TABLE 4

Clinical trials available on ClinicalTrials.gov investigating the use of ayahuasca and DMT for treatment-resistant depression and in healthy individuals

For completed trials, the references of published work were added if available either from the ClinicalTrials.gov web site or PubMed upon searching the NCT identifier. If information was available on the main findings of the study, it was added. If the trial was not completed or it was completed but no information was available in the form of a published original manuscript, we reported the main research question(s) the study aims to address.

CompoundCohortRegimenResearch Question/Main FindingsStatusReference
AyahuascaTreatment-resistant depression2.2 ml/kg, orally, once. Composition: 0.8 mg/ml DMT, 0.21 mg/ml harmine. No harmaline at detection threshold of 0.02 mg/ml (Osório et al., 2015; Sanches et al., 2016) 1 ml/kg, orally, once. Composition: 0.36 mg/ml DMT, 1.86 mg/ml harmine, 0.24 mg/ml harmaline, 1.20 mg/ml tetrahydroharmine (Galvao et al., 2018; de Almeida et al., 2019; Palhano-Fontes et al., 2019; Zeifman et al., 2019; Pasquini et al., 2020)Ayahuasca is a safe and well tolerated approach for TRD. Decreases in up to 80% of patients in depression-related scales from 80 min to day 21. Increased blood perfusion in the left nucleus accumbens, right insula, and left subgenual area. Vomiting in 47% of participants. Ayahuasca elicits fast-acting and sustained antidepressant effects. Ayahuasca decreases suicidality scores and might be useful for suicidality. Increased BDNF levels in patients with TRD and healthy controls 48 h after administration. Ayahuasca acutely increases salivary cortisol but does not affect awakening salivary cortisol response at 48 h in patients with TRD. At 24 h after ayahuasca, increased anterior cingulate cortex connectivity within the salience network, together with decreased PCC connectivity within the DMN, and increased connectivity between the salience and DMN. No effect on the connectivity of primary sensory networksCompletedClinicalTrials.gov Identifier: NCT02914769 (Osório et al., 2015; Sanches et al., 2016; Palhano-Fontes et al., 2019; Galvao et al., 2018; de Almeida et al., 2019; Zeifman et al., 2019; Pasquini et al., 2020)
DMTHealthy volunteers15–25 mg by i.v. bolus + 0.6 to 1 mg/min by i.v. infusion over 90 min (total 69–115 mg)Psychological and physical tolerability of different intravenous DMT administration schedules to investigate the subjective and autonomic effects of prolonged DMT infusion in healthy subjectsNot yet recruitingClinicalTrials.gov Identifier: NCT04353024