Sepracor Estorra NDA Filing Planned By Mid-Feb.; Xopenex MDI By Year-End

Sepracor is planning an NDA filing for its sleep disorder drug Estorra by Feb. 15, followed by a submission for its Xopenex metered dose inhaler formulation before year-end.

"We will be filing the Estorra NDA by Feb. 15....We expect to file the Xopenex MDI NDA by year-end, and (R,R)- formoterol and Soltara by mid-year '04," CEO Timothy Barberich said during an analyst call Jan. 28.

Sepracor is seeking an indication for transient and chronic insomnia for Estorra (eszopiclone). The indication will be for "extended, long-term use of the drug, and a specific mention of safety and efficacy in the elderly population," VP-Medical Affairs Thomas Wessel, MD/PhD, said.

Six Phase III trials have been conducted in support of the NDA. Two of the trials focused on elderly patients.

Sepracor also expects a claim for "sleep maintenance in our label," Wessel said. "FDA had previously indicated to us that if we executed this long-term study, it would appear in our label." Barberich added: "As far as we know, this is the first time that a drug has been demonstrated, in a double-blind placebo control study, to be safe and effective for a six-month period of time without tolerance."

Sepracor will expand its primary care sales force by the end of the year in anticipation of FDA approval for the anti-insomnia agent.

"The size of the force we're looking, at the moment, to expand to is about 1,000 representatives, with a separate specialty force as well," Exec VP-Finance David Southwell said.

"Estorra is complete. This is the most complete NDA that anybody's probably ever encountered," Barberich declared.

In March 2002, Sepracor expanded its primary care sales force to 500 reps to support Xopenex (levalbuterol) marketing. During the second half of 2002, Xopenex increased its share of new prescriptions among primary care physicians, the company reported.

Also, Sepracor will attempt to increase Xopenex' hospital market share. "We actually calculate that every patient coming out of hospital is actually worth about 1,000 vials to us in terms of retail sales," Southwell said.

Xopenex MDI NDA will be filed before the end of the year, Sepracor said.

In the first half of 2004, Sepracor will file (R,R)-formoterol, the metabolite for Novartis' Foradil , for treatment of bronchospasms in patients with chronic obstructive pulmonary disease. The NDA will be supported by two Phase III studies currently ongoing in 1,600 patients.

Sepracor will also re-file Soltara (tecastemizole), the metabolite for Janssen's Hismanal (astemizole), for allergic rhinitis by mid-2004. Hismanal was removed from the market in 1999 due to cardiac side effects.

FDA deemed Soltara "not approvable" in March 2002, requesting additional data to show that the drug has no potential for QTc prolongation, and citing incidents of phospholipidosis and cardiomyopathy in animal studies (¹ 'The Pink Sheet' March 11, 2002, In Brief).

Sepracor played down concerns about launching Soltara into a market that includes over-the-counter Claritin . The assumption is "that the prescription market will shrink, and the question is by how much. I'd say the consensus is by at least, 25%, but probably not 50%," President W. James O'Shea said.

"The market, even if we attenuated pretty significantly...it's very difficult to go below about $3.5 bil. in size," O'Shea added. "We know it will still be a very sizable prescription market and, I think, very worthwhile to be launching into," he said.

The Claritin OTC switch will not adversely affect Sepracor in the short term. "While Claritin switches OTC, it's likely that some portion of Claritin will also be redistributed across prescription brands, Barberich noted. "Of course we receive no royalty on Claritin, but we do on Clarinex and Allegra, which, together, represent something like 70% of the remaining prescription market."

"We don't think it has a short term impact on Sepracor from a royalty point of view, and we still think that Soltara will be a meaningful product if and when approved," Barberich said.