By email only ACMD@homeoffice.gov.uk

29 January 2025

Dear Owen and Simon,

Fifth addendum to Advisory Council on the Misuse of Drugs (ACMD) report on the use and harms of 2-benzyl benzimidazole (‘nitazene’) and piperidine benzimidazolone (‘brorphine-like’) opioids.

I would like to thank the ACMD for the recent advice dated 8 November 2024 on the fifth addendum to the generic definition on 2-benzyl benzimidazole opioids (nitazenes).

As you are aware, following the advice from the ACMD published on 5 April 2024, we have introduced a generic definition of nitazenes as Class A drugs under the Misuse of Drugs Act 1971 (‘MDA 1971’). We have also added this generic definition of nitazenes to Schedule 1 to the Misuse of Drugs Regulations 2001 (‘MDR 2001’) and designated it under the Misuse of Drugs (Designation) (England, Wales and Scotland) Order 2015 (‘2015 Order’). These changes came into force on 15 January and follow the other 14 named nitazenes controls which were introduced on 20 March 2024.

I would like to thank the ACMD, especially the Novel Psychoactive Substances (NPS) Committee for its commendable alertness to new synthetic opioids and the pace at which it provides its recommendations on this issue. As you know, this Government is committed to remain as proactive as possible to the threat of emerging synthetic opioids.

I have noted the ACMD advice to update the generic definition of nitazenes to capture carbamoyl derivatives as well as a further 2-benzyl benzimidazole compound, aminoisotonitazene, which has recently been identified in the UK.

I formally accept the ACMD fifth addendum recommendation and will seek to consult stakeholders, including academia and the chemical and pharmaceutical industries on the following amendment:

Any compound (not being a compound for the time being specified in sub- paragraph (a) above), with a maximum molecular mass of 500 atomic mass units, structurally derived from 2-(2-benzyl-benzimidazol-1-yl)ethanamine by modification in any of the following ways, that is to say:

(i) By substitution at the nitrogen of the ethanamine to any extent by alkyl substituents containing up to three carbon atoms or alkenyl substituents containing up to three carbon atoms or by inclusion of the nitrogen atom (and no other atoms of the side chain) in a cyclic structure.

(ii) By substitution in the phenyl ring of the benzyl system to any extent by alkyl or haloalkyl containing up to six carbon atoms, alkoxy or haloalkoxy containing up to five carbon atoms, acetyloxy, hydroxy, cyano, halogen, thioalkyl containing up to five carbon atoms or alkylsulphonyl containing up to five carbon atoms.

(iii) By substitution at the 5- or 6- positions of the benzimidazole system by nitro, acetyl, amino, cyano, methoxy, trifluoromethyl, trifluoromethoxy or halogen substituents.

(iv) By substitution at the benzylic carbon by a methyl group or by a carbamoyl group.

(v) By replacement of the benzylic carbon by a nitrogen, oxygen or sulphur atom.

(vi) By substitution in the phenyl ring of the benzyl system by an ethoxy group linked back to the phenyl ring to form a dihydrobenzofuran structure.

(vii) By replacement of the phenyl ring of the benzyl system by methylenedioxyphenyl.

Following this consultation, we will include this amended generic definition of nitazenes as a Class A drug under the MDA 1971, as well as placing it in Schedule 1 of the MDR 2001 and designating it under the 2015 Order.

Yours sincerely,

Dame Diana Johnson

Minister for Policing, Fire and Crime Prevention