Safety issues force Addex to halt lead drug work

Shares of Switzerland's Addex were suspended after the developer was forced to halt work on its lead therapy -- a potential blockbuster -- after routine monitoring efforts revealed signs of liver problems in the drug group. Addex announced that it had "terminated development of ADX10059 for chronic indications, including long term treatment of gastroesophageal reflux disease and migraine prophylaxis." And with its stock poised to take a nasty tumble, analysts were quick to warn about the impact the news would have on a prospective deal.

"The occurrence of liver function abnormalities in patients receiving the lowest dose, makes future development of this compound difficult, especially for long term use," said Charlotte Keywood, Addex's chief medical officer. Addex officials say they're hard at work trying to understand what prompted the liver problems. And Addex also wasted no time in shifting focus on its pipeline prospects.

"We have cash for operations until the end of 2011 and plan to focus our efforts on development of ADX48621, which has completed Phase I testing and is scheduled to start Phase II testing for the treatment of Parkinson's disease levodopa induced dyskinesia in the fourth quarter of 2010," Vincent Mutel, chief executive officer, says in a statement. "We also will accelerate development of selected programs in discovery and preclinical development and continue to leverage our unique discovery and development platform for allosteric modulator drugs."

ADX10059 has been tapped as a potential billion-dollar earner. And analysts had been looking for the developer to strike a rich deal on a therapy nearing the threshold of Phase III trials. 

"Until the liver toxicity issue for ADX10059 is clarified, it is impossible to value this product," said Piper Jaffray analyst Sam Fazeli. "These safety concerns are likely to deter potential partners, with a deal being crucial for commercial success," said Jefferies analyst Peter Welford.

- here's the Addex release
- here's the Reuters story