AB-FUBINACA

Substance identification
AB-FUBINACA (1-amino-3-methyl-1-oxobutan-2-yl]-1-[(4-fluorophenyl) methyl]indazole-3-carboxamide) is a synthetic cannabinoid. It has been found sprayed on plant material for smoking.

WHO review history
AB-FUBINACA has not been reviewed previously. A critical review was proposed on the basis of information brought to WHO’s attention that AB-FUBINACA was 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
AB-FUBINACA is a synthetic cannabinoid with a profile of centrally mediated effects similar to those of other synthetic cannabinoids. It is a potent full agonist at CB1 receptors and binds to CB2 receptors. It is a structural analogue of ADB- FUBINACA, which is currently controlled under the Convention on Psychotropic Substances of 1971.

In preclinical studies in mice, AB-FUBINACA produced pharmacological effects characteristic of psychoactive cannabinoids, including suppression of locomotor activity, antinociception, hypothermia and catalepsy. These effects were reversed by a CB1 antagonist. AB-FUBINACA also impaired coordination and balance and produced neurological signs such as convulsions, hyperreflexia, myoclonus, sensorimotor alterations and spontaneous aggressiveness.

Little information is available on its effects on the human central nervous system. In a case report in which AB-FUBINACA was used with ADB- FUBINACA, the clinical features of intoxication included confusion, agitation, somnolence, hypertension and tachycardia, similar to those with other synthetic cannabinoid receptor agonists.

Dependence potential
No controlled experimental studies of the dependence potential of AB- FUBINACA in humans or animals were available. In view of its action as a full CB1 agonist in the central nervous system, however, AB-FUBINACA would be expected to produce dependence in a manner similar to other synthetic cannabinoids.

Actual abuse and/or evidence of likelihood of abuse
In tests of drug discrimination in animals predictive of subjective effects in humans, AB-FUBINACA had typical cannabinoid-like effects and would therefore be likely to be abused.

Many cases of intoxication with AB-FUBINACA have been reported. At least one death has been reported in which AB-FUBINACA was the only synthetic cannabinoid detected.

AB-FUBINACA has been seized in a number of countries in various regions.

Therapeutic usefulness
AB- FUBINACA is not known to have any therapeutic use.

Recommendation
AB-FUBINACA is a synthetic cannabinoid receptor agonist with a mode of action that suggests the likelihood of dependence and abuse and similar ill- effects to other synthetic cannabinoids. Its use has been associated with a wide range of severe adverse effects, including death. The effects are similar to those of other synthetic cannabinoids that have the same mechanism of action as AB- FUBINACA and which are in Schedule II of the Convention on Psychotropic Substances of 1971. AB-FUBINACA has no therapeutic use.

■ Recommendation: The Committee recommended that AB-FUBIN- ACA (1-amino-3-methyl-1-oxobutan-2-yl]-1-[(4-fluorophenyl)me- thyl]indazole-3-carboxamide) be added to Schedule II of the Con- vention on Psychotropic Substances of 1971.