Expert Peer Review No.2 Agenda item 5.8: Phenazepam

Expert Committee on Drug Dependence Thirty-seventh Meeting Geneva, 16-20 November 2015

1. Comments based on the review report

a. Evidence on dependence and abuse potential Available evidence on tolerance and withdrawal is limited to animal studies and no sufficient evidence based data to support dependence and abuse on human studies. However, there has been one reported clinical observational study that shows dependence liability with phenazepam (Ivanetis et al., 2015).

b. Risks to individual and society because of misuse Risks associated to individuals have been well elaborated either when phenazepam is used alone or in combination with other drugs. Effects such as psychomotor impairment, respiratory arrest, psychotic experiences, delirium, overdose and deaths have been reported. Evidence on driving under influence of phenazepam and associated injuries (fatal/nonfatal) including reported incidence of poisoning in children aged 11-14 years has been reported.

c. Magnitude of the problem in countries (misuse, illicit production, smuggling etc) Evidence shows misuse in a number of countries such as UK, Finland, Sweden and U.S.A. Although the drug is manufactured in China as a medicinal drug, it can be easily purchased from the Internet. The illicit market has also been shown in a number of countries such as Finland, Germany, UK, Turkey, Scotland, South Korea, and New Zealand where the drug has been seized in its different forms e.g. powder or tablet, either alone or in combination with other licit/illicit drugs.

d. Need of the substance for medical (including veterinary) practice There is no enough evidence from clinical or multicenter trials on its use in wider medical communities. Its use has been limited to Russia. The fact that phenazepam belongs to the group of , and has similar structure and properties to benzodiazepines such as and ; it can be useful in medical practice. Phenazepam has been used in treatment of neurotic disorders, use disorder, epilepsy, sleep disorder, disorder, and in combination with Haloperidol to treat schizophrenia primarily in Russia where in therapeutic levels have

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Expert Peer Review No.2 Agenda item 5.8: Phenazepam

been shown to be successful.

e. Need of the substance for other purposes (e.g. industrial) No meaningful information to comment on the area.

f. Measures taken by countries to curb misuse Currently interdiction of trafficking by some countries. Legislative measures and law enforcement activities on illegal importation.

g. Impact if this substance if scheduled Likely to have minimal effect due to the fact that there are similarly effective benzodiazepines that are already in the market. Restrictions on availability /access will be crucial to minimize level of use/abuse in the society and inherent harm.

2. Are there absent data that would be determinative for scheduling?

Experience in this use is currently limited to Russia and possibly few EU countries.

3. Other comments or opinions

 Most of the available information on clinical use was available on in Russian language which made it difficult to access.  The long half-life of phenazepam maybe an advantage of low abuse potential in clinical settings and the reported high LD50 is another advantage.  In non-medical settings, it has a high potential for abuse given that the medication is highly potent and can be snorted, inhaled, injected and the tablet crushed.

4. Expert reviewer’s view on scheduling with rationale

The substance - phenazepam can be controlled under schedule IV (UN Convention on Psychotropic Substances, 1971). Its pharmacological profile is similar to other benzodiazepines and has been used therapeutically in medical settings.

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