Researchers stress that no conclusions can be drawn yet about the safety of cannabis and cannabinoid research.
A drug study that killed 1 person and left 5 others hospitalized did not contain cannabis or cannabinoids as was previously reported.
Bial, a pharmaceutical company located in Portugal, designed an FAAH inhibitor that was supposed to act on the human endocannabinoid system as an anxiety treatment and possible painkiller.
A phase 1 trial enrolled 128 participants between the ages of 18 to 55, of which 90 patients were given the drug at varying dosage levels and the rest received a placebo.
Participants began taking the drug on January 7, 2016, as the first patients began to get sick on January 10, CNN reported.
"Without adequate information it is impossible to advance any realistic theory about causes of toxicity," said University of California-Irvine School of Medicine Professor and Editor-in-Chief of Cannabis and Cannabinoid Research, Daniele Piomelli, PhD. "Several structurally different FAAH inhibitors have been previously tested for human safety in rigorous phase 1 clinical trials. These include compounds from Sanofi, Pfizer, Merck, Johnson and Johnson, and others. All these FAAH inhibitors were shown to be safe in humans."
Since other FAAH inhibitors have been deemed safe, it’s believed that the interaction of the Bial compound with FAAH were unlikely the cause of these results. Dr. Piomelli, believes that the Bial compound most likely interacted with an unknown protein, which was the cause of the toxic results or a previous toxic impurity in the drug.
"While we can tentatively exclude a class effect at this point, we cannot pin-point which other target might be responsible for the toxicity of the Bial compound," Dr. Piomelli said.
Furthermore, since there is only a small amount of information that is publicly drawn, researchers are unable to draw any conclusions about the safety and efficiency of future cannabis and research.