A report on the new study was published on Feb. 15, 2022 in the Journal of Psychopharmacology. Below is a news release from Johns Hopkins Medicine.
Previous studies by Johns Hopkins Medicine researchers showed that psychedelic treatment with psilocybin relieved major depressive disorder symptoms in adults for up to a month. Now, in a follow-up study of those participants, the researchers report that the substantial antidepressant effects of psilocybin-assisted therapy, given with supportive psychotherapy, may last at least a year for some patients. “Our findings add to evidence that, under carefully controlled conditions, this is a promising therapeutic approach that can lead to significant and durable improvements in depression,” says Natalie Gukasyan, M.D., assistant professor of psychiatry and behavioural sciences at the Johns Hopkins University School of Medicine.
The researchers reported that psilocybin treatment in both groups produced large decreases in depression, and that depression severity remained low one, three, six and 12 months after treatment.
Depressive symptoms were measured before and after treatment using the GRID-Hamilton Depression Rating Scale, a standard depression assessment tool, in which a score of 24 or more indicates severe depression, 17–23 moderate depression, 8–16 mild depression and 7 or less no depression. For most participants, scores for the overall treatment decreased from 22.8 at pretreatment to 8.7 at one week, 8.9 at four weeks, 9.3 at three months, 7 at six months and 7.7 at 12 months after treatment.
Participants had stable rates of response to the treatment and remission of symptoms throughout the follow-up period, with 75% response and 58% remission at 12 months.
“Psilocybin not only produces significant and immediate effects, it also has a long duration, which suggests that it may be a uniquely useful new treatment for depression,” says Roland Griffiths, Ph.D., the Oliver Lee McCabe III, Ph.D., Professor in the Neuropsychopharmacology of Consciousness at the Johns Hopkins University School of Medicine, and founding director of the Johns Hopkins Center for Psychedelic and Consciousness Research. “Compared to standard antidepressants, which must be taken for long stretches of time, psilocybin has the potential to enduringly relieve the symptoms of depression with one or two treatments.”
The researchers emphasize that further research is needed to explore the possibility that the efficacy of psilocybin treatment may be substantially longer than 12 months. Johns Hopkins is one of the sites of a national multisite randomized, placebo-controlled trial of psilocybin for major depressive disorder.