Journal of Affective Disorders
February 3, 2023
Guy M Goodwin, Scott T Aaronson, Oscar Alvarez et al.
168 citations
Three weeks after a single dose, 25 mg of psilocybin, and to a lesser extent 10 mg, improved patient-reported measures of depression severity, anxiety, affect, and functioning in people with treatment-resistant depression. These findings extend the primary results from the largest randomized clinical trial of psilocybin for TRD, highlighting outcomes that matter to patients.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
September 1, 2023
Guy M Goodwin, Megan Croal, David Feifel et al.
166 citations
A single 25 mg dose of synthetic psilocybin (COMP360) given alongside psychological support to adults with treatment-resistant depression who continued taking a selective serotonin reuptake inhibitor led to a mean reduction of 14.9 points on the Montgomery-Åsberg Depression Rating Scale at three weeks. Twelve of nineteen participants (63.2%) experienced mild treatment-emergent adverse events that resolved the same day, with no serious events or increased suicidal ideation. Response and remission occurred in 8 participants (42.1%). The authors suggest larger controlled trials are needed to determine whether this approach can benefit patients who cannot safely withdraw from antidepressants.
Journal of affective disorders
March 1, 2025
Guy M Goodwin, Scott T Aaronson, Oscar Alvarez et al.
35 citations
In treatment-resistant depression, a single dose of 25 mg of psilocybin produced stronger correlations between certain psychedelic experiences and depression improvement three weeks later than lower doses. The intensity of psychedelic effects was dose-related, but scores for different doses overlapped considerably. At the 25 mg dose, dimensions of oceanic boundlessness and visual restructuralization, along with emotional breakthrough, showed the strongest correlations with reduced depression scores. The study does not establish causation and requires replication. The overlap in experience intensity across doses suggests unblinding to dose is less likely. Correlations between psychedelic experience and outcome indicate specificity in psilocybin's mechanism of action.
Journal of affective disorders
May 1, 2023
Guy M Goodwin, Megan Croal, Lindsey Marwood et al.
13 citations
Blinding in psychiatric clinical trials is considered ideal, but unblinding due to subjective drug effects raises concerns about demand characteristics undermining research findings. For conventional antidepressants, the strong link between dose and subjective effects does not correspond to a strong relationship with efficacy in randomized controlled trials, disproving the idea that unblinding primarily drives trial outcomes. Instead, early changes in brain function predict treatment outcomes and align with neuroscience. For psychedelic treatment of depression, unblinding is inevitable, but the therapeutic effect stems directly from serotonin receptor activation and altered brain connectivity, not just expectancy. A dose-response relationship is expected with novel mechanisms. Unblinding does not invalidate genuine recovery.
Journal of psychiatric research
December 1, 2024
Lindsey Marwood, Megan Croal, Sunil Mistry et al.
9 citations
In a phase II randomized controlled trial of 233 participants with treatment-resistant depression, those who discontinued antidepressant drugs before receiving psilocybin showed no worsening of depression severity during the discontinuation period, comparable baseline suicidality, and no compromise in psilocybin's treatment efficacy or subjective psychedelic effects relative to those who entered the trial antidepressant-free. The findings suggest that antidepressant discontinuation does not limit the feasibility of psilocybin treatment for treatment-resistant depression and support the homogeneity of psilocybin's effects as a monotherapy.
Journal of affective disorders
August 1, 2026
Guy M Goodwin, Scott T Aaronson, Oscar Alvarez et al.
2 citations
In people with treatment-resistant depression receiving 25 mg psilocybin with monitoring and support, the therapeutic alliance before dosing had only weak correlations with improvement in depression scores at three weeks. Stronger correlations were seen with the intensity of the psychedelic experience itself, particularly emotional breakthrough and visual restructuring. Path analysis suggested that therapeutic alliance helped facilitate the psychedelic experience, but it was the psychedelic experience—not the alliance—that had stronger direct effects on clinical outcomes. The alliance's direct effect on antidepressant response was limited or absent.
Neuroscience Applied
January 1, 2023
Guy M. Goodwin, Megan Croal, J. Chai-Rees et al.
No Summary