Clinilabs Drug Development Corporation has commenced subject enrolment in a Phase I/IIa trial of CYB003 to treat major depressive disorder (MDD).

A new psilocybin deuterated analog, CYB003 is being developed by biopharmaceutical company Cybin.

Due to structural similarity with serotonin, CYB003 is claimed to easily trigger the serotonin 5-HT2A receptor.

Cybin has obtained the US Food and Drug Administration clearance for Investigational New Drug application to commence the Phase I/IIa trial by the end of June this year.

With the latest development, CYB003 is the first novel psilocybin analog in the industry to enter clinical trials.

The double-blind, randomised, placebo-controlled trial will analyse CYB003 in people with moderate to severe MDD aged 21 to 55 years.

Subjects will be given two doses of the trial drug with response/remission being evaluated at week three following the first dose and week six after the second dose.

Furthermore, subjects in the trial who are presently receiving selective serotonin reuptake inhibitors will be permitted to remain on their antidepressant treatment.

The trial will use the Montgomery-Asberg Depression Rating Scale to evaluate the quick onset of antidepressant effect on the day of treatment administration. 

In addition, the incremental benefit of a second CYB003 dose when given at week three will be assessed in the trial and offer crucial pharmacokinetics (PK) and safety findings to decide the step forward. 

Clinilabs Strategy and Corporate Development vice-president Jeanine Falinski said: “Clinilabs is honoured to be working with Cybin, an innovator in the development of novel psychedelic therapeutics, to conduct its first-in-human clinical trial of CYB003. 

“We are excited by the potential of these therapeutics and hope that the future is life-changing for individuals suffering from mental illness.”