Sepracor Inc announced that it has submitted a New Drug Application (NDA) to the US FDA for Xopenex HFA (levalbuterol tartrate HFA) Inhalation Aerosol, a hydrofluoroalkane (HFA) metered-dose inhaler (MDI) for the treatment or prevention of bronchospasm in adults, adolescents and children four years of age and older with reversible obstructive airway disease, such as asthma and chronic obstructive pulmonary disease (COPD). MDIs are hand-held, pressurized canisters that deliver inhaled medications directly to the lungs.

Under the Prescription Drug User Fee Act, the FDA has 60 days after submission to review an NDA in order to determine if the application may be filed. The filing of an application means that the FDA has made a threshold determination that the application is sufficiently complete to permit a substantive review.

Sepracor's MDI development program included approximately 1,870 pediatric and adult subjects and 54 studies (preclinical and clinical). In 2003, Sepracor completed its Phase III studies of Xopenex HFA. In each of the three, large-scale, pivotal Phase III trials that Sepracor conducted, the Xopenex HFA MDI was well tolerated and met the targeted efficacy endpoints in both adults and children with asthma. In the primary airway function measure, FEV1 (a test of lung function that measures the amount of air forcefully exhaled in one second), the Xopenex HFA MDI produced statistically and clinically significant improvements relative to placebo (p<0.001).

"The number of patients who use MDIs is more than twice the number of patients who use nebulizers to deliver their respiratory medication," said William J. O'Shea, president and chief operating officer at Sepracor Inc.

"Since MDIs are easily portable, they are generally the preferred treatment option for teenagers and adults, while nebulizer therapy is often preferred for young children and older adults for whom a nebulizer is easier to use," stated Mark H.N. Corrigan, M.D., executive vice president, Research and Development at Sepracor. "Introduction of the Xopenex HFA MDI would provide patients with reversible obstructive airways disease with a new Xopenex delivery system, allowing them to quickly and conveniently manage bronchoconstriction associated with their disease."

Asthma is a chronic lung disorder characterized by reversible airway obstruction and the pathologic finding of airway inflammation. According to the American Lung Association, approximately 26 million Americans have been diagnosed with asthma in their lifetime. It is the most common childhood illness and affects approximately 8.6 million children in the U.S. under the age of 18. Short-acting beta-agonists are the most-prescribed asthma therapy among primary care physicians and pediatricians in the U.S., according to IMS Health information.

The U.S. short-acting bronchodilator MDI market potential at branded prices, assuming parity pricing to branded Proventil HFA, is approximately $1.6 billion.

Sepracor currently markets Xopenex brand levalbuterol HCl inhalation solution for use with a nebulizer through its primary care and hospital sales force. Xopenex inhalation solution is FDA approved for use in a nebulizer at 0.31 mg and 0.63 mg dosage strengths for treatment of children 6 to 11 years old, and in 0.63 mg and 1.25 mg dosage strengths for patients 12 years of age and older.