Updated on 1/19/2016 at 9:24 AM EST.
Clinical trials are an essential part of the drug development process. In order to get life-improving and life-saving medicines to patients, they first have to go through an extensive series of tests. Even before a drug makes it to Phase 1 testing, where its safety, dosage amount, and side effects are tested in a small group of humans, it will undergo testing in animals. As a result, it is not common for a medicine undergoing clinical tests to have a very serious adverse effect on a human. This makes you wonder what happened to a group of patients involved in a clinical study in Rennes, France.
According to news reports, a drug undergoing testing in a French clinic has left one person dead, two others with what may be permanent brain damage, and and two others critically ill. The drug has thus far been unnamed, but it appears to have been produced by the Portuguese company Bial. The French health minister has stated the drug acted on natural receptors found in the body known as endocannibinoids, which regulate mood and appetite. It did not contain cannabis or anything derived from it, as was originally reported. All six trial participants were administered the doses simultaneously.
The trial was being performed at Biotrial, a French-based firm that was formed in 1989 and has conducted thousands of trials. A message on the company’s website stated that they are working with health authorities to understand the cause of the accident, while extending thoughts to the patients and their families. Bial has disclosed the drug was a FAAH (fatty acid amide hydrolase) inhibitor, which is an enzyme produced in the brain and elsewhere that breaks down neurotransmitters called endocannabinoids. Two scientists from the Nottingham Medical School who have worked with FAAH tried over the weekend to try and identify the drug by examining a list of drugs Bial currently has in its pipeline. They believe the culprit is one identified by the codename BIA 10-2474. That same codename appeared on a recruitment form that was given to a volunteer, which was published in a French newspaper. Little more is known about it, and there does not appear to be any entry for it in clinical trial registries.
The French health ministry is reporting the six patients were all in good health prior to taking the oral medicine, which was administered to 90 volunteers. The trial recruited 128 individuals, and the remaining participants received a placebo. Health minister Marisol Touraine, describing the situation as a very serious accident, noted the patients were taking part in a trial in Brittany, Rennes involving a medicine developed by a “European laboratory”, refusing to comment further until additional information became available. She has also asked the Inspector General of Social Affairs to lead an investigation into the circumstances around the trial, which has obviously been suspended. She notes the drug had been tested on animals, including chimpanzees. France's National Agency for Medicine and Health Products Safety approved the trial on in June 2015.
One thing we do know is that the trial was a Phase 1 clinical study that included 90 healthy volunteers. Regulations that oversee all clinical trials in Europe do attempt to minimize the risk associated with trials, but there is always a risk involved with administering an unapproved medicine to humans. At this time the chief neuroscientist at the hospital where the patients are being treated has said there is no known antidote for the drug.
The drug, administered to men between the ages of 28 and 49, was intended to treat mood disorders such as anxiety. While the men were administered varying doses, the patients who are hospitalized were taking the drug “regularly”.
While safety issues like this are rare, they are not unheard of. In 2006, a clinical trial in London left six men ill. All were taking part in a study testing a drug designed to fight auto-immune disease and leukemia. Within hours of taking the drug TGN1412, all experienced a serious reaction, were admitted to intensive care, and had to be treated for organ failure. Two became critically ill, with one eventually losing all of his fingers and toes. All were told they would have a higher risk of developing cancers or auto-immune diseases.
This of course led many to wonder about the future of trials, and whether the situation could happen again. The Duff Report, written in response to the TGN1412 trial, noted the medicine should have been tested in one person at a time. It also helped to put additional safety measures in place. The Medicines and Health Products Regulatory Agency (MHRA) now requires committees to look at pre-clinical data to determine the proper initial dose, and rules are in place to stop the trial if unintended reactions occur.
However, since patients can fall ill immediately after being administered a medication, certain risks will still exist.
The company that manufactured TGN1412, TeGenero Immuno Therapeutics, later went bankrupt. However the drug was later purchased by a Russian investor and renamed TABO8. TheraMAB, a Russian biotech company, then conducted a new trial of the drug in a much lower dose. A later Phase 2 study was started in patients with Rheumatoid Arthritis.