Clinical TrialObsessive-Compulsive Disorder (OCD)PsilocybinRecruiting

Feasibility, Clinical Effects, and Safety of Psilocybin-assisted Psychotherapy for Treatment-resistant OCD (PAP-OCD)

Open-label, single-group feasibility study (n=10) of two 25 mg psilocybin sessions given two weeks apart with supportive psychotherapy for treatment-resistant OCD.

Target Enrollment
10 participants
Study Type
Phase I interventional
Design
Non-randomized

Detailed Description

Proof-of-concept, open-label single-group trial of 10 adults with treatment-resistant OCD receiving two 25 mg oral psilocybin sessions two weeks apart with psychological support; primary aims are safety and feasibility with Y-BOCS change at Week 3 as a key clinical outcome.

Dosing sessions occur in CAMH’s psychedelic treatment suite, last approximately 5–6 hours, and are supported by two trained therapists; psilocybin is encapsulated (HPMC, PEX010) and participants are discharged with a caregiver after safety evaluation.

Screening includes SCID-5, labs and medication tapering as needed; assessments include Y-BOCS, C-SSRS, AE monitoring, fMRI and neurophysiological measures with follow-ups through 12 weeks after second dosing.

Study Protocol

Preparation

sessions

Dosing

2 sessions
360 min each

Integration

4 sessions

Therapeutic Protocol

support

Study Arms & Interventions

Psilocybin 25 mg

experimental

Two oral 25 mg psilocybin sessions given two weeks apart with supportive psychotherapy.

Interventions

  • Psilocybin25 mg
    via Oral• two sessions• 2 doses total

    Encapsulated HPMC formulation (PEX010); administered with two trained therapists present.

Participants

Ages
18 – 65
Sexes
Male & Female

Inclusion Criteria

  • Adults 18 to 65 years old;
  • Are outpatients;
  • Must be deemed to have capacity to provide informed consent;
  • Must sign and date the informed consent form;
  • Stated willingness to comply with all study procedures;
  • Ability to read and communicate in English, such that their literacy and comprehension is sufficient for understanding the consent form and study questionnaires, as evaluated by study staff obtaining consent;
  • Primary DSM-5 diagnosis of obsessive compulsive disorder (OCD) based on medical records and assessment using the SCID-5 administered at the first screening visit;
  • Participants diagnosed with treatment-resistant OCD defined as individuals with a score of ≥ 16 on the YBOCS and who have not responded to two or more separate pharmacological interventions and one or more trials of cognitive behavioural therapy (CBT);
  • Individuals with an estimated glomerular filtration rate (eGFR) above 40 mL/min/1.73 m2 and all blood work within normal limits as assessed by clinical laboratory tests at Screening (V1);
  • Ability to take oral medication;
  • Individuals who are capable of becoming pregnant: use of highly effective contraception for at least 1 month prior to screening and agreement to use such a method during study participation;
  • Individuals who are willing to and have tapered off current OCD medications for a minimum of 2 weeks prior to Baseline (V2) and whose physician confirms that it is safe for them to do so;
  • Individuals who are willing to and have tapered off current inhibitors of UGT1A9 and UGT1A10, aldehyde dehydrogenase inhibitors (ALDHs) and alcohol dehydrogenase inhibitors (ADHs) for a minimum of 2 weeks prior to Baseline (V2) and for the duration of the study and whose physician confirms that it is safe for them to do so;
  • Agreement to adhere to Lifestyle Considerations throughout study duration.

Exclusion Criteria

  • Pregnant as assessed by a urine pregnancy test at Screening (V1) and Baseline (V2) or individuals that intend to become pregnant during the study or are breastfeeding;
  • Treatment with another investigational drug or other intervention within 30 days of Screening (V1);
  • Have initiated psychotherapy in the preceding 12 weeks prior to Screening (V1);
  • Have a DSM-5 diagnosis of substance use disorder (use of tobacco and prescribed opioids are permitted) within the preceding 6 months;
  • Have active suicidal ideation as determined by the C-SSRS and/or clinical interview. Significant suicide risk is defined by suicidal ideation as endorsed by items 4 or 5 of the C-SSRS;
  • Any DSM-5 lifetime diagnosis of a schizophrenia-spectrum disorder; psychotic disorder (unless substance induced or due to a medical condition), bipolar I or II disorder, paranoid personality disorder, borderline personality disorder, or neurocognitive disorder as determined by medical history and the SCID-5 clinical interview;
  • Any first-degree relative with a diagnosis of schizophrenia-spectrum disorder; psychotic disorder (unless substance-induced or due to a medical condition); or bipolar I or II disorder as determined by the family medical history form and discussions with the participant;
  • Have contraindications to transcranial magnetic stimulation (TMS) as determined by the TASS questionnaire;
  • Have a history of seizures;
  • Are taking anticonvulsants or benzodiazepines (Lorazepam up to 2 mg/day is acceptable);
  • Presence of a relative or absolute contraindication to psilocybin, including a drug allergy, recent stroke history, uncontrolled hypertension, low or labile blood pressure, recent myocardial infarction, cardiac arrhythmia, severe coronary artery disease, or moderate to severe renal or hepatic impairment;
  • Use of classic psychedelic drugs within the previous 12 months;
  • Any other clinically significant physical illness that may interfere with interpretation of the study results or constitute a health risk for the participant.

Study Details

Locations

Centre for Addiction and Mental Health — Toronto, Ontario, Canada

Your Library