One person is in a coma and five other seriously ill after taking a medical trial for an unnamed European laboratory to test a new drug, French health ministry said.
According to The Guardian, the ministry did not say what the medicine was intended to be used for, but said the six patients, one of whom was in a coma, had been in good health until taking the oral medication.
A private establishment, specialised in carrying out clinical trials, carried out the test, said the ministry.
All trials on the drug at the clinic in Rennes in Brittany have now been suspended. The French state prosecutor has opened an inquiry.