Psilocybin for Cancer Anxiety: The NYU and Hopkins Trials

Psilocybin & End-of-Life

78% depression response at 6 months

The Johns Hopkins psilocybin cancer trial found 78% of patients met criteria for clinically significant depression response and 83% for anxiety at its 6-month follow-up, from a single high-dose session.

Griffiths et al., Journal of Psychopharmacology, 2016

60–80%

of surviving NYU trial participants still met clinical response criteria an average of 4.5 years after a single session (Agin-Liebes 2020, n=15)

83% vs 14%

antidepressant response on the BDI at 7 weeks, psilocybin-first vs niacin-first, in the NYU trial (Ross 2016)

8 hours

how quickly suicidal ideation fell in a within-group secondary analysis of NYU participants who had elevated ideation at baseline (Ross 2021)

Griffiths et al., Journal of Psychopharmacology, 2016

View as image ↗

In December 2016, two separate research teams published two separate randomized controlled trials in the same issue of the same journal. The coordination was deliberate. Both teams — one at Johns Hopkins, one at NYU — had been running independent psilocybin cancer anxiety trials, and they agreed to submit simultaneously so neither would be scooped and the combined evidentiary weight would land in one place at one moment. The result was a milestone in psilocybin cancer anxiety research: back-to-back evidence that a single guided session with psilocybin produced rapid and substantial reductions in anxiety and depression in people with life-threatening cancer, with benefits still measurable months later.

This article covers what those trials actually found, what makes their design trustworthy, what the long-term follow-up data reveal — and, just as importantly, where the published numbers are weaker or more heavily caveated than popular summaries suggest.

For the full overview of psilocybin evidence in cancer patients, see Psilocybin for Cancer Patients: Reducing Existential Anxiety.

The Forgotten Pilot: Why 12 Patients in 2011 Made the 2016 Trials Possible

Before Hopkins or NYU could enroll cancer patients in a full randomized trial, someone had to establish that giving a psychedelic compound to people who were already physically ill and psychologically distressed was safe enough to try. That someone was Charles Grob and colleagues, who published the first modern controlled psilocybin cancer trial in 2011.^[3]

Grob's pilot enrolled 12 adults with advanced-stage cancer and reactive anxiety. Each participant received a moderate dose of psilocybin (0.2 mg/kg) in one session and niacin (250 mg) — a vitamin that causes flushing and warmth but no psychoactive effects — in a separate session, with participants acting as their own controls in a double-blind design. The primary question was not efficacy but safety: would psilocybin produce cardiac events, acute psychological crises, or lasting harm in this population?

It did not. Physiological and psychological responses were documented as safe, and no clinically significant adverse events occurred with psilocybin. As secondary findings, trait anxiety on the State-Trait Anxiety Inventory decreased significantly at 1-month and 3-month follow-up, and Beck Depression Inventory scores showed a mood improvement that reached significance at 6 months. A third measure, the Profile of Mood States, showed improvement that approached but did not reach statistical significance.

Meanwhile, at Hopkins, Roland Griffiths and his team had been doing foundational work on psilocybin's subjective effects since 2006. In a double-blind study of 30 hallucinogen-naïve adults who regularly participated in religious or spiritual activities, Griffiths compared psilocybin (30 mg/70 kg) against methylphenidate (40 mg/70 kg) as a comparison compound.^[9] Psilocybin increased measures of mystical experience, and at 2-month follow-up volunteers rated the session as having substantial personal meaning and spiritual significance, attributing to it sustained positive changes in attitudes and behavior — changes that community observers independently corroborated. If that class of experience could be produced reliably, and cancer patients could safely have one, the therapeutic question became worth asking.

December 2016: Two Teams, Same Journal, One Carefully Coordinated Month

The Journal of Psychopharmacology's December 2016 issue contained something unusual: two randomized controlled trials on the same intervention for the same population, accompanied by a large set of expert commentaries.

The coordination between the Hopkins and NYU teams was intentional. Both groups had been running their trials independently, with different designs, different comparator conditions, and different primary measures. They agreed to submit simultaneously to avoid a situation where one trial published first and shaped how the other would be interpreted. Together, the two trials carried more weight than either alone — if results converged despite different research teams, different doses, different placebos, and different outcome instruments, the findings would be harder to attribute to any single team's methods or biases.

They did converge.

Both trials found rapid and significant reductions in cancer-related anxiety and depression that outlasted the pharmacological window of the drug by months. Both found that the intensity of the mystical or transcendent quality of the session mediated clinical outcomes. The coordinated publication was a calculated bet that consistency across independent trials would change the field's assessment of what psilocybin could do — and it substantially did.

The Hopkins Trial: What 51 Patients Showed

The Hopkins trial, led by Griffiths and colleagues, enrolled 51 cancer patients with life-threatening diagnoses and symptoms of depression and/or anxiety.^[2] Each participant received two sessions in counterbalanced order, 5 weeks apart: one with high-dose psilocybin (22 or 30 mg per 70 kg of body weight) and one with a very low, placebo-like dose (1 or 3 mg per 70 kg). The very-low-dose session served as the control condition — pharmacologically active enough to blunt participants' certainty about which session was which, but too weak to be expected to produce meaningful therapeutic effects.

Landmark Trial

Griffiths et al. (2016) · Journal of Psychopharmacology

Population

51 adults with life-threatening cancer diagnoses and clinically significant depression and/or anxiety

Intervention

Single high-dose psilocybin session, 22 or 30 mg/70 kg, with psychological support

Comparator

Very low ('placebo-like') dose psilocybin, 1 or 3 mg/70 kg, in counterbalanced crossover 5 weeks apart

Finding

At the 6-month follow-up, 78% met criteria for clinically significant depression response (GRID-HAMD-17) and 83% for anxiety response (HAM-A). Remission rates were 65% and 57% respectively. Mystical-type experience on session day mediated the dose–outcome relationship.

positive Large, well-controlled for its field — but crossover design means the later follow-up data have no untreated comparison group.

Griffiths RR, et al. J Psychopharmacol. 2016;30(12):1181-1197. PMID 27909165

At the 6-month follow-up — approximately 211 days after the second session — outcomes were assessed with the GRID-HAMD-17 (a clinician-rated depression scale) and the HAM-A (a clinician-rated anxiety scale). Seventy-eight percent of participants met criteria for a clinically significant depression response; 83% met criteria for an anxiety response. Sixty-five percent were in remission on the depression measure and 57% on the anxiety measure — meaning their scores had dropped into the normal range, not merely improved.

Secondary outcomes including quality of life, life meaning, optimism, and death anxiety all improved significantly. The intensity of the mystical experience during the session, measured with the Mystical Experience Questionnaire, mediated the effect of psilocybin dose on therapeutic outcome: participants who had deeper, more transcendent sessions had better depression and anxiety outcomes months later.

The Hopkins design had one notable limitation: using a very low dose of the same drug as the control means participants could plausibly detect the difference between sessions and infer which was active. The NYU team addressed this differently.

The NYU Trial: 29 Patients, Niacin, and Demoralization on the Scorecard

The NYU trial, led by Stephen Ross and colleagues, enrolled 29 cancer patients in a similar crossover design but used niacin — the vitamin that causes temporary flushing and warmth — as the comparator instead of low-dose psilocybin.^[1] The intent was better blinding: niacin's noticeable physical side effects make participants less certain whether they received the psychoactive drug.

The NYU trial used a single dose of 0.3 mg per kg of body weight, delivered alongside psychotherapy. The primary outcomes were anxiety and depression assessed between groups prior to the crossover at 7 weeks. At that point, 83% of participants in the psilocybin-first group met criteria for antidepressant response on the Beck Depression Inventory, compared with 14% of the niacin-first group. On the HADS anxiety subscale, 58% of the psilocybin-first group met anxiolytic response criteria versus 14% on niacin. At the 6.5-month follow-up, approximately 60-80% of participants continued to show clinically significant reductions in depression or anxiety. Seventy percent rated the psilocybin session as the single or among the top five most personally meaningful experiences of their lives.

What made the NYU trial distinctive was its outcome measurement. Ross's team specifically included the Demoralization Scale — a measure of the collapse of meaning and inability to cope that goes beyond standard depression assessment — as a formal endpoint, alongside a hopelessness measure and spiritual well-being. At the time, this was unusual. Demoralization and hopelessness both decreased, spiritual well-being improved, and attitudes toward death improved. The NYU trial was the first cancer psilocybin RCT to formally document that psilocybin's effect extends to the existential dimension of suffering, not just to symptom scores on depression and anxiety scales.

For a detailed account of what psilocybin does specifically for demoralization syndrome, see Psilocybin and Demoralization: Hope for the Hopeless.

Hopkins vs. NYU: The Trials Side by Side

The 8-Hour Finding: What Happened to Suicidal Ideation After a Single Dose

The primary outcomes of both 2016 trials focused on anxiety and depression. A secondary analysis of the NYU cohort, published in 2021, examined two variables the original papers had not specifically reported: loss of meaning and suicidal ideation.^[5]

Both are core features of the existential distress that advanced-cancer patients face, and both are among the hardest things to shift with standard pharmacology. Among participants who had detectable elevated suicidal ideation at baseline, psilocybin-assisted psychotherapy was associated with within-group reductions in suicidal ideation that were apparent as early as 8 hours after dosing and persisted through 6.5 months. Large reductions in loss of meaning appeared 2 weeks after treatment and remained significant at the 6.5-month, 3.2-year, and 4.5-year assessments.

Standard antidepressants typically take weeks to produce measurable changes in suicidal ideation, because their mechanisms depend on chronic exposure. A within-session shift is mechanistically different in kind. But the strength of this particular finding needs to be stated honestly.

Fact Check

'Psilocybin cuts suicidal thinking in 8 hours'

The claim

“A single psilocybin dose reduces suicidal ideation within 8 hours — faster than any antidepressant.”

Popular coverage of the Ross et al. 2021 secondary analysis of the NYU cohort.

What research shows

Overstated

The 8-hour signal is real but narrow: it is a within-group change, in the subset of participants who had elevated suicidal ideation at baseline, from a secondary analysis of a trial that was not designed to test antisuicidal effects.

The authors describe the results as preliminary and note the study was substantially underpowered to detect small-to-moderate effects. There is no between-group antisuicidal comparison, and no confirmatory trial. The finding is a hypothesis worth testing, not an established clinical effect.

Ross S, et al. ACS Pharmacol Transl Sci. 2021;4(2):553-562. PMID 33860185

For more on how a single psilocybin dose changes the relationship with death fear, see How a Single Dose of Psilocybin Reduces Death Anxiety.

Four and a Half Years Later: The Durability Evidence

The standard follow-up window in clinical trials is 3-6 months. Agin-Liebes and colleagues took the unusual step of tracking down the surviving participants from the NYU cohort years after treatment.^[4]

All 16 participants who were still alive were contacted, and 15 agreed to participate, assessed at an average of 3.2 years and again at 4.5 years after psilocybin administration. Reductions in anxiety, depression, hopelessness, demoralization, and death anxiety were sustained at both follow-ups, with large within-group effect sizes. At the 4.5-year assessment, approximately 60-80% of participants met criteria for clinically significant antidepressant or anxiolytic responses. Between 71% and 100% of participants — depending on the specific item — attributed positive life changes to the psilocybin experience and rated it among the most personally meaningful and spiritually significant experiences of their lives.

These participants had not received additional psilocybin doses as part of the study. A single guided session was followed by changes that remained measurable four and a half years later.

For the meaning-making dimension of what persists at 4.5 years, see Psilocybin and Meaning-Making at End of Life.

What the Meta-Analyses Add — and Where They Disagree

A single trial's results can be attributed to researcher bias, unusual sample characteristics, or chance. Meta-analyses pool results across trials and test whether effects hold. For psilocybin in cancer populations, the pooled picture is genuinely encouraging for depression and noticeably messier for anxiety.

Yu and colleagues' 2021 meta-analysis examined psilocybin for end-of-life anxiety specifically, pooling five studies.^[6] Psilocybin outperformed placebo on state anxiety at 1 day (Hedges' g = -0.70) and 2 weeks (-1.03), and on trait anxiety at 1 day (-0.71), 2 weeks (-1.08), and 6 months (-0.84). It also produced a transient elevation in systolic (+19.00 mmHg) and diastolic (+8.66 mmHg) blood pressure relative to placebo, while differences in all-cause discontinuation, serious adverse events, and heart rate were non-significant.

The Moshfeghinia 2026 meta-analysis pooled seven studies, three of them double-blind controlled crossover trials.^[7] Across RCTs, psilocybin significantly reduced depressive symptoms on the Beck Depression Inventory (SMD = -2.87, 95% CI: -3.99 to -1.76, p<0.001) and on the HADS depression subscale (SMD = -2.97, 95% CI: -3.60 to -2.33, p<0.001). Benefits on both persisted in the 6-month analyses.

Anxiety was a different story. In the same meta-analysis, the HADS anxiety subscale did not reach significance (SMD = -3.63, p=0.11), and State-Trait Anxiety Inventory results were inconsistent. The authors' own conclusion is measured: given the small number of studies, high heterogeneity, blinding and expectancy problems, and the fact that psilocybin was almost always co-administered with psychotherapy, they describe the findings as preliminary and call for larger, rigorously blinded trials.

Swieczkowski and colleagues' 2025 network meta-analysis included just two RCTs and compared psilocybin doses against their control conditions on day 1 and at 2 weeks.^[8] Psilocybin reduced BDI scores at day 1 (MD = 2.26; p=0.01), though that effect was not sustained at 2 weeks. STAI state anxiety showed substantial reductions at both day 1 (MD = 11.52) and 2 weeks (MD = 12.66). The highest dose studied, 0.3 mg/kg, ranked best, with SUCRA values of 87.81% for BDI depression, 91.58% for state anxiety, and 94.2% for trait anxiety. SUCRA summarizes where a treatment sits across the whole ranking distribution — a value near 100% means the treatment consistently ranks at or near the top, not that it won a specific percentage of simulations. With two trials in the network, the authors themselves urge cautious interpretation.

A 2025 systematic review by Lapid and colleagues covered 14 studies — three RCTs, five open-label trials, five qualitative studies, and one case report.^[11] Psilocybin therapy consistently showed significant reductions in depression, anxiety, and existential distress, with improvements sustained over several months and adverse effects that were generally mild and transient.

Evidence Position

1. Mechanistic workcompleted

   5-HT2A agonism and acute network-level brain changes are well characterized

2. Animal modelscompleted

   Limited relevance — existential distress has no good animal analogue

3. Case reports & qualitative studiescompleted

   Six of the 14 studies in Lapid 2025 were qualitative or single-case

4. Small randomized trialscurrent

   Grob 2011 (n=12), Ross 2016 (n=29), Griffiths 2016 (n=51), M. Ross 2025 (n=35)

5. Large multi-site RCTsmissing

   No adequately powered, multi-site, rigorously blinded trial has reported

6. Meta-analysescompleted

   Several exist, but they pool the same handful of small trials — they cannot fix the underlying sample-size problem

The evidence base is consistent in direction and unusually durable in follow-up, but it rests on roughly 130 randomized participants across four small trials. Meta-analyses recycle those same participants rather than adding new ones. The missing rung is a large, multi-site, properly blinded trial.

Grob 2011 (PMID 20819978); Ross 2016 (PMID 27909164); Griffiths 2016 (PMID 27909165); Ross ML 2025 (PMID 40858059); Lapid 2025 (PMID 40259688)

The most recent formal trial is a 2025 phase 2b randomized controlled trial led by Margaret Ross at St. Vincent's Hospital Melbourne — an independent Australian team, not a continuation of the NYU work despite the shared surname.^[10] Thirty-five participants with life-threatening illness were randomized to 25 mg psilocybin (n=17) or 100 mg niacin as active placebo (n=18), each alongside three preparatory and six integration psychotherapy sessions. At 6-7 weeks, psilocybin produced significantly greater reductions in HADS depression (B = -2.49; p=.02; d=1.12), BDI-II (B = -7.56; p=.004; d=2.97), and STAI state anxiety (B = -12.59; p=.005; d=4.51). Benefits were sustained at 26 weeks, and exploratory outcomes showed reductions in demoralization, death anxiety, and hopelessness. No serious treatment-emergent adverse events occurred; one participant withdrew due to anxiety during dosing.

That an independent team on another continent, nearly a decade later, reproduced the same pattern of results is the strongest argument that the 2016 findings were not a fluke of two American research groups.

Safety & Context

Critical

These results come from supervised clinical trials, not self-administration

Concern

Every trial described here administered psilocybin in a medical setting, at a measured dose, with screening for cardiac and psychiatric risk, and with trained therapists present for preparation, the 6-8 hour session itself, and structured integration afterward. Psilocybin also produced transient blood pressure elevations averaging +19 mmHg systolic, and acute anxiety during dosing was common enough that one participant in the 2025 phase 2b trial withdrew because of it.

What the research says

The therapeutic result is a product of the whole protocol — screening, dose, setting, and psychotherapy — not of the molecule alone. No trial evidence supports unsupervised use, and the meta-analyses specifically flag co-administered psychotherapy as a reason effect sizes cannot be attributed to psilocybin by itself.

Particularly relevant for: Trials in this area typically screen out volunteers with significant cardiovascular disease and those with a personal or family history of psychosis or bipolar disorder, so the safety record described here does not extend to those groups.

What to do

Psilocybin remains a Schedule I controlled substance under US federal law. Anyone facing cancer-related distress should discuss options with their oncology and palliative care team, and can look for actively recruiting trials on ClinicalTrials.gov.

Grob 2011 (PMID 20819978); Yu 2021 (PMID 34619818); Ross ML 2025 (PMID 40858059)

This article describes clinical research findings and is not medical advice. It is not a recommendation to use psilocybin, and treatment decisions for cancer-related depression, anxiety, or existential distress should be made with a qualified physician.

For the broader picture of psilocybin's effects on how people relate to death and mortality, see How Psilocybin Changes the Relationship with Mortality. For the quality-of-life outcomes measured in the same patient population, see Psilocybin and Quality of Life in Terminal Cancer Patients.

The Bottom Line

The Hopkins and NYU 2016 trials were not independently lucky results; they were coordinated, back-to-back evidence from different teams using different comparators that converged on the same finding. A single psilocybin session, delivered with psychotherapy in a supervised setting, produced rapid and substantial reductions in cancer-related depression and anxiety, and the NYU cohort's benefits were still measurable at 4.5 years. The evidence for depression is the strongest part of the picture; pooled anxiety results are inconsistent, and the crossover designs, small samples, and imperfect blinding mean the very large reported effect sizes should be read as directionally informative rather than precise. An independent Australian phase 2b trial in 2025 reproduced the pattern — the most meaningful confirmation to date.

Frequently Asked Questions

What did the NYU psilocybin study find for cancer patients?

The 2016 NYU trial enrolled 29 cancer patients and compared a single 0.3 mg/kg psilocybin dose against niacin, both alongside psychotherapy. Before the crossover at 7 weeks, 83% of the psilocybin-first group met antidepressant response criteria on the BDI versus 14% of the niacin-first group. At the 6.5-month follow-up, roughly 60-80% of participants still showed clinically significant reductions in depression or anxiety. The trial also formally measured demoralization and hopelessness — both improved — and 70% of participants rated the session as the single or among the top five most personally meaningful experiences of their lives.

What were the results of the Johns Hopkins psilocybin cancer trial?

The 2016 Hopkins trial enrolled 51 cancer patients and found that at its 6-month follow-up, 78% showed a clinically significant depression response on the GRID-HAMD-17 and 83% an anxiety response on the HAM-A, from a single high-dose psilocybin session. Remission rates were 65% for depression and 57% for anxiety. Secondary outcomes including quality of life, life meaning, optimism, and death anxiety all improved. The intensity of the mystical experience during the session mediated the effect of dose on clinical outcome.

How long do the effects of psilocybin last in cancer patients?

The longest follow-up comes from the NYU cohort. Agin-Liebes and colleagues reassessed 15 of the 16 surviving participants at an average of 3.2 and 4.5 years post-treatment; roughly 60-80% still met clinical response criteria for depression or anxiety, and demoralization, hopelessness, and death anxiety remained reduced. Those participants received no additional psilocybin as part of the study. An important caveat: because the parent trial used a crossover design, every participant eventually received psilocybin, so there is no untreated comparison group at these later timepoints and durability cannot be causally attributed to psilocybin on this evidence alone.

What is the sample size of the Johns Hopkins psilocybin cancer study?

The 2016 Hopkins psilocybin cancer trial enrolled 51 patients with life-threatening cancer and clinically significant depression and/or anxiety. It used a counterbalanced crossover design in which each participant received high-dose psilocybin (22 or 30 mg per 70 kg) in one session and a very low, placebo-like dose (1 or 3 mg per 70 kg) in another, 5 weeks apart. The 51-patient sample was substantially larger than the earlier Grob 2011 pilot (n=12) and the concurrent NYU trial (n=29), making it the largest individual psilocybin cancer RCT at the time of publication.

Did psilocybin help with anxiety in terminal cancer patients?

The individual trials say yes, but the pooled evidence for anxiety is less consistent than for depression. Hopkins found an 83% anxiety response at 6 months, and NYU found 58% anxiolytic response versus 14% on niacin at 7 weeks. Yu's 2021 meta-analysis found psilocybin superior to placebo on both state and trait anxiety, including at 6 months. However, the 2026 Moshfeghinia meta-analysis found the HADS anxiety subscale did not reach statistical significance (p=0.11) and STAI results were inconsistent. The honest summary is that the depression signal is stronger and more replicated than the anxiety signal, and both rest on a small number of small trials.

Sources & References

1. 1RTHM-00445·Ross, Stephen et al. (2016). “Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: a randomized controlled trial..” Journal of psychopharmacology (Oxford.Study breakdown →PubMed →↩
2. 2RTHM-00426·Griffiths, Roland R et al. (2016). “Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial..” Journal of psychopharmacology (Oxford.Study breakdown →PubMed →↩
3. 3RTHM-00397·Grob, Charles S et al. (2011). “Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer..” Archives of general psychiatry.Study breakdown →PubMed →↩
4. 4RTHM-01160·Agin-Liebes, Gabrielle I et al. (2020). “Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer..” Journal of psychopharmacology (Oxford.Study breakdown →PubMed →↩
5. 5RTHM-01425·Ross, Stephen et al. (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.Study breakdown →PubMed →↩
6. 6RTHM-01466·Yu, Chia-Ling et al. (2021). “Psilocybin for End-of-Life Anxiety Symptoms: A Systematic Review and Meta-Analysis..” Psychiatry investigation.Study breakdown →PubMed →↩
7. 7RTHM-02238·Moshfeghinia, Reza et al. (2026). “The effects of psilocybin on psychological distress in cancer patients: a systematic review and meta-analysis..” BMC psychology.Study breakdown →PubMed →↩
8. 8RTHM-02190·Swieczkowski, Damian et al. (2025). “Psilocybin-assisted psychotherapy as a rapid-acting treatment for cancer-related depression and anxiety: Evidence from a network meta-analysis..” International journal of psychiatry in medicine.Study breakdown →PubMed →↩
9. 9RTHM-00096·Griffiths, R R et al. (2006). “Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance..” Psychopharmacology.Study breakdown →PubMed →↩
10. 10RTHM-00949·Ross, Margaret L et al. (2025). “Psilocybin-assisted psychotherapy for depression and anxiety associated with life threatening illness: A phase 2b randomized controlled trial..” General hospital psychiatry.Study breakdown →PubMed →↩
11. 11RTHM-02122·Lapid, Maria I et al. (2025). “Evaluating the effectiveness of psilocybin in alleviating distress among cancer patients: A systematic review..” Palliative & supportive care.Study breakdown →PubMed →↩