LONDON British pharmaceutical group GlaxoSmithKline Plc said vercirnon, a drug it was developing to treat Crohn's disease and licensed from ChemoCentryx, had failed in a late-stage clinical trial.
The medicine, which GSK licensed from the California-based company in 2010, did not improve the incidence of adverse events in patients when measured against a placebo, GSK said on Friday, and there was a trend for overall adverse events to increase as dosage levels increased.
The trial failure wiped as much as $242 million, or nearly half, from ChemoCentryx's value. Its shares were trading down 36 percent at $7.47 at 1438 GMT. GSK's shares were up 0.3 percent at 1,672 pence, underperforming a 0.7 percent stronger FTSE 100 index.
"The results from the SHIELD-1 study are clearly disappointing but we are committed to further explore the data to determine the way forward to help patients with this chronic debilitating gastrointestinal disease," said Paul-Peter Tak, senior vice president of GSK's immuno-inflammation research and development.
The company said new recruitment and dosing in the ongoing clinical trial had been suspended pending further review of the results.
Vercirnon, a type of drug called an antagonist, was being developed by GSK for the potential treatment of inflammatory bowel diseases, such Crohn's disease, a condition with symptoms such as persistent diarrhea and abdominal pain.
(Reporting by Paul Sandle; editing by David Evans)