Psilocybin for depression and anxiety in people with cancer: the 2016 Johns Hopkins trial
The question
A cancer diagnosis can bring deep fear, sadness and worry about death. For many patients, this distress lasts, and standard treatments do not always help enough.
Researchers at Johns Hopkins wanted to know whether one or two carefully guided psilocybin sessions could reduce depression and anxiety in people with life-threatening cancer, and whether any benefit would still be there six months later.
Who took part and what happened
Fifty-six people were randomized (assigned by chance to groups), and 51 completed at least one session and were included in the results. Their average age was 56, and about half were women. All had a cancer diagnosis that could threaten their life; about two in three had cancer that had come back or spread. All had been diagnosed with a depression- or anxiety-related condition, such as major depression, generalized anxiety, or ongoing distress linked to their illness.
The study was double-blind (neither patients nor the staff running the sessions were told the dose) and used a crossover design (everyone eventually received both conditions, in a different order). Each person had two sessions about five weeks apart. One used a very low dose of psilocybin (1 or 3 mg per 70 kg of body weight), meant to act like a placebo. The other used a high dose (22 or 30 mg per 70 kg). Half got the high dose first; half got the low dose first.
Two trained monitors stayed with each person throughout every session. Before the first session, patients had on average three preparation meetings (about 8 hours in total), plus more meetings after each session. Depression and anxiety were rated by clinicians and by the patients themselves at the start, about five weeks after each session, and at a six-month follow-up.
What they found
- Clear difference after the first session. About five weeks after session one, 92% of people who received the high dose first showed a clinically meaningful drop in depression, compared with 32% of those who got the low dose first. For anxiety, the figures were 76% versus 24%.
- Six months later. At follow-up, 78% of participants still showed a meaningful drop in depression and 83% in anxiety. About 65% no longer met the threshold for depression, and 57% for anxiety. Put simply, about 4 in 5 people still felt clearly better.
- Broader changes. The high dose was also linked to better quality of life, a stronger sense of meaning, more optimism, and less fear of death.
- Personal meaning. At six months, about 67% rated the high-dose session among the five most meaningful experiences of their life, and about 83% reported moderately or greatly increased well-being or life satisfaction.
- Mystical experience mattered. People who had a stronger mystical-type experience (a sense of unity, peace and deep meaning) tended to improve more.
There were side effects. During high-dose sessions, blood pressure rose for a while in 34% of sessions, nausea or vomiting happened in 15%, and periods of anxiety in 26%. Some kind of psychological discomfort occurred in 32% of high-dose sessions. No serious adverse events were linked to psilocybin.
What this study does not tell us
- Blinding was hard. High-dose psilocybin has strong, obvious effects. Participants and staff may often have been able to tell which session was which, and expectations may have influenced results.
- The six-month results have no comparison group. Because of the crossover design, everyone had received the high dose by then. So the long-term numbers show that improvement lasted, but not how much was due to psilocybin itself.
- The "placebo" was still psilocybin. The low dose may not have been fully inactive.
- A narrow group. 94% of participants were white and more than half had a postgraduate degree. Results may differ in other groups.
- Intensive support. Patients were medically screened and had many hours of preparation and follow-up with trained staff. That support is part of what was tested.
Why it matters
Together with a similar trial published at the same time from New York University, this study is one of the most cited pieces of evidence that psilocybin, given with careful preparation and support, may ease emotional distress in people facing serious illness.
It was still a small study in a very controlled setting. Larger and more diverse trials are needed to see whether these results hold up.
This is a summary of published research for general information. It is not medical advice. The study took place in a clinical research setting with medical screening and professional support.
Source: Griffiths, R. R., Johnson, M. W., Carducci, M. A., Umbricht, A., Richards, W. A., Richards, B. D., Cosimano, M. P., & Klinedinst, M. A. (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, 30(12), 1181–1197. doi:10.1177/0269881116675513 · PubMed · Full text
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