The efficacy of psilocybin assisted psychotherapy... — Clinical Trial Details

Open-label, non-randomised single-arm pilot enrolling adults with treatment-resistant OCD, BDD or AN to receive two oral psilocybin doses (25 mg) four weeks apart paired with structured psychotherapy.

Therapy delivered by a therapist dyad includes preparation (1–2 sessions, ≈3 hours total), non-directive support during 8-hour dosing sessions, and two integration sessions after each dose (four total); sessions predominantly face-to-face with limited online option for the second integration.

Primary outcomes assess disorder-specific symptom severity (YBOCS, BDD-YBOCS, EDE) at baseline and 8 weeks post-baseline with safety monitoring per protocol.

Participants

Ages

18 – 65

Sexes

Male & Female

BMI

Psychosis History

Excluded

Inclusion Criteria

i) Adults aged 18 to 65 years.
ii) Primary diagnosis of OCD, BDD or AN according to DSM-5, determined by SCID-5, the BDD Diagnostic Module (BDD-DM) and Eating Disorder Examination (EDE).
iii) Moderate to severe symptom severity: YBOCS ≥18 for OCD; BDD-YBOCS ≥20 for BDD; score ≥3 on the shape and/or weight subscales of the EDE for AN.
iv) Treatment resistance: ≥1 year illness with continuing symptoms for ≥6 months despite adequate engagement in conventional interventions defined per disorder (OCD: SSRI course and at least one course CBT including ERP; BDD: two courses psychotherapy and/or pharmacology including at least one CBT; AN: two courses psychotherapy and/or pharmacology including in-patient/day program or >1 year extensive therapy or multidisciplinary care; adequate SSRI/SNRI course where applicable).
v) Illness duration ≥1 year.
vi) Absence of delusionality for OCD/BDD indicated by insight item score <3 on YBOCS/BDD-YBOCS.
vii) Absence of mania symptoms (only minor). viii) Sufficient cognitive ability (WASI) and demonstrated understanding of consent procedures.

Exclusion Criteria

Psychiatric exclusions:
i) Lifetime history of serious suicide attempts requiring hospitalisation or current suicidal ideation with intent warranting immediate hospitalisation.
ii) Current or past history of psychosis; DSM-5 Schizophrenia, Psychotic Disorder (unless substance-induced or due to medical condition), Bipolar I/II or Mania.
iii) First-degree relative with diagnosed Schizophrenia, Psychotic Disorder (unless substance-induced or due to medical condition), Bipolar I/II or Mania.
iv) Significant neurodevelopmental disorder (e.g., ADHD, autism, unremitting Tourette’s) impacting therapeutic effect.
v) Current DSM-5 Dissociative Disorder, Bulimia Nervosa, or significant personality disorder judged incompatible with rapport or safe exposure.
vi) Personal or situational factors likely to interfere with participation (e.g., lacking social support, unstable housing, ongoing trauma).
vii) Complex cases from childhood trauma or other factors as judged by clinicians.
General medical exclusions:
i) Any disorder with known CNS involvement or disease, including seizures.
ii) Hepatic dysfunction: GGT >3×ULN; AST >3×ULN; ALT >3×ULN; Total bilirubin >3.0 mg/dL.
iii) Conditions raising risk for hypercalcaemia, Cushing's, hypoglycaemia, SIADH, carcinoid syndrome.
iv) Cardiovascular conditions: uncontrolled hypertension (systolic >140 or diastolic >90), angina, clinically significant ECG abnormality (e.g., atrial fibrillation), TIA in last 6 months, stroke or cerebrovascular disease, peripheral or pulmonary vascular disease; QTc >440 ms men, >470 ms women.
v) Renal insufficiency (CrCl <40 mL/min by Cockcroft-Gault).
vi) Insulin-dependent diabetes; oral hypoglycaemics allowed only if no history of hypoglycaemia.
vii) Females who are pregnant, breastfeeding, trying to become pregnant, or become pregnant during study.
viii) Untreated or refractory hypothyroidism.
ix) Weight <40 kg or BMI <13 kg/m2 (text contained garbled BMI cutoff; exclusion for very low BMI applies).
x) Certain long-acting opioids timing allowances as specified in protocol.
xi) Macro-dose psychedelic use within past 12 months or >10 macro-doses lifetime.
xii) Micro-dose use within past 6 months.
xiii) Contraindicated medications (SSRIs, SNRIs, MAOIs) unless appropriately managed/tapered.
xiv) Current/past 5 years of alcohol or drug dependence (excluding caffeine/nicotine).
xv) Use of illicit drugs or alcohol within 2 days prior to dosing.
xvi) Use of potent metabolic inducers/inhibitors (listed in protocol).
xvii) Need for drugs with low therapeutic index within 12 hours post-psilocybin.
xviii) Significant uncorrected visual impairment.

Company

Product

Legal

The efficacy of psilocybin assisted psychotherapy (PAP) for treatment resistant obsessive-compulsive disorder (OCD), body dysmorphic disorder (BDD), and anorexia nervosa (AN); a pilot, single-arm basket trial

Detailed Description

Study Protocol

Preparation

Locations

Dosing

Integration

Therapeutic Protocol

Study Arms & Interventions

Psilocybin PAP

Interventions

Participants

Inclusion Criteria

Exclusion Criteria

Study Details