 2011.

The CHMP reviewed all available data, including new findings from Sweden and France on the suspected link between narcolepsy in children and adolescents and Pandemrix; and concluded that, following the earlier results of an epidemiological study from Finland, the new evidence strengthened the signal in children and adolescents, but that the data had methodological limitations. Preliminary results of the Swedish registry study from October 2009 to December 2010 had indicated a four-fold increase of cases of narcolepsy in children and adolescents (<20 years age) who received Pandemrix compared with unvaccinated people of the same age.

The relationship between Pandemrix and narcolepsy is still under investigation and the EMA will provide updates as new information becomes available.