The magic mushroom compound psilocybin appeared to be slightly more effective than the selective serotonin-reuptake inhibitor escitalopram (Lexapro) in a small study recently published in NEJM.
In the Phase 2 study, which tracked 59 patients over six weeks, the psilocybin group had an approximately 8-point average drop in the Quick Inventory of Depressive Symptomatology (Self-Report) questionnaire with 16 questions (QIDS-SR16). The 29 patients had a 6-point reduction on the 27-point scale. Higher scores on the scale correlate to more severe depression.
The researchers concluded that there was not “a significant difference in antidepressant effects between psilocybin and escitalopram” in the study. Secondary outcomes, however, tended to favor psilocybin over escitalopram. The researchers added that more studies are needed to evaluate psilocybin against conventional antidepressants.
The study was performed at Imperial College London.
Another paper in NEJM concluded that care is needed when interpreting the study results. “Heterogeneity among patients, who volunteered for the trial in response to advertisements, and uncertainty regarding the appropriate therapeutic dose range and frequency of administration of psilocybin may have influenced the results,” concluded psychiatrist Dr. Jeffrey A. Lieberman.
One point of note regarding the Phase 2 trial is the fact that both groups received psilocybin. The first group received two 25-mg doses of psilocybin three weeks apart and six weeks of daily placebo pills. The second group received daily escitalopram. That placebo group also received two 1-mg doses of psilocybin at the same interval as the first cohort.
Both cohorts were told they would receive psilocybin.
Both groups received psychological support.
Psilocybin is not generally considered psychoactive at doses of less than 3 mg, according to the Drug Policy Alliance. In research settings, psilocybin dosing is typically in the range of 14–30 mg.
Escitalopram can take as long as four to six weeks to begin having a full effect on patients.
Several companies have explored the use of psychedelics in clinical trials to treat conditions ranging from treatment-resistant depression and post-traumatic stress disorder to opioid- and alcohol-use disorders.
The mechanism of how psilocybin and other psychedelics can treat depression is unclear.
In general, researchers have ramped up studies on psychedelic drugs in the past decade, testing their potential to treat depression, anxiety and other conditions.
Researchers are also developing compounds derived from psychedelics designed to have a pharmacologic but not mind-altering influence.
Filed Under: clinical trials, Drug Discovery