Identification of isotocyanozene at an Australian drug checking service

Novel synthetic opioids of the ‘nitazene’ class, comprised of 2-benzylbenzimidazole opioids and related derivatives, present a growing threat to public health. Most recently emerging in European drug markets in 2019, the nitazene group of drugs has been associated internationally with adverse effects in drug users, overdose clusters, and significant mortality. The variable structure and high potency of many nitazene derivatives, which can exceed that of fentanyl, poses a significant challenge to the public health and early warning systems used to detect and respond to the emergence of new high-risk substances. This report describes the early identification and full analytical characterisation of an emerging nitazene derivative, isotocyanozene (5-cyano isotodesnitazene), in an opioid of uncertain identity presented by a member of the public to an Australian drug checking service. Evaluation of the in vitro μ-opioid receptor biological activity of isotocyanozene (EC 50 = 2.99 nM; E max = 107% of fentanyl activity) and related desnitazene and 5-cyano desnitazene derivatives found that these are potent and efficacious opioids with potential for harm. The study highlights the rapid response possible through engaging drug users with drug checking services as a market monitor and early warning system to alert health services and the broader community to the presence of unexpected, high-risk substances. Integration of well-resourced and supported drug checking services provides a powerful approach to tackle the public health threats associated with novel synthetic opioids and other drugs of concern.