A US regulatory advisory panel is pushing for stronger warnings directed at children to be put on the labels of GlaxoSmithKline’s asthma drugs Serevent and Advair.

The US Food and Drug Administration’s Paediatric Advisory Committee has reviewed nine new adverse event reports over a year in children taking GSK’s long-acting beta2-agonists Serevent (salmeterol) and Advair (salmeterol/fluticasone), including five deaths over a year. Other studies were also looked at which revealed increased hospitalisation for youngsters taking these inhaled treatments.

The FDA committee declared that the warnings on Serevent and Advair need to be more specific to children and that it should also include language that the drugs increase the risk of asthma-related hospitalisations. The agency also noted that it plans to convene an advisory panel for further assessment of the risk/benefit profile of the drugs at a later date. Reports of the meeting state that at least two panel members said the data was so convincing that Serevent should be pulled from the market altogether.

The latter is not a huge seller anymore for GSK but Advair certainly is and made up the vast majority of the drugs’ combined third-quarter sales of £835 million. A further warning could hurt those sales but the UK-headquartered drugmaker is standing its ground.

GSK issued a statement saying that there is no new safety information that changes the benefit-risk evaluation of Serevent or Advair “which warrants another review at this time”. The company noted that asthma-related deaths in the USA have declined 29% since the drugs became available in the mid- 1990’s, and stressed its “confidence in the established safety profile of Advair and Serevent when these products are used according to their labels”.

In March last year, GSK came to an agreement with the FDA to include a 'black box' warning of asthma death in the labelling of the two drugs. This was prompted by data from a large placebo-controlled US study that compared the safety of Serevent or placebo against background asthma therapy and found an increase in asthma-related deaths in patients receiving the GSK drug (13 deaths out of 13,176 patients treated for 28 weeks on salmeterol versus three deaths out of 13,179 patients on placebo).

The news on the asthma drugs follows the PAC’s recommendation that GSK’s flu drug Relenza (zanamivir) should carry an additional warning about the possibility of patients suffering hallucinations and delirium when taking the treatment.