Gilgamesh Pharmaceuticals Gets Positive Results on Fast-Acting Psychedelic

Gilgamesh Pharmaceuticals announced the successful completion of its Phase 1 single ascending dose (SAD) trial of GM-2505. In the Phase 1 study, Gilgamesh reported that the GM-2505 patients reached a peak intensity consistent with a full psychedelic experience, while the duration of those effects was limited to 60-90 minutes.

According to the company, GM-2505 is a novel, patented small molecule, short-acting 5-HT2A receptor agonist/5-HT releaser that is expected to have a rapid and durable antidepressant effect. It is expected to produce dramatic changes in human consciousness, perception, emotion, and cognition.

Given the limited number of trained therapists, Gilgamesh believes it will be able to treat more patients than those that only have multi-hour psychedelic treatment options.

“We were thrilled to obtain clinical confirmation of the short half-life and strong psychedelic effects of GM-2505 that were suggested by preclinical data and look forward to advancing this promising therapeutic candidate into patients,” said Andrew Kruegel, PhD, CSO and co-founder of Gilgamesh.

The company believes that GM-2505’s short duration of action will harness the impressive clinical efficacy of other 5-HT2A receptor agonists while better aligning with existing health care infrastructure and clinical workflow, which will broaden patient access in contrast to longer-acting agents such as psilocybin.

“In the Gilgamesh Phase 1 study, a full range of GM-2505 doses have been tested with the highest doses of 15 and 20 milligrams manifesting a full psychedelic effect with minimal effects below 10 milligrams. This provides a basis to move confidently into initial Phase 2a testing in patients with GM-2505,”  Dr. Matthias Liechti said.

Following the successful completion of the Phase 1 SAD trial, Gilgamesh said it will initiate a Phase 2a study in major depressive disorder (MDD) patients during the first quarter of 2024. The Phase 2a study will aim to refine the dosing regimen, confirm safety, and demonstrate an early efficacy signal of GM-2505.

The company said that additional details will be presented at the American College of Neuropsychopharmacology meeting in December.