(Photo: AP Photo/David Vincent)

One person has been left brain dead and five others are in serious condition after taking part in the clinical trial of an experimental painkiller made by Portuguese drug company Bial, the French Health Ministry said on Friday.



The medicine involved works by targeting the body’s pain-controlling endocannabinoid system, which is also responsible for the human response to cannabis.

The ministry said the six volunteers in Rennes, in western France, had been in good health until taking the oral medication at a private facility that specializes in carrying out clinical trials.

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The brain-dead volunteer was admitted to hospital in Rennes on Monday. Other patients went in on Wednesday and Thursday.

The volunteers are all men aged 28 to 49, French Health Minister Marisol Touraine told a news conference. They started taking the drug on Jan 7. One person started feeling ill on Sunday and the other five afterwards.

The chief neuroscientist at the hospital in Rennes says there’s no known antidote to the experimental drug they were testing.



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Professor Gilles Edan, the chief neuroscientist at Rennes Hospital, spoke at a press conference Friday in the western French city.



Touraine also told reporters that all those hospitalized were healthy men when the trial began on Jan. 7. She said one man who has now been classified as brain dead was admitted to the hospital on Sunday.

The French prosecutor’s office has opened an investigation into what the Health Ministry is calling a “serious accident during a clinical test” at the Biotrial laboratory in Rennes.

Additional reporting by the AP.

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