Nature Mental Health
May 1, 2026
S. Parker Singleton, Brooke L. Sevchik, Analiese Lahey et al.
2 citations
A living systematic review and meta-analysis of 15 randomized controlled trials (801 participants) found that psilocybin-assisted therapy substantially reduces depressive symptoms compared to control conditions, with a standardized mean difference of −0.90 (Hedges’ g). The analysis included 12 trials (585 participants) in the primary model. Many studies had small sample sizes or risk of bias. The review is maintained as a living resource with an open-data database and online dashboard that will be updated as new evidence emerges.
Psychotherapy and Psychosomatics
June 12, 2026
Thorsten Barnhofer, Maria Niemi, Johannes Michalak et al.
1 citation
For adults with difficult-to-treat depression—those who have not responded to prior treatments, have treatment-resistant depression, or have a chronic course—mindfulness-based cognitive therapy (MBCT) is likely superior to usual care, reducing depressive symptoms by a standardized mean difference of -0.40 at post-treatment and -0.41 at medium-term follow-up. There was a 92% and 85% probability, respectively, that these benefits exceeded a minimal important difference. However, MBCT did not show clear superiority over other active psychosocial interventions, and no robust moderators of outcome were identified across baseline severity, chronicity, or comorbidity.
medRxiv Preprint Server
March 27, 2026
Brooke L. Sevchik, S. Parker Singleton, Analiese Lahey et al.
preprint
A living systematic review and meta-analysis of six randomized controlled trials with 286 participants found that MDMA-assisted therapy reduces PTSD symptoms more than control conditions (Hedges' g = -0.71). More dosing sessions and higher cumulative doses were linked to larger effects. MDMA also led to higher response (risk ratio 1.35) and remission (risk ratio 2.25) rates. Most studies had low risk of bias per Cochrane guidelines, though issues like expectancy and functional unblinding remain. The evidence was rated low certainty using GRADE, and the authors note more trials are needed.
European Neuropsychopharmacology
March 12, 2026
Natalia E. Fares-Otero, Yuki Furukawa, Marit Sijbrandij et al.
A systematic review and meta-analysis of randomized controlled trials found that MDMA-assisted therapy (MDMA-AT) was associated with reductions in PTSD symptom severity and dissociative symptoms, and may improve functioning, compared with control conditions. No clear benefit was observed for depressive symptoms. The analysis included 8 trials with 298 participants for the primary outcome. However, the overall certainty of the evidence was very low due to high risk of bias in outcome measurement, deviations from intended interventions, small sample sizes, and lack of active controls in most studies. Larger, higher-quality trials with active controls and long-term follow-up are needed to determine efficacy.
medRxiv
August 16, 2025
S. Parker Singleton, Brooke L. Sevchik, Analiese Lahey et al.
preprint
Psilocybin-assisted therapy produces substantial reductions in depressive symptoms compared to control conditions, according to a systematic review and meta-analysis of 12 randomized controlled trials with 711 participants. The pooled effect size was large (Hedges' g = –0.91), and effects appeared rapidly and remained consistent over several weeks. However, many studies had small sample sizes or risk of bias, and waitlist-controlled or crossover designs contributed heterogeneity. The review provides a living open data resource that will be updated as new evidence emerges.