New study results indicate that GSK’s Advair Diskus is more effective than Merck’s Singulair in patients suffering from asthma and seasonal allergies.  Combining the two drugs resulted in “no additional improvements in asthma control,” according to the study.

Conducted by the National Jewish Medical Research Center, the study found that adding fluticasone propionate nasal spray – the active ingredient in Flonase – to Advair saw “significant improvement in daytime nasal symptoms compared to patients treated with Advair plus Singulair,” according to a GSK statement.  Flonase’s patent has expired, but Veramyst, another GSK corticosteroid nasal spray containing fluticasone, was approved in April 2007. 

According to Mary Anne Rhyne, director US media relations for GSK, the company isn’t marketing Flonase or Veramyst or other fluticasone nasal corticosteroids in conjunction with Advair at this time.  “The results from this study are encouraging and will give physicians more complete information when prescribing, but it is premature and inappropriate to talk about marketing changes or new indications based on one study,” said Rhyne.

In a separate study to be published in June, the National Jewish Medical Research Center found that girls and children exposed to secondhand smoke benefit more from montelukast, the active ingredient in Singulair.  According to Adam Dormuth, a spokesperson for the National Jewish Medical Research Center, the study intended to establish “biomarkers to help doctors identify cases when Singulair might be appropriate.”

In March, the FDA announced an investigation into a “possible association between the use of Singulair and behavior/mood changes, suicidality (suicidal thinking and behavior) and suicide.”  Additionally, the FDA rejected an application in April for a combination drug – Singulair and Claritin – under development through a Schering-Plough/Merck collaboration.