Actelion, Glaxo Stop Development of Insomnia Medicine on Safety Concern

Actelion Ltd. and partner GlaxoSmithKline Plc stopped late-stage development of the experimental almorexant insomnia pill because of concern that patients wouldn’t be able to tolerate the medicine.

The termination of the program follows a review of study data, Allschwil, Switzerland-based Actelion said today in an e- mailed statement. The two companies will continue to work together on developing similar new drugs for use in conditions including sleep disorders, Actelion said.

Almorexant’s discontinuation is the latest in a series of clinical trial setbacks for Actelion. The company’s Tracleer medicine, which dominates the market for a lung condition called pulmonary arterial hypertension, or PAH, failed a test to widen its use last year. Actelion’s clazosentan drug didn’t help patients who had suffered from bleeding in the brain in another study. Switzerland’s largest biotechnology company is looking for new medicines to decrease its dependence on Tracleer, which accounted for about 85 percent of its revenue in 2009.

“Almorexant was part of a diversification strategy to become more than just a PAH company, but that strategy hasn’t worked out so far,” Andrew Weiss, an analyst at Bank Vontobel in Zurich, said in a telephone interview. “This throws up the question of how they’re going to get around the patent expiry of Tracleer.” The drug starts to lose patent protection in 2015.

‘More Reliant’

Actelion shares rose 25 centimes, or 0.5 percent, to 52.20 francs at the 5:30 p.m. close of Zurich trading.

“Actelion is becoming more reliant on its PAH program and this may make purchasing the company as a PAH specialist easier,” Carri Duncan, an analyst at Macquarie Group in Zurich, said in a telephone interview.

Amgen Inc., the world’s largest biotechnology company, has been considering a takeover bid for Actelion, according to people familiar with the situation. Actelion’s Chief Executive Officer Jean-Paul Clozel has said the company should remain independent.

“It clearly puts Clozel in a vulnerable position in terms of criticism from the board,” Duncan said.

Actelion sold rights to almorexant to Glaxo in 2008 for as much as 565 million francs ($598 million), with additional payments that could have risen to as much as 3.3 billion francs.

While almorexant met its primary goal in a late-stage clinical study released in 2009, “certain safety observations” were noted that Actelion said needed further evaluation in longer trials. Almorexant’s failure increases the pressure for good results later this year from a study of macitentan, a follow-up to Tracleer, Vontobel’s Weiss said.

To contact the reporter on this story: Dermot Doherty in Geneva at ddoherty9@bloomberg.net

To contact the editor responsible for this story: Phil Serafino at pserafino@bloomberg.net

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