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Mushrooms / Psilocybin

Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder: A Randomized Clinical Trial

Abstract

Importance: Major depressive disorder (MDD) is a substantial public health burden, but current treatments have limited effectiveness and adherence. Recent evidence suggests that 1 or 2 administrations of psilocybin with psychological support produces antidepressant effects in patients with cancer and in those with treatment-resistant depression.

Objective: To investigate the effect of psilocybin therapy in patients with MDD.

Design, setting, and participants: This randomized, waiting list-controlled clinical trial was conducted at the Center for Psychedelic and Consciousness Research at Johns Hopkins Bayview Medical Center in Baltimore, Maryland. Adults aged 21 to 75 years with an MDD diagnosis, not currently using antidepressant medications, and without histories of psychotic disorder, serious suicide attempt, or hospitalization were eligible to participate. Enrollment occurred between August 2017 and April 2019, and the 4-week primary outcome assessments were completed in July 2019. A total of 27 participants were randomized to an immediate treatment condition group (n = 15) or delayed treatment condition group (waiting list control condition; n = 12). Data analysis was conducted from July 1, 2019, to July 31, 2020, and included participants who completed the intervention (evaluable population).

Interventions: Two psilocybin sessions (session 1: 20 mg/70 kg; session 2: 30 mg/70 kg) were given (administered in opaque gelatin capsules with approximately 100 mL of water) in the context of supportive psychotherapy (approximately 11 hours). Participants were randomized to begin treatment immediately or after an 8-week delay.

Main outcomes and measures: The primary outcome, depression severity was assessed with the GRID-Hamilton Depression Rating Scale (GRID-HAMD) scores at baseline (score of ≥17 required for enrollment) and weeks 5 and 8 after enrollment for the delayed treatment group, which corresponded to weeks 1 and 4 after the intervention for the immediate treatment group. Secondary outcomes included the Quick Inventory of Depressive Symptomatology-Self Rated (QIDS-SR).

Results: Of the randomized participants, 24 of 27 (89%) completed the intervention and the week 1 and week 4 postsession assessments. This population had a mean (SD) age of 39.8 (12.2) years, was composed of 16 women (67%), and had a mean (SD) baseline GRID-HAMD score of 22.8 (3.9). The mean (SD) GRID-HAMD scores at weeks 1 and 4 (8.0 [7.1] and 8.5 [5.7]) in the immediate treatment group were statistically significantly lower than the scores at the comparable time points of weeks 5 and 8 (23.8 [5.4] and 23.5 [6.0]) in the delayed treatment group. The effect sizes were large at week 5 (Cohen d = 2.5; 95% CI, 1.4-3.5; P < .001) and week 8 (Cohen d = 2.6; 95% CI, 1.5-3.7; P < .001). The QIDS-SR documented a rapid decrease in mean (SD) depression score from baseline to day 1 after session 1 (16.7 [3.5] vs 6.3 [4.4]; Cohen d = 2.6; 95% CI, 1.8-3.5; P < .001), which remained statistically significantly reduced through the week 4 follow-up (6.0 [5.7]; Cohen d = 2.3; 95% CI, 1.5-3.0; P < .001). In the overall sample, 17 participants (71%) at week 1 and 17 (71%) at week 4 had a clinically significant response to the intervention (≥50% reduction in GRID-HAMD score), and 14 participants (58%) at week 1 and 13 participants (54%) at week 4 were in remission (≤7 GRID-HAMD score).

Conclusions and relevance: Findings suggest that psilocybin with therapy is efficacious in treating MDD, thus extending the results of previous studies of this intervention in patients with cancer and depression and of a nonrandomized study in patients with treatment-resistant depression.

Trial registration: ClinicalTrials.gov Identifier: NCT03181529.

Davis, A. K., Barrett, F. S., May, D. G., Cosimano, M. P., Sepeda, N. D., Johnson, M. W., Finan, P. H., & Griffiths, R. R. (2021). Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder: A Randomized Clinical Trial. JAMA psychiatry, 78(5), 481–489. https://doi.org/10.1001/jamapsychiatry.2020.3285

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Harnessing psilocybin: antidepressant-like behavioral and synaptic actions of psilocybin are independent of 5-HT2R activation in mice

Abstract

Depression is a widespread and devastating mental illness and the search for rapid-acting antidepressants remains critical. There is now exciting evidence that the psychedelic compound psilocybin produces not only powerful alterations of consciousness, but also rapid and persistent antidepressant effects. How psilocybin exerts its therapeutic actions is not known, but it is widely presumed that these actions require altered consciousness, which is known to be dependent on serotonin 2A receptor (5-HT2AR) activation. This hypothesis has never been tested, however. We therefore asked whether psilocybin would exert antidepressant-like responses in mice and, if so, whether these responses required 5-HT2AR activation. Using chronically stressed male mice, we observed that a single injection of psilocybin reversed anhedonic responses assessed with the sucrose preference and female urine preference tests. The antianhedonic response to psilocybin was accompanied by a strengthening of excitatory synapses in the hippocampus-a characteristic of traditional and fast-acting antidepressants. Neither behavioral nor electrophysiological responses to psilocybin were prevented by pretreatment with the 5-HT2A/2C antagonist ketanserin, despite positive evidence of ketanserin’s efficacy. We conclude that psilocybin’s mechanism of antidepressant action can be studied in animal models and suggest that altered perception may not be required for its antidepressant effects. We further suggest that a 5-HT2AR-independent restoration of synaptic strength in cortico-mesolimbic reward circuits may contribute to its antidepressant action. The possibility of combining psychedelic compounds and a 5-HT2AR antagonist offers a potential means to increase their acceptance and clinical utility and should be studied in human depression.

Hesselgrave, N., Troppoli, T. A., Wulff, A. B., Cole, A. B., & Thompson, S. M. (2021). Harnessing psilocybin: antidepressant-like behavioral and synaptic actions of psilocybin are independent of 5-HT2R activation in mice. Proceedings of the National Academy of Sciences of the United States of America, 118(17), e2022489118. https://doi.org/10.1073/pnas.2022489118

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Trial of Psilocybin versus Escitalopram for Depression

Abstract

Background: Psilocybin may have antidepressant properties, but direct comparisons between psilocybin and established treatments for depression are lacking.

Methods: In a phase 2, double-blind, randomized, controlled trial involving patients with long-standing, moderate-to-severe major depressive disorder, we compared psilocybin with escitalopram, a selective serotonin-reuptake inhibitor, over a 6-week period. Patients were assigned in a 1:1 ratio to receive two separate doses of 25 mg of psilocybin 3 weeks apart plus 6 weeks of daily placebo (psilocybin group) or two separate doses of 1 mg of psilocybin 3 weeks apart plus 6 weeks of daily oral escitalopram (escitalopram group); all the patients received psychological support. The primary outcome was the change from baseline in the score on the 16-item Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR-16; scores range from 0 to 27, with higher scores indicating greater depression) at week 6. There were 16 secondary outcomes, including QIDS-SR-16 response (defined as a reduction in score of >50%) and QIDS-SR-16 remission (defined as a score of ≤5) at week 6.

Results: A total of 59 patients were enrolled; 30 were assigned to the psilocybin group and 29 to the escitalopram group. The mean scores on the QIDS-SR-16 at baseline were 14.5 in the psilocybin group and 16.4 in the escitalopram group. The mean (±SE) changes in the scores from baseline to week 6 were -8.0±1.0 points in the psilocybin group and -6.0±1.0 in the escitalopram group, for a between-group difference of 2.0 points (95% confidence interval [CI], -5.0 to 0.9) (P = 0.17). A QIDS-SR-16 response occurred in 70% of the patients in the psilocybin group and in 48% of those in the escitalopram group, for a between-group difference of 22 percentage points (95% CI, -3 to 48); QIDS-SR-16 remission occurred in 57% and 28%, respectively, for a between-group difference of 28 percentage points (95% CI, 2 to 54). Other secondary outcomes generally favored psilocybin over escitalopram, but the analyses were not corrected for multiple comparisons. The incidence of adverse events was similar in the trial groups.

Conclusions: On the basis of the change in depression scores on the QIDS-SR-16 at week 6, this trial did not show a significant difference in antidepressant effects between psilocybin and escitalopram in a selected group of patients. Secondary outcomes generally favored psilocybin over escitalopram, but the analyses of these outcomes lacked correction for multiple comparisons. Larger and longer trials are required to compare psilocybin with established antidepressants.

Carhart-Harris, R., Giribaldi, B., Watts, R., Baker-Jones, M., Murphy-Beiner, A., Murphy, R., Martell, J., Blemings, A., Erritzoe, D., & Nutt, D. J. (2021). Trial of Psilocybin versus Escitalopram for Depression. The New England journal of medicine, 384(15), 1402–1411. https://doi.org/10.1056/NEJMoa2032994

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Spontaneous and deliberate creative cognition during and after psilocybin exposure

Abstract

Creativity is an essential cognitive ability linked to all areas of our everyday functioning. Thus, finding a way to enhance it is of broad interest. A large number of anecdotal reports suggest that the consumption of psychedelic drugs can enhance creative thinking; however, scientific evidence is lacking. Following a double-blind, placebo-controlled, parallel-group design, we demonstrated that psilocybin (0.17 mg/kg) induced a time- and construct-related differentiation of effects on creative thinking. Acutely, psilocybin increased ratings of (spontaneous) creative insights, while decreasing (deliberate) task-based creativity. Seven days after psilocybin, number of novel ideas increased. Furthermore, we utilized an ultrahigh field multimodal brain imaging approach, and found that acute and persisting effects were predicted by within- and between-network connectivity of the default mode network. Findings add some support to historical claims that psychedelics can influence aspects of the creative process, potentially indicating them as a tool to investigate creativity and subsequent underlying neural mechanisms. Trial NL6007; psilocybin as a tool for enhanced cognitive flexibility; https://www.trialregister.nl/trial/6007 .

Mason, N. L., Kuypers, K., Reckweg, J. T., Müller, F., Tse, D., Da Rios, B., Toennes, S. W., Stiers, P., Feilding, A., & Ramaekers, J. G. (2021). Spontaneous and deliberate creative cognition during and after psilocybin exposure. Translational psychiatry, 11(1), 209. https://doi.org/10.1038/s41398-021-01335-5

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Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action

Abstract

Major depressive disorder (MDD) is among the most prevalent mental health disorders worldwide, and it is associated with a reduced quality of life and enormous costs to health care systems. Available drug treatments show low-to-moderate response in most patients, with almost a third of patients being non-responders (treatment-resistant). Furthermore, most currently available medications need several weeks to achieve therapeutic effects, and the long-term use of these drugs is often associated with significant unwanted side effects and resultant reductions in treatment compliance. Therefore, more effective, safer, and faster-acting antidepressants with enduring effects are needed. Together with ketamine, psychedelics (or classic or serotoninergic hallucinogens) such as lysergic acid diethylamide (LSD), psilocybin, and ayahuasca are among the few compounds with recent human evidence of fast-acting antidepressant effects. Several studies in the 1950s to 1970s reported antidepressive and anxiolytic effects of these drugs, which are being confirmed by modern trials (LSD, one trial; psilocybin, five trials; ayahuasca, two trials). The effects of these drugs appear to be produced primarily by their agonism at serotonin (5-hydroxytryptamine, 5-HT) receptors, especially the 5-HT2A receptor. Considering the overall burden of MDD and the necessity of new therapeutic options, the promising (but currently limited) evidence of safety and efficacy of psychedelics has encouraged the scientific community to explore more fully their beneficial effects in MDD.

Dos Santos, R. G., Hallak, J. E., Baker, G., & Dursun, S. (2021). Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action. Journal of psychopharmacology (Oxford, England), 35(4), 453–458. https://doi.org/10.1177/0269881120986422

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Acute and Sustained Reductions in Loss of Meaning and Suicidal Ideation Following Psilocybin-Assisted Psychotherapy for Psychiatric and Existential Distress in Life-Threatening Cancer

Abstract

People with advanced cancer are at heightened risk of desire for hastened death (DHD), suicidal ideation (SI), and completed suicide. Loss of Meaning (LoM), a component of demoralization, can be elevated by a cancer diagnosis and predicts DHD and SI in this population. We completed a randomized controlled trial in which psilocybin-assisted psychotherapy (PAP) produced rapid and sustained improvements in depression, demoralization, and hopelessness in people with cancer. Converging epidemiologic and clinical trial findings suggests a potential antisuicidal effect of this treatment. To probe our hypothesis that PAP relieves SI through its beneficial impacts on depression and demoralization (LoM in particular), we performed secondary analyses assessing within- and between-group differences with regard to LoM and an SI composite score. Among participants with elevated SI at baseline, PAP was associated with within-group reductions in SI that were apparent as early as 8 h and persisted for 6.5 months postdosing. PAP also produced large reductions in LoM from baseline that were apparent 2 weeks after treatment and remained significant and robust at the 6.5 month and 3.2 and 4.5 year follow-ups. Exploratory analyses support our hypothesis and suggest that PAP may be an effective antisuicidal intervention following a cancer diagnosis due to its positive impact on hopelessness and demoralization and its effects on meaning-making in particular. These preliminary results implicate psilocybin treatment as a potentially effective alternative to existing antidepressant medications in patients with cancer that are also suicidal, and warrant further investigation in participants with elevated levels of depression and suicidality.

Ross, S., Agin-Liebes, G., Lo, S., Zeifman, R. J., Ghazal, L., Benville, J., Franco Corso, S., Bjerre Real, C., Guss, J., Bossis, A., & Mennenga, S. E. (2021). Acute and Sustained Reductions in Loss of Meaning and Suicidal Ideation Following Psilocybin-Assisted Psychotherapy for Psychiatric and Existential Distress in Life-Threatening Cancer. ACS pharmacology & translational science, 4(2), 553–562. https://doi.org/10.1021/acsptsci.1c00020

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Chemoenzymatic Synthesis of 5-Methylpsilocybin: A Tryptamine with Potential Psychedelic Activity

Abstract

A novel analogue of psilocybin was produced by hybrid chemoenzymatic synthesis in sufficient quantity to enable bioassay. Utilizing purified 4-hydroxytryptamine kinase from Psilocybe cubensis, chemically synthesized 5-methylpsilocin (2) was enzymatically phosphorylated to provide 5-methylpsilocybin (1). The zwitterionic product was isolated from the enzymatic step with high purity utilizing a solvent-antisolvent precipitation approach. Subsequently, 1 was tested for psychedelic-like activity using the mouse head-twitch response assay, which indicated activity that was more potent than the psychedelic dimethyltryptamine, but less potent than that of psilocybin.

Fricke, J., Sherwood, A. M., Halberstadt, A. L., Kargbo, R. B., & Hoffmeister, D. (2021). Chemoenzymatic Synthesis of 5-Methylpsilocybin: A Tryptamine with Potential Psychedelic Activity. Journal of natural products, 84(4), 1403–1408. https://doi.org/10.1021/acs.jnatprod.1c00087

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Dose-response relationships of psilocybin-induced subjective experiences in humans

Abstract

Background: Psilocybin is the psychoactive component in Psilocybe mushrooms (‘magic mushrooms’). Whether and how the quality of the psilocybin-induced experience might mediate beneficial health outcomes is currently under investigation, for example, in therapeutic applications. However, to date, no meta-analysis has investigated the dose-dependency of subjective experiences across available studies.

Aim: Establishing dose-response relationships of the subjective experiences induced by psilocybin in healthy study participants and a comparison of patient groups.

Method: We applied a linear meta-regression approach, based on the robust variance estimation framework, to obtain linear dose-response relationship estimates on questionnaire ratings after oral psilocybin administration. Data were obtained from the Altered States Database, which contains data extracted from MEDLINE-listed journal articles that used standardized and validated questionnaires: the Altered States of Consciousness Rating Scale, the Mystical Experience Questionnaire and the Hallucinogen Rating Scale.

Results: Psilocybin dose positively correlated with ratings on most factors and scales, mainly those referring to perceptual alterations and positively experienced ego dissolution. Measures referring to challenging experiences exhibited small effects and were barely modulated by dose.

Conclusion: Psilocybin intensified almost all characteristics of altered states of consciousness assessed with the given questionnaires. Because subjective experiences are not only determined by dose, but also by individual and environmental factors, the results may only apply to controlled laboratory experiments and not to recreational use. This paper may serve as a general literature citation for the use of psilocybin in experimental and clinical research, to compare expected and observed subjective experiences.

Hirschfeld, T., & Schmidt, T. T. (2021). Dose-response relationships of psilocybin-induced subjective experiences in humans. Journal of psychopharmacology (Oxford, England), 35(4), 384–397. https://doi.org/10.1177/0269881121992676

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Low Doses of Psilocybin and Ketamine Enhance Motivation and Attention in Poor Performing Rats: Evidence for an Antidepressant Property

Abstract

Long term benefits following short-term administration of high psychedelic doses of serotonergic and dissociative hallucinogens, typified by psilocybin and ketamine respectively, support their potential as treatments for psychiatric conditions such as major depressive disorder. The high psychedelic doses induce perceptual experiences which are associated with therapeutic benefit. There have also been anecdotal reports of these drugs being used at what are colloquially referred to as “micro” doses to improve mood and cognitive function, although currently there are recognized limitations to their clinical and preclinical investigation. In the present studies we have defined a low dose and plasma exposure range in rats for both ketamine (0.3-3 mg/kg [10-73 ng/ml]) and psilocybin/psilocin (0.05-0.1 mg/kg [7-12 ng/ml]), based on studies which identified these as sub-threshold for the induction of behavioral stereotypies. Tests of efficacy were focused on depression-related endophenotypes of anhedonia, amotivation and cognitive dysfunction using low performing male Long Evans rats trained in two food motivated tasks: a progressive ratio (PR) and serial 5-choice (5-CSRT) task. Both acute doses of ketamine (1-3 mg/kg IP) and psilocybin (0.05-0.1 mg/kg SC) pretreatment increased break point for food (PR task), and improved attentional accuracy and a measure of impulsive action (5-CSRT task). In each case, effect size was modest and largely restricted to test subjects characterized as “low performing”. Furthermore, both drugs showed a similar pattern of effect across both tests. The present studies provide a framework for the future study of ketamine and psilocybin at low doses and plasma exposures, and help to establish the use of these lower concentrations of serotonergic and dissociative hallucinogens both as a valid scientific construct, and as having a therapeutic utility.

Higgins, G. A., Carroll, N. K., Brown, M., MacMillan, C., Silenieks, L. B., Thevarkunnel, S., Izhakova, J., Magomedova, L., DeLannoy, I., & Sellers, E. M. (2021). Low Doses of Psilocybin and Ketamine Enhance Motivation and Attention in Poor Performing Rats: Evidence for an Antidepressant Property. Frontiers in pharmacology, 12, 640241. https://doi.org/10.3389/fphar.2021.640241

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The Evolved Psychology of Psychedelic Set and Setting: Inferences Regarding the Roles of Shamanism and Entheogenic Ecopsychology

Abstract

This review illustrates the relevance of shamanism and its evolution under effects of psilocybin as a framework for identifying evolved aspects of psychedelic set and setting. Effects of 5HT2 psychedelics on serotonin, stress adaptation, visual systems and personality illustrate adaptive mechanisms through which psychedelics could have enhanced hominin evolution as an environmental factor influencing selection for features of our evolved psychology. Evolutionary psychology perspectives on ritual, shamanism and psychedelics provides bases for inferences regarding psychedelics’ likely roles in hominin evolution as exogenous neurotransmitter sources through their effects in selection for innate dispositions for psychedelic set and setting. Psychedelics stimulate ancient brain structures and innate modular thought modules, especially self-awareness, other awareness, “mind reading,” spatial and visual intelligences. The integration of these innate modules are also core features of shamanism. Cross-cultural research illustrates shamanism is an empirical phenomenon of foraging societies, with its ancient basis in collective hominid displays, ritual alterations of consciousness, and endogenous healing responses. Shamanic practices employed psychedelics and manipulated extrapharmacological effects through stimulation of serotonin and dopamine systems and augmenting processes of the reptilian and paleomammalian brains. Differences between chimpanzee maximal displays and shamanic rituals reveal a zone of proximal development in hominin evolution. The evolution of the mimetic capacity for enactment, dance, music, and imitation provided central capacities underlying shamanic performances. Other chimp-human differences in ritualized behaviors are directly related to psychedelic effects and their integration of innate modular thought processes. Psychedelics and other ritual alterations of consciousness stimulate these and other innate responses such as soul flight and death-and-rebirth experiences. These findings provided bases for making inferences regarding foundations of our evolved set, setting and psychology. Shamanic setting is eminently communal with singing, drumming, dancing and dramatic displays. Innate modular thought structures are prominent features of the set of shamanism, exemplified in animism, animal identities, perceptions of spirits, and psychological incorporation of spirit others. A shamanic-informed psychedelic therapy includes: a preparatory set with practices such as sexual abstinence, fasting and dream incubation; a set derived from innate modular cognitive capacities and their integration expressed in a relational animistic worldview; a focus on internal imagery manifesting a presentational intelligence; and spirit relations involving incorporation of animals as personal powers. Psychedelic research and treatment can adopt this shamanic biogenetic paradigm to optimize set, setting and ritual frameworks to enhance psychedelic effects.

Winkelman M. J. (2021). The Evolved Psychology of Psychedelic Set and Setting: Inferences Regarding the Roles of Shamanism and Entheogenic Ecopsychology. Frontiers in pharmacology, 12, 619890. https://doi.org/10.3389/fphar.2021.619890

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30 April - Q&A with Rick Strassman

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