Image copyright Reuters Image caption The chief neuroscientist at the hospital in Rennes said there was no known antidote to the drug 
 
 One man is brain-dead and another five people are in hospital after an experimental drug was administered to 90 people in a French clinical trial. 
 
 There is no known antidote to the drug, the chief neuroscientist at the hospital in Rennes said. 
 
 Of the six men in hospital, three could have permanent brain damage, Gilles Edan added. 
 
 Reports that the drug is a cannabis-based painkiller have been denied by the health ministry. 
 
 A fifth man is suffering from neurological problems and a sixth man is being monitored but is not in a critical condition, Mr Edan said. 
 
 The trial, which involved taking the drug orally and has now been suspended, was conducted by a private laboratory in Rennes. 
 
 The experimental drug was manufactured by the Portuguese company Bial. 
 
 All those who volunteered for the trial have been recalled and the Paris prosecutor's office has opened an investigation. 
 
 Health Minister Marisol Touraine pledged to "get to the bottom... of this tragic accident". 
 
 "I was overwhelmed by their distress" she told reporters. "Their lives have been brutally turned upside down". 
 
 Analysis 
 
 By James Gallagher, health editor, BBC News website 
 
 This is the bitter price of the new medicines we take for granted. Testing such experimental drugs, at the cutting edge of science, can never be completely risk-free. 
 
 The safety and effectiveness of these drugs are rigorously tested in animals. The risks are low but there must still be a leap of faith when they are tried in people for the first time. 
 
 This trial has been taking place since July without such major events being reported. Generally in Phase I trials the dose is increased slowly over time, which could be why the side-effects are appearing now. 
 
 The hospitalised men started taking the drug regularly on 7 January and began showing severe side-effects three days later. 
 
 Three of the volunteers are now facing a lifetime of disability in this "accident of exceptional gravity". 
 
 It is a high price to pay, but thousands of people do safely take part in similar trials each year. 
 
 The trial was conducted by Biotrial, a French-based company with an international reputation which has carried out thousands of trials since it was set up in 1989. 
 
 In a message on its website, the company said that "serious adverse events related to the test drug" had occurred. 
 
 The company insisted that "international regulations and Biotrial's procedures were followed at every stage". 
 
 According to the health ministry, the adverse effects occurred on Thursday. 
 
 Clinical trials 
 
 Trials typically have three phases to assess a new medicine for safety and effectiveness 
 
 Phase I tests for safety. A small number of people, sometimes healthy, and sometimes with a medical condition, are given a tiny dose of the drug under careful supervision, not to test if the drug works, but in order to check for any side effects 
 
 Phase II sees the drug given to people who have a medical condition to see if it does indeed help them 
 
 Phase III trials are only for medicines or devices that have already passed the first two stages, and involve them being compared to existing treatments or a placebo. The trials often last a year or more, involving several thousand patients 
 
 Has drug trial safety improved? 
 
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 Why some new drugs cost so much 
 
 The study was a Phase I clinical trial, in which healthy volunteers take the medication to evaluate the safety of its use, the ministry said. 
 
 Before any new medicine can be given to patients, detailed information about how it works and how safe it is must be collected. 
 
 Image copyright AFP Image caption Health Minister Marisol Touraine travelled to Rennes to monitor the incident 
 
 Clinical trials are the key to getting that data - and without volunteers to take part in the trials, there would be no new treatments for serious diseases such as cancer, multiple sclerosis and arthritis. 
 
 Every year around the world thousands of people take part in clinical trials but incidents like this are very rare, the BBC's Hugh Schofield reports from Paris. 
 
 New EU regulations to speed up clinical drug trials and streamline testing procedures across the 28-nation bloc are due to take effect in 2018. ||||| One person is brain dead and five others are seriously ill after taking part in a drug trial for Portuguese pharmaceutical firm Bial at a clinic in north-west France. 
 
 The French health ministry said the six male patients aged 28 to 49 had been in good health until taking the oral medication. They started taking the drug on 7 January. One person started feeling ill on Sunday and the other five afterwards. The brain dead volunteer was admitted to hospital in Rennes on Monday. Other patients went in on Wednesday and Thursday. 
 
 Pierre-Gilles Edan, head of the hospital’s neurology department, said one man was brain dead, three others were suffering a “handicap that could be irreversible” and another had neurological problems. The sixth volunteer had no symptoms but was being monitored. 
 
 The French health minister, Marisol Touraine, said 90 people in total had taken part in the trial and received some dosage of the drug; others had taken a placebo. All trials on the drug have been suspended and all volunteers who have taken part in the trial are being called back. 
 
 The ministry said the test was carried out by the Biotrial clinic for Bial, which “specialised in carrying out clinical trials”. 
 
 The trial was intended to test for side-effects of the new drug but all trials at the clinic have been suspended and the French state prosecutor has opened an inquiry. 
 
 Touraine said the drug was a so-called FAAH inhibitor meant to act on the body’s endocannabinoid system, which deals with pain. Earlier reports suggested that the drug contained cannabinoids, an active ingredient found in cannabis plants, but the minister said it did not contain the drug or any derivatives of it. 
 
 Touraine said the study was a phase one clinical trial, in which healthy volunteers take the medication to “evaluate the safety of its use, tolerance and pharmacological profile of the molecule”. 
 
 Medical trials typically have three phases to assess a new drug or device for safety and effectiveness. Phase one entails a small group of volunteers and focuses only on safety. Phase two and three are progressively larger trials to assess the drug’s effectiveness, although safety remains paramount. 
 
 Testing had already been carried out on animals, including chimpanzees, starting in July, Touraine said. 
 
 Bial said it was committed to ensuring the wellbeing of test participants and was working with authorities to discover the cause of the injuries, adding that the clinical trial had been approved by French regulators. 
 
 Every year, thousands of volunteers, often students looking to make extra money, take part in such trials. Mishaps are relatively rare, but in 2006 six men were treated for organ failure in London after taking part in a clinical trial into a drug developed to fight auto-immune disease and leukaemia. 
 
 The men now apparently have a higher risk of cancer and autoimmune diseases tied to their exposure to the experimental drug. 
 
 Dr Ben Whalley, a neuropharmacology professor at Britain’s University of Reading, said standardised regulations for clinical trials were “largely the same” throughout Europe. “However, like any safeguard, these minimise risk rather than abolish it,” Whalley said. “There is an inherent risk in exposing people to any new compound.” 
 
 Agence France-Presse contributed to this story 
 
 ||||| PARIS (AP) — Rennes chief neurosurgeon Gilles Edan says three of the 6 men hospitalized over a botched clinical drug trial in France could have "irreversible" brain damage. 
 
 Speaking Friday at a press conference in the western French city of Rennes, Edan said one man is brain dead and four others have "neurological problems" — of which three could have permanent damage. Another man is being kept in the hospital, but is in a less critical condition. 
 
 Health Minister Marisol Touraine says all the men were healthy before they volunteered for the drug trial. She urged calm and said no drug currently on the market was implicated in the failed trial.
– A drug trial in France has gone horribly wrong, leaving one healthy volunteer brain-dead; three other men may have suffered irreversible brain damage, another has "neurological problems," and a sixth is hospitalized with less severe problems, reports AP. Details on what happened, including what drug was being tested and its manufacturer, remain under wraps. One thing that is known: No treatment is available. Early reports in France suggested it was a cannabis-based painkiller, reports the Guardian, but the health ministry has denied that. The AP describes it as some kind of "painkiller compound." Testing was being conducted by the French company Biotrial, a veteran player in the industry, at a clinic in Rennes. All 90 volunteers who took the drug were healthy before the trial started, reports the BBC. Those hospitalized range in age from 28 to 49 and began taking the drug on Jan. 7. Health Minister Marisol Touraine promised to "get to the bottom... of this tragic accident" and said she's been "overwhelmed" by the tragic turn for participants. "Their lives have been brutally turned upside down." The study had been in phase one, in which volunteers take the drug orally to evaluate its effectiveness and side effects. A message on Biotrial's website states that "serious adverse events" occurred and says that international regulations "were followed at every stage throughout the trial, in particular the emergency procedures for the transfer of subjects to the hospital."