CRACK-TARGET 1: ÉTUDE DESCRIPTIVE DE LA SENSIBILISATION COMPORTEMENTALE OBSERVÉE et ATTENTES

This research focuses on behavioral sensitization (BS) a specific behavioural disturbance in crack-cocaine addiction. The primary objective is to observe whether BS can be demonstrated in an ecological setting in crack dependent users by continuous actimetry for 3 weeks.

It is planned to include 20 persons with a current crack-cocaine addiction with a preferential use of rapid administration route (intravenous or smoke), in a care institution: Fernand Widal Hospital.

In the proposed research, the investigators will assess the movements of crack-cocaine dependent users in relation to consumption. They will have to wear continuously for 3 weeks an actimeter. They will also have 3 blood tests trying to identify biomarkers of BS.

Paris region and the French west indies face a specific epidemic of crack-cocaine use, mostly by socially deprived subjects, highly visible in open drug scenes, with little access to the care system. Patients who suffer from crack-cocaine dependence experiment a high rate of medical and a high mortality rate, because this type of cocaine is a short-acting form, used through rapid route of administration (usually smoked or injected).

Nevertheless, despite important uncovered medical needs, they are not often included in clinical trials and there is to date no pharmacological treatment for this severe condition. The investigators identified behavioral disturbances as a key problem in crack-cocaine dependence, as it is the second cause for emergency visits for those patients and a reason to be excluded from addiction care facilities.

Based on preliminary results already gathered by our group, the investigators suggest that behavioral sensitization (BS), an increase of motor response to cocaine after repetitive intermittent use, could be assessed in Humans.

Our goal is therefore to include 20 persons (10 males - 10 females) with a current cocaine use disorder,specifically crack users, with preferential use of rapid administration route (intravenous or smoke), in a care institution: the Fernand Widal Hospital (Assistance Publique - Hôpitaux de Paris). The investigators will assess the movements of crack-cocaine dependent users in relation to consumption. They will have to wear continuously for 3 weeks an actimeter, in the form of a small watch, which collects the level of motor activity throughout the day and night. They will be asked to indicate each moment of crack-cocaine use by pressing the button in the center of the watch. The investigators want to know if certain uses lead to more behavioral problems (especially after periods of cessation).

They will also have 3 blood tests: the investigators want to know if blood proteins, genetic markers passed on by paricipants parents or the expression of proteins in particular situations, could predict this increase in motor effects for small doses of crack-cocaine.

The investigators also want to better understand the needs of crack-cocaine dependent patients towards treatments and their expectations for recovery, by conducting a qualitative study where patients will participate in the definition of treatment aims to increase the efficiency of care

With the project CRACK-TARGET 1 : DETA, the investigators aim at demonstrating the existence of BS in patients with crack dependent subjects. Furthermore, the investigators aim at developing specific, repeatable, easy to access measure of BS using questionnaires and objective actigraphy biomarkers to be used as surrogate endpoints in clinical trials.

Eligibility Criteria:
Inclusion Criteria:

* \> 18 years
* Have a current crack-cocaine use disorder defined as Severe Intensity Use Disorder (6 or more DSM5 criteria), AND preferential use of rapid administration route (intravenous or smoked)
* Self-identified male or female (n=10 males, n=10 females)
* Negative pregnancy test for females and use of effective contraception
* Be affiliated with a social security plan (or PUMA or CSS or AME)
* Sign an informed consent and commit to a 3-week follow-up in the study
* Have a weight greater than 40 kg

Exclusion Criteria:

* • Patient with a psychiatric disorder or symptoms that are not currently stabilized

  * Patient who is a minor or under protective supervision (curatorship or guardianship)
  * Patient in care at the request of a judicial authority (therapeutic injunction, classification with orientation)
  * Pregnant or breastfeeding women
  * Patients who do not speak French or English sufficiently
  * Patients weighing less than 40 kg