Actelion Ltd: American Thoracic Society Publishes Abstract on Positive Long-Term Survival Data with Tracleer (Bosentan) in Patients with Primary Pulmonary Hypertension


ALLSCHWIL/BASEL, Switzerland, April 23, 2003 (PRIMEZONE) -- Actelion Ltd. (SWX:ATLN) (Other OTC:ALIOF):

At the upcoming American Thoracic Society (ATS) Scientific Sessions to be held in Seattle, Washington, USA in May 2003, Dr. Vallerie McLaughlin, MD, Rush Presbyterian Medical Center, Chicago, will present an independent analysis of long-term follow-up data which showed a positive long-term survival benefit involving 169 primary pulmonary hypertension patients who were treated with Tracleer(R) as first line treatment and were enrolled in the Tracleer(R) pivotal registration studies.

The abstract covering Dr. McLaughlin's presentation has become available on the ATS website http://www.abstracts2view.com/ats.

Per American Thoracic Society requirements, Actelion will be able to publicly comment on the positive survival data after Dr. McLaughlin has made her presentation to the medical community who will be attending the ATS symposium "Pulmonary Hypertension: Mediators and Therapeutic Options," scheduled for Monday, May 19, 1:30 pm - 4:15 pm at the Sheraton Seattle Hotel and Tower, Grand Ballroom B (2nd Floor). A more detailed announcement of the data will be distributed at that time.

Actelion Ltd

Actelion Ltd is a biopharmaceutical company with its corporate headquarter in Allschwil/Basel, Switzerland. Actelion's first drug Tracleer(R), an orally available dual endothelin receptor antagonist, has been approved as a therapy for pulmonary arterial hypertension. Actelion markets Tracleer(R) through its own subsidiaries in key markets worldwide, including the United States (based in South San Francisco), the European Union as well as Canada and Switzerland. Actelion, founded in late 1997, is a leading player in innovative science related to the endothelium -- the single layer of cells separating every blood vessel from the blood stream. Actelion focuses on the discovery, development and marketing of innovative drugs for significant unmet medical needs. Actelion shares are traded on the SWX Swiss Exchange (ticker symbol: ATLN).


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