Inhaled DMT for Major Depressive Disorder
Randomized, Double-Blind, Placebo-Controlled Phase IIb Trial of Inhaled N,N-Dimethyltryptamine (DMT) for Major Depressive Disorder
Universidade Federal do Rio Grande do Norte
140 participants
Aug 1, 2026
INTERVENTIONAL
Conditions
Summary
This Phase 2b, randomized, double-blind, active-controlled clinical trial will evaluate the efficacy and safety of inhaled N,N-dimethyltryptamine (DMT) in adults with Major Depressive Disorder (MDD). The study will test whether inhaled DMT can rapidly reduce depressive symptoms and suicide risk compared with a low-dose active comparator. A total of 140 participants will be randomized 1:1 to receive either 15 mg followed 1 hour later by 60 mg of inhaled DMT, or 1 mg followed 1 hour later by 4 mg of inhaled DMT. Participants who do not achieve remission at Day 7 will enter an open-label extension and receive a high-dose DMT session on Day 14 (±3 days). All participants will be followed for up to 12 months to evaluate the durability of response, safety, functioning, and quality of life.
Eligibility
Inclusion Criteria7
- years or older, capable of making decisions, and able to provide informed consent.
- Major Depressive Disorder (MDD) according to DSM-5 criteria
- Current depressive episode of moderate to severe intensity
- Episode duration of at least two weeks
- Baseline MADRS score ≥ 20
- No treatment changes (including antidepressants) in the 4 weeks prior to the study
- Abstain from psychedelics ≥14 days before dosing (D0) and during the 12-month follow-up
Exclusion Criteria16
- Major cardiac, hepatic, or renal disease; unstable cardiovascular conditions
- Uncontrolled hypertension, QTc prolongation, arrhythmias, or valvular disease COPD or asthma
- Severe obesity, uncontrolled diabetes, coagulopathy, thyroid disease, or glaucoma
- Neurological risk (e.g., aneurysm, ↑ICP, epilepsy/seizures, severe disorders)
- MAO deficiency or history of serotonin syndrome
- Pregnant, breastfeeding, positive test, or no effective contraception
- Secondary depression
- Cluster B personality disorders (incl. borderline with ≥2 suicidal behaviors in past 12 months) or poor therapeutic rapport
- Psychotic disorders, MDD with psychotic features, or first-degree family history of psychosis/bipolar disorder
- Mania/hypomania (YMRS ≥8)
- OCD, dissociative disorders, active PTSD, or decompensated eating disorders
- Moderate-severe use disorder (past 6 months; except nicotine/caffeine)
- Lifetime ketamine, PCP, psychedelics, or MDMA use disorder
- Current use of MAO inhibitors, unless discontinued at least 14 days prior to dosing
- Psychedelic trial participation in past 12 months
- Cognitive impairment affecting valid assessment
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Interventions
Inhaled N,N-dimethyltryptamine (DMT) administered via a Volcano Medic 2 vaporizer in two inhalations 1 hour apart, using a high-dose regimen (15 mg + 60 mg).
Inhaled N,N-dimethyltryptamine (DMT) administered via a Volcano Medic 2 vaporizer in two inhalations 1 hour apart, using a low-dose regimen (1 mg + 4 mg).
Locations(5)
View Full Details on ClinicalTrials.gov
For the most up-to-date information, visit the official listing.
NCT07562191