Glaxo and AstraZeneca Clash on Asthma Drug Claims

GlaxoSmithKline Plc said on Thursday its asthma drug Advair/Seretide beat AstraZeneca Plc’s Symbicort in a 1-year clinical study, reviving rival claims about the two products.

Asthmatics who took Advair had on average 24 more symptom-free days than those on Symbicort in the 688-patient CONCEPT study and experienced nearly 50 percent fewer moderate or severe exacerbations of their disease. Europe’s biggest drugmaker is expected to use the results, published in the journal Clinical Therapeutics, to defend its dominant position in respiratory medicine as AstraZeneca moves to launch Symbicort in the all-important U.S. market in 2006. AstraZeneca, however, said patients taking its drug in the latest trial were effectively under-dosed, since they were given an average of just 1.8 puffs of the inhaled treatment each day. The earlier SUND study, using an average 3.4 puffs a day, had come out in favor of Symbicort. GSK generates around one fifth of its sales from respiratory drugs, led by Advair, which had sales of 2.5 billion pounds ($4.71 billion) in 2004. Both Symbicort and Advair combine bronchodilators for short-term asthma relief with cortosteroids to treat inflammation. AstraZeneca’s medicine uses an adjustable dosing regimen, controlled by the patient, while Advair is given at fixed doses. “The results from this study confirm that to minimize symptoms and lower the risk of exacerbations, patients do better by taking regular stable doses of their controller treatment,” said Darrell Baker, senior vice president at GSK’s Respiratory Medicine Development Center. “The study also shows that short-term adjustment of dose by patients, based on their perception of symptoms, clearly is not the best way to control asthma,” he added. AstraZeneca disputed this interpretation, saying the CONCEPT results conflicted with evidence from eight previous clinical trials, including SUND, involving more than 10,000 patients. The SUND study had showed a 40 percent reduction in exacerbations with Symbicort compared with Advair, while the CONCEPT study showed a 47 percent advantage to Advair. Symbicort, which is widely available in Europe but not yet in the United States, had sales in 2004 of $797 million.(Source: Reuters Health, March 2005)