Sepracor files IND to initiate clinical trials on norastemizole, improved allergy drug.

MARLBOROUGH, Mass.--(BUSINESS WIRE)--Jan. 9, 1996--Sepracor Inc. (Nasdaq: SEPR) today announced that it has filed an Investigational New Drug (IND) application with the FDA with respect to Phase II clinical trials on norastemizole, a third-generation antihistamine and potentially improved allergy therapy.

"We are eager to begin our clinical development of norastemizole, as it has the potential of becoming a very successful nonsedating antihistamine, appropriate for a wider range of patients than its parent drug, Hismanal," said Timothy J. Barberich, Sepracor's President and Chief Executive Officer.

Norastemizole is an active metabolite of astemizole, a nonsedating antihistamine which is marketed by Janssen as Hismanal. Like Seldane, another nonsedating antihistamine, Hismanal has a black box warning in its package insert describing its association with cardiac arrhythmias. Based on extensive preclinical studies, Sepracor believes that norastemizole will be an effective treatment for allergic disorders, free of the cardiac side effects associated with Hismanal.

"We see norastemizole as a major improvement over current second-generation antihistamines that have the propensity for causing drug interactions and potentially fatal cardiac arrhythmias," said Dr. Gunnar Aberg, Senior Vice President, Research, Sepracor Pharmaceuticals. "Norastemizole offers three major advantages over the second-generation antihistamines: it is the most potent of all the nonsedating antihistamines, it lacks the cardiotoxicity that has troubled most second-generation antihistamines, and it is very well absorbed after oral dosing."

With clearance to begin clinical trials, the company will conduct a series of clinical pharmacology studies to evaluate the clinical safety and efficacy of norastemizole. Specifically, parallel to its ongoing toxicological studies on norastemizole, Sepracor will further investigate absorption, possible metabolism and excretion of the new drug in man. Trials of antihistaminic activity and possible effects on other organ activities will also be part of the fast-track Phase II clinical program. These trials are scheduled to begin in the first quarter of 1996 and run throughout the year, providing the foundation for subsequent Phase III clinical studies.

More than 35 percent of people in the U.S. suffer from allergies. The worldwide market for nonsedating antihistamines is currently $2 billion and expanding.

"We anticipate this third-generation antihistamine will offer significant benefits over existing allergy therapies and will potentially expand the market as a viable OTC-switch candidate," said David S. Barlow, President, Sepracor Pharmaceuticals. "We look forward to advancing this major new drug candidate to the clinic."

Sepracor has several patents pending for the use of norastemizole in the treatment of allergic disorders.

Sepracor develops Improved Chemical Entities (ICE) that are enhanced forms of existing, widely sold pharmaceuticals. ICEs, which cover product opportunities with strong market potential, can be developed at significantly less cost, time and risk than New Chemical Entities (NCEs). -0-

Hismanal and Seldane are registered trademarks of Janssen Pharmaceutica Inc. and Hoechst Marion Roussel, respectively.

CONTACT: David P. Southwell

Chief Financial Officer

Sepracor Inc.

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Jean M. Devine

Director, Investor Relations 

Sepracor Inc.

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