Testing the Efficacy of the Cannabis Clinic for Patients With Psychosis (CCP) Intervention for Cannabis Use Reduction/Cessation in Patients With First Episode Psychosis (FEP)

Sponsor
King's College London
Study ID
NCT07245212
Status
Not Yet Recruiting

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Conditions

  • Cannabis Use Disorder
  • First Episode Psychosis (FEP)
  • Psychosis

Eligibility Criteria

Sex
ALL
Age
18 Years - 65 Years
Healthy Volunteers
Not accepted

Interventions

  • CCP Intervention — OTHER
    1. one-to-one weekly sessions: offered both face to face and online to meet the patient preference. Patients can change the meeting modality at any point to suit their needs (e.g. transport difficulties, family commitments, or mental state). The CCP intervention uses a combination of evidence-based psychosocial interventions (PSIs) tailored to each patient's needs. Patients are offered on average 12 (SD 4.2) weeks sessions, for a maximum of 60 minutes. 2. an online PEER group is facilitated by a senior member of CCP staff and moderated by two PEER mentors with lived experience of psychosis and cannabis use.

Study Details

People suffering from psychosis who use cannabis experience more relapses, long and compulsory admissions, with huge costs to the individual, families and health services. The Cannabis Clinic for Psychosis (CCP) was developed to respond to this clinical need. A published review of the CCP's intervention showed its safety and efficacy in supporting people suffering from psychosis with reducing their cannabis use. Nevertheless, for the CCP model of care to be applied widely and benefit a larger clinical population, its intervention needs to be tested in a Randomised Control Trial (RCT). The proposed CCP RCT is a waiting list randomised controlled trial that aims to evaluate the clinical efficacy of the existing CCP intervention. Participants will be adults currently under the care of South London and Maudsley (SLaM) Early Intervention Teams for first onset psychosis, who are dependent on cannabis and who express an intention to reduce or stop their use. The RCT primary outcome will measure changes in all participants' cannabis use. Participants will be randomised to either the intervention group or the waiting list control group receiving Treatment As Usual (TAU). The CCP intervention comprises 12 weekly (+/- 4 weeks) one-to-one sessions, with optional participation in a weekly online peer group. Sessions are delivered by trained clinicians and include evidence-based psychosocial techniques, including Motivational Interviewing (MI), Cognitive Behavioural Therapy (CBT), SMART goal settings and support for co-occurring tobacco use. The treatment is non-pharmacological and administered via participant-led approach that accommodates online or face-to-face sessions to meet the patient preference. Qualitative data from the recent CCP proof of concept paper indicate that the flexibility in allowing patients choice on the session's modality (online/face to face, hybrid) increased and maintained engagement. The study is fully funded by the Maudsley Charity and due to last 30 months from the start of recruitment.

Key Dates

First listed
Nov 24, 2025
Start date
Dec 1, 2025
Status verified
Sep 2025
Primary completion
Nov 30, 2028
Completion
Nov 30, 2028

Study Design

Enrollment
80 participants (estimated)
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT

Arms

  • Experimental: Cannabis for Psychosis Intervention + Treatment as Usual
    The CCP intervention consists of two main components: 1. one-to-one weekly sessions: offered both face to face and online to meet the patient preference. Patients can change the meeting modality at any point to suit their needs (e.g. transport difficulties, family commitments, or mental state). The CCP intervention uses a combination of evidence-based psychosocial interventions (PSIs) tailored to each patient's needs. Patients are offered on average 12 (SD 4.2) weeks sessions, for a maximum of 60 minutes 2. an online PEER group is facilitated by a senior member of CCP staff and moderated by two PEER mentors with lived experience of psychosis and cannabis use.
  • No Intervention: Treatment as Usual / Waiting List
    Participants continue Treatment as Usual from their clinical team while on a 16-week waiting list for the CCP intervention.

Primary Outcome Measure

Cannabis Use Disorders Identification Test-Revised score (CUDIT-R) [ Time Frame: Measured at a baseline assessment and 16 weeks post-randomisation. ]

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