New asthma device provides once-daily dosing

May 2, 2005

The Food & Drug Administration recently approved mometasone furoate 220 mcg once-daily inhalation powder (Asmanex Twisthaler, Schering-Plough), the first inhaled corticoste-roid to receive clearance for once-daily initiation therapy. Asmanex is approved for first-line treatment of asthma as preventive therapy in patients 12 years of age or older. It is also approved for patients on bronchodilators alone or who require oral corticosteroid therapy, when adding Asmanex may reduce or eliminate the need for oral corticosteroids. Schering plans to launch the product in the fall of 2005.

According to the Centers for Disease Control & Prevention, as many as 20 million people in the United States have asthma. The American Lung Association reports that this potentially serious and life-threatening condition leads to at least two million emergency department visits and more than 5,000 deaths annually. The yearly direct cost of treatment is $9.4 billion.

Previously, the only controller medication approved for once-daily initiation therapy was the leukotriene-receptor antagonist montelukast (Singulair, Merck), said Harold Nelson, M.D., a professor of medicine at the National Jewish Medical & Research Center in Denver. But, he noted, leukotriene-receptor antagonists are not first-line controller medications as recommended by the National Heart Lung & Blood Institute guidelines, because they are not as effective as corticosteroids, which have always been approved for twice-daily administration.

Nelson agreed that, as monother-apy, Asmanex fits into the mild-to-moderate end of the spectrum of persistent asthma. In patients with more severe asthma, he said, the recommendation would be to add a long-acting beta agonist such as formoterol (Foradil, Novartis) to the regimen.

An advantage of Asmanex Twisthaler is that the dry powder delivery system does not use a propellant. The Twisthaler is inhalation driven, thus eliminating the need for hand-breath coordination, said Farris. Dry powder delivery systems are relatively new, so it is very important that patients be instructed in their proper use. He also noted that patients might not feel the release of the medication as they would from an aerosol-driven device, adding that pharmacists in a retail setting could encourage patient compliance by ensuring that patients know how to use the Twisthaler device properly. According to the company, the Twisthaler device provides a numeric dose counter as a visual indicator of the remaining doses.

Compliance is the biggest problem faced by clinicians, said Nelson, particularly with respect to patients taking inhaled corticosteroids. He also pointed out that the pharmacist is the last person the patient interacts with before taking the medication home, so a final reminder about returning for a refill in a month would be useful.

The recommended starting dose of Asmanex is one inhalation daily in the evening for those previously treated with bronchodilators alone or inhaled corticosteroids. For patients previously maintained on oral corticosteroids, the recommended starting dose of Asmanex is two inhalations twice daily.

The manufacturer advised that patients requiring oral corticosteroids be weaned slowly from their use after transferring to Asmanex. Lung function, beta-agonist use, and asthma symptoms should be carefully monitored during the withdrawal of oral corticosteroids. Schering also recommended that patients be observed for signs of adrenal insufficiency, including fatigue, lassitude, weakness, nausea and vomiting, and hypotension.

Asmanex was approved after a lengthy regulatory delay. A company spokesman said the delay had nothing to do with the safety or efficacy of the product. He explained that Schering took painstaking efforts to ensure FDA compliance and to meet its own high standards for reliability and consistency.