This report has considered the harms and control of 2-methyl-AP-237 and other closely related acyl piperazine opioids.

Following the 66th session of the United Nations Commission on Narcotic Drugs, 2- methyl-AP-237 was added to the relevant Schedule 1 of the Single Convention on Narcotic Drugs of 1961. On 19 June 2023, the UK government commissioned the Advisory Council on the Misuse of Drugs (ACMD) to review the harms and consider control of 2-methyl-AP-237, to comply with our international obligations.

The ACMD has, therefore, written this report which considers the harms and control of 2-methyl-AP-237 and other closely related acyl piperazine opioids. The report also provides recommendations on classification and scheduling following a thorough review of the evidence available.

Specific acyl piperazine opioids that have been detected in international drug markets or in overdose cases, include 2-methyl-AP-237, AP-237 (bucinnazine), AP-238, and para-methyl-AP-237 (Annex A). In addition, more complex, chemically bridged derivatives, such as azaprocin, have been reported in the scientific literature to be significantly more potent than morphine as opioid agonists. It is, therefore, appropriate at this time to consider the group as a whole.