Rewards for Cannabis Abstinence-study (RECAB)

Parnassia Addiction Research Centre

Status: Enrolling

Conditions: Cannabis Use Disorder

Treatments: Behavioral: Standard Outpatient Cognitive Behavioural Therapy (CBT); Behavioral: Abstinence-focused Contingency Management (CM) - stand alone

Study type: Interventional

Funder types: Other

Identifiers

NCT05836207

10390012110082

Details and patient eligibility

About

The goal of this clinical trial is to investigate the (cost-)effectiveness of contingency management (CM) compared with Cognitive Behavioural Therapy (CBT) for the treatment of cannabis use disorder (CUD) in youth (16-22 years).

The main questions it aims to answer are:

• What is the efficacy of 12 weeks outpatient CM versus CBT in youths with a CUD, in terms of cannabis abstinence during the intervention period?
• What is the long-term efficacy of CM versus CBT at 6- and 12-months follow-up (FU)?
• What is the cost-effectiveness of CM versus CBT at 12-months FU from a societal perspective?

Study hypotheses are:

1. CM will result in more cannabis-abstinent days than CBT during the intervention; 2. CM is more effective and cost-effective than CBT at 12 months follow-up.

Eligible patients (n=154) will be randomly assigned to either 12 weeks of outpatient CM or CBT. Assessments are conducted by trained research-assistants at baseline, after 6, 12, 26 and 52 weeks, and twice-weekly during treatment and consist of questionnaires, a computer task and collection of urine samples. Primary endpoint is the number of biochemically verified cannabis abstinent days in the 12-week treatment period. Key secondary endpoint: Treatment response: 50% or more reduction in cannabis use days in the past 4 weeks, compared with baseline.

The primary outcome will be modelled in the intention-to-treat population in a (negative binomial) regression analysis with treatment group as independent variable and stratification variables as covariates.

Cost-effectiveness and cost-utility analysis (CEA; CUA) will be performed from a societal perspective. CEA: Treatment response is the central clinical endpoint for calculations of incremental costs per responder. CUA: Incremental costs per QALY (based on EuroQoL).

Enrollment: 154 estimated patients

Sex: All

Ages: 16 to 22 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Youths (16-22 years) seeking treatment for a primary CUD
• Regular cannabis use (≥14 days) in past 4 weeks
• Intention to cease cannabis use during intervention
• Able and willing to attend the treatment center and submit urine samples under supervision twice-weekly
• Informed consent.

Exclusion criteria

• Health contra-indications (e.g., acute psychosis/suicidality)
• Insufficient Dutch language.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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154 participants in 2 patient groups

Abstinence-focused Contingency Management (CM)

Experimental group

Description:

Youths receive 12 weeks of outpatient abstinence-focused CM consisting of providing incentives for cannabis abstinence, based on twice-weekly rapid test urinalysis.

Treatment:

Behavioral: Abstinence-focused Contingency Management (CM) - stand alone

Cognitive Behavioural Therapy (CBT)

Active Comparator group

Description:

Youths receive 12 weeks of outpatient usual care CBT consisting of once-weekly 60-minute sessions according to the standard CBT youth protocol by a trained psychologist.

Treatment:

Behavioral: Standard Outpatient Cognitive Behavioural Therapy (CBT)