Table 1.
Open label studies investigating psilocybin in the treatment of major depressive disorder
| Author (yr) |
Subjects | Design | Allocation | Sample size | Mean age | Length | Intervention | 1° outcome measure | Results |
|---|---|---|---|---|---|---|---|---|---|
| Carhart-Harris et al. [29] (2016) | TRD | Single arm | Psilocybin only | 12 | 42.7 | 12 wk | Two oral psilocybin capsule (10 mg and 25 mg, 7 days apart) | Subjective intensity of psilocybin’s effects (0−1) | Low-dose session: 0.51 (SD 0.36) High-dose session: 0.75 (SD 0.27) |
| Carhart-Harris et al. [30] (2018) | TRD | Extension of Carhart-Harris (2016) | Psilocybin only | 20 | 44.1 | 6 mo | Same as Carhart-Harris (2016) | QIDS-SR16 | Improvement began 1 wk after psilocybin and maintained at 6 mo |
| Lyons and Carhart-Harris [31] (2018) | TRD | Extension of Carhart-Harris (2016) | Psilocybin CG |
15 15 |
45.4 37.6 |
1 wk | Psilocybin = same as Carhart-Harris (2016) CG = healthy subjects |
BDI and POFLE | Depression and negative cognitive bias improved after psilocybin |
| Roseman et al. [32] (2018) | TRD | Extension of Carhart-Harris (2016) | Psilocybin only | 20 | 44.7 | 6 mo | Same as Carhart-Harris (2016) | ASC | Psilocybin-induced high mystical experience and low anxiety predicted positive long-term treatment outcome |
| Davis et al. [33] (2021) | MDD | Waiting list controlled RCT | Psilocybin Waiting |
15 12 |
43.6 35.2 |
4 wk | Two psilocybin capsule sessions (20 mg/70 kg and 30 mg/70 kg) | GRID-HAMD | Significantly more improved in psilocybin group |
| Gukasyan et al. [34] (2022) | MDD | Extension of Davis (2021) | Psilocybin only | 27 | 39.8 | 12 mo | Same as Davis (2021) | GRID-HAMD | GRID-HAMD improved over 12 mo |
1°, primary; ASC, altered states of consciousness; BDI, Beck’s depression inventory; CG, control group; DB, double blinded; GRID-HAMD, GRID Hamilton rating scale for depression; HAM-D 17, 17-item Hamilton depression rating scale; MADRS, Montgomery–Åsberg depression rating scale; MDD, major depressive disorder; POFLE, prediction of future life events task; QIDS-SR16, 16-item quick inventory of depressive symptoms; RCT, randomized clinical trial; TRD, treatment resistant depression; SD, standard deviation.