8-chloro-6-(2-fluorophenyl)-1-methyl-4H-[1,2,4]triazolo[4,3- a][1,4]benzodiazepine
Recommendation (from TRS)
Substance identification
Valerylfentanyl (N-(1-phenethylpideridin-4-yl)-N-phenylpentanamide) is a synthetic analogue of the opioid fentanyl that is also known as pentanoylfentanyl, pentanyl fentanyl and phenylvaleramide. It has been found in powder and tablet forms.
WHO review history
Valerylfentanyl has not been reviewed previously. A direct critical review was proposed on the basis of information brought to WHO’s attention that valerylfentanyl is manufactured clandestinely, poses a risk to public health and society and has no therapeutic use recognized by any Party.
Similarity to known substances and effects on the central nervous system
Valerylfentanyl is a µ-opioid receptor agonist that is less potent than fentanyl. In view of this mechanism of action, it would be expected to produce the typical range of opioid effects, including analgesia, respiratory depression and sedation.
In a drug discrimination assay in animals predictive of subjective effects in humans, valerylfentanyl produced oxycodone-like effects. It also produces typical opioid effects, such as antinociception, suppresses opioid withdrawal and would therefore be likely to be abused. Both the antinociceptive and discriminative effects were blocked by an opioid antagonist.
Dependence potential
Studies demonstrating the ability of valerylfentanyl to suppress withdrawal in morphine-dependent monkeys suggest that it can produce physical dependence similar to other opioids. No controlled experimental studies pertinent to the dependence potential of valerylfentanyl in humans have been reported.
Actual abuse and/or evidence of likelihood of abuse
In drug discrimination tests in animals predictive of subjective effects in humans, valerylfentanyl produced oxycodone-like effects and would therefore be likely to be abused.
Seized materials containing valerylfentanyl have been reported in a few countries in several regions. Use of valerylfentanyl has been associated with several documented deaths. Cases of driving under the influence of valerylfentanyl have also been documented.
Therapeutic usefulness
Valerylfentanyl is not known to have any therapeutic use.
Recommendation
The available evidence indicates that valerylfentanyl has opioid actions and effects very similar to those of other opioid agonists such as oxycodone and morphine, which are controlled under Schedule I of the 1961 Single Convention on Narcotic Drugs. Valerylfentanyl has no known therapeutic use and could produce substantial harm, including death.
■ Recommendation: The Committee recommended that valerylfentanyl (N-(1-phenethylpideridin-4-yl)-N-phenylpentanamide) be added to Schedule I of the 1961 Single Convention on Narcotic Drugs.