New York biotech Eleusis has completed a phase 1 trial of the psychedelic drug LSD in healthy older volunteers, setting the stage for a phase 2 trial in Alzheimer’s disease.
LSD – or lysergic acid diethylamide to give it its chemical name – was given in six doses over a three-week period in the trial, and seemed to have no ill effect on the group of 48 volunteers, with an average age of around 63.
Eleusis says the psychoactive properties of LSD stem from its action on the serotonin 5-HT2A receptor, which it thinks is a promising target in Alzheimer’s as these receptors are involved in processes that control memory and cognition.
These receptors decline in the brains of people with Alzheimer’s dementia and the falls seem to correlate with worsening cognitive function.
Earlier studies point to potential benefits for LSD in depression, anxiety, and substance abuse, and Eleusis’ hope is that low dose LSD may also have significant potential in treating Alzheimer’s, says the privately-held biotech.
The trial compared three ‘microdoses’ of LSD – 5, 10 and 20 micrograms – to placebo and found no significant differences between the groups on cardiovascular measures like ECG reading and blood pressure as well as other clinical measures, other than a slight increase in headache.
At the doses tested the psychoactive properties of LSD are below the level that is detectable by the recipient, says Eleusis.
The hypothesis is that LSD could affect multiple pathological processes in Alzheimer’s, including neuroinflammation.
“The study provides reassuring safety data and opens the door for larger scale clinical trials to evaluate the potential therapeutic effects of LSD,” according to Robin Carhart-Harris, head of the Centre for Psychedelic Research at Imperial College London who was involved in the trial.
Other treatments targeting serotonin pathways in Alzheimer’s haven’t proved to be successful – such as Lundbeck and Otsuka’s 5-HT6-targeting drug idalopirdine for example. The entire Alzheimer’s drug development field is littered with failed candidates, so expectations for the LSD project remain firmly in check at the time being.
Nevertheless, there is growing interest in exploring the therapeutic potential of psychoactive drugs most commonly associated with recreational use.
Eleusis’ trial comes after the non-profit Usona Institute launched a phase 2 trial of psilocybin – found in ‘magic mushrooms’ – as a treatment for major depressive disorder.