TRiP research group


Clinical Trial to investigate the safety and long-term maintenance effects of cannabidiol in remitted or partially remitted early schizophrenia:

Enhancing recovery in early schizophrenia – a multi-center, two-arm, double-blind, randomized clinical trial investigating cannabidiol vs. placebo as an add-on to an individualized antipsychotic treatment

Study code: CBD-ESPRIT

We are currently performing a multi-center clinical trial at the

with support by the German Federal Ministry of Education and Research (BMBF) as part of the ESPRIT consortium.
This double-blind, randomized, controlled study investigates the safety and maintenance effects of cannabidiol vs. placebo as an add-on to a open-label modern, flexible-dose antipsychotic treatment with either amisulpride, aripiprazole, olanzapine, quetiapine, or risperidone in

remitted or partially remitted patients suffering schizophrenia with a diagnosis no older than seven years at time of inclusion in the study.
The study is open for patients fulfilling inclusion criteria and not matching any exclusion criteria subject to the ability to speak either fluently German or English.
Please check, if you fulfil inclusion criteria and that no exclusion criterium is matched. If this is the case, you may CONTACT US if you are willing to participate in the trial. We will then provide further information and may make contact to your nearest study site.

Inclusion criteria:
  • Informed consent given by the subject
  • DSM-IV-TR diagnosis of schizophrenic psychosis (295.10, 295.20, 295.30, 295.90 (American Psychiatric Association)
  • First documented diagnosis of schizophrenia must not be no older than fifteen years
  • Age 18 to 65 years, male or female
  • No or only moderate psychotic symptoms with a maximum initial PANSS score of <75 at baseline
  • Patients must receive a stable oral dose of amisulpride (up to 1200 mg/day), aripiprazole (up to 30 mg/day), olanzapine (up to 20 mg/day), paliperidone (up to 12 mg/day), quetiapine (up to 750 mg/day), or risperidone (up to 10 mg/day) (TAU: treatment as usual) at least two weeks prior to inclusion in the study to ensure that the maximal effect of the previous medication has been received. The initial dose may subsequently be adapted during the trial following clinical judgement of the investigator.
  • Female patients of childbearing potential need to utilise a proper method of contraception.
  • Body Mass Index between 18 and 40.

Exclusion criteria:
  • Lack of accountability (assessed by an independent psychiatrist).
  • History of treatment-resistant schizophrenia, defined as no response to at least two antipsychotics given for a minimum of 6 weeks each in an adequate dosage.
  • Positive urine drug-screening for illicit drugs at screening (except cannabinoids and benzodiazepines).
  • Serious suicidal risk at screening visit (Subject to investigator's and independent psychiatrist's judgement: Poses a serious suicidal or homicidal risk at screening visit or has made a serious suicide attempt within the last 12 months prior to screening visit, or has exhibited homicidal behaviour at anytime during her/his lifetime).
  • Other relevant interferences of axis 1 (e.g. serious depression) according to diagnostic evaluation (MINI) including residual forms of schizophrenia.
  • Pregnancy, as determined through a β-HCG pregnancy test, or lactation.

Please note that we are currently not performing clinical trials investigating cannabidiol in patients with other diagnosis.

Our clinical trial in acute schizophrenia (current notable psychotic symptoms) is currently not recruiting patients (Study code: CBD-FEP).
We will update you on our website if new trials will be started.
Cannabidiol is a compound in clinical testing and its efficacy and safety in schizophrenia needs to be secured. Current data does not allow to draw such a conclusion with sufficient certainty. A use of cannabidiol outside of clinical trials is therefore not provided at our center and currently not recommended!
We completely understand that many patients are seeking new and less side-effect prone drugs for the treatment of their disorder(s) and don't want to wait that long. However, the process of approval and registration of new compounds has to comply to international rules and competent authorities are thereby able to protect patients towards ineffective or even dangerous drugs in particular in maintenance treatment.