NCT06943573RecruitingPhase 2
Psilocybin-Assisted Therapy for Treatment-Resistant Depression in Bipolar II Disorder
Psilocybin-Assisted Therapy for Treatment-Resistant Depression in Bipolar II Disorder: A Randomized Controlled Trial
Source: ClinicalTrials.gov · Last updated 15 Sept 2026
Brief summary (registry, in English)
This study is a 12-week (in addition to up to 30 days of screening) randomized, double-blind, placebo-controlled, parallel-group trial. The primary objective of this study is to assess the effectiveness, safety, and tolerability of single-dose psilocybin (25 mg)-assisted therapy in comparison to active placebo (1 mg micro-dose) psilocybin-assisted therapy in patients with bipolar II depression who have not responded to adequate trials with at least two first or second-line treatments for bipolar II depression (i.e. quetiapine, lithium, lamotrigine, sertraline, or venlafaxine as monotherapy or adjunctive therapy, or bupropion adjunctive therapy). The active placebo is a substance that looks identical to the study medication but contains less therapeutic ingredients, and thus is less capable of producing the transformative and meaningful aspects of psychedelic experience compared to the 25 mg dose. Participants will have a total of 11 study visits over a period of up to 16 weeks, which includes 5 therapy sessions from trained study therapists.
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 2
- Study type
- Interventional
- Enrollment
- 90 (estimated)
- First submitted
- 1 Apr 2025
- Start date
- Jun 2026
- Primary completion date
- Dec 2028
- Lead sponsor
- Lakshmi N Yatham
- Diseases
- Depression, Bipolar disorder
- NCT number
- NCT06943573
What you commit to
- Study type: Interventional · Phase 2
- Planned participants: 90
- From Jun 2026 to the primary completion date, Dec 2028
- 3 sites in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- You recently (i.e., within the past 8 weeks) began structured psychotherapy (e.g., cognitive-behavioral therapy, interpersonal psychotherapy, family-focused therapy, or interpersonal and social rhythm therapy).
- You have, in the past 6 months, used any psychedelic drugs, including ketamine, LSD, or psilocybin-containing mushrooms.
Other illness
- You have a history of psychotic symptoms.
- You have a history of seizures.
- You have a first-degree relative, such as your parent, sibling, or child, with a diagnosis of a primary psychotic disorder (e.g., schizoaffective disorder, schizophrenia).
- You have a current unstable or inadequately treated medical illness, especially cardiovascular illness, except for the current depression.
- You have a history of nonresponse or intolerance to psilocybin.
- You have a history of non-response to electroconvulsive therapy.
Other
- You recently (i.e., within the past 6 weeks) started taking treatment for your acute bipolar depressive episode.
- You are pregnant or lactating.
Who the study is looking for
- You are male or female aged 19 to 65 years inclusive.
- You have a diagnosis of bipolar disorder type II, and are currently in a major depressive episode.
- You are willing, for the entire duration of the study, to practice highly effective methods of contraception (e.g., contraceptive pills, intrauterine device or system, vasectomy and tubal ligation, or double-barrier methods of contraception) OR agree to completely abstain from heterosexual intercourse. Females who do not have childbearing potential are required to be postmenopausal for at least 1 year before the screening visit (confirmed by an FSH test) OR surgically sterile.
- You have sufficient English language skills to understand, consent to, and comply with study requirements, study visits, and to return to the clinic for follow-up evaluations.
- Your current medications have been at a stable dose for two weeks prior to the dosing visit.
Age in the registry: 19 years to 65 years · Sex: All · Does not accept healthy volunteers
Sites (3)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Department of Psychiatry, University of Ottawa, The Ottawa Hospital Coordinator of this site? Confirm its status | Ottawa | Canada | Not yet recruiting |
| Department of Psychiatry, University of Toronto, University Health Network, Coordinator of this site? Confirm its status | Toronto | Canada | Not yet recruiting |
| Djavad Mowafaghian Centre for Brain Health Coordinator of this site? Confirm its status | Vancouver | Canada | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.