Incannex Healthcare on Wednesday said its investigational psychedelic psilocybin met the primary endpoint, demonstrating it can reduce Hamilton anxiety scores by more than nine points versus placebo.
Pictured: Anxious man with his head in his hands/iStock, gorodenkoff
Incannex Healthcare on Wednesday unveiled topline results from the Phase II Psi-GAD1 study of its investigational psychedelic compound psilocybin, eliciting significant symptom improvement in patients with generalized anxiety disorder.
At six weeks after the final dosing, patients treated with psilocybin had a score of 16.8 on the Hamilton Anxiety Rating Scale (HAM-A)—a validated tool used to measure the severity of anxiety symptoms—versus 29.5 points at baseline.
The 12.8-point decrease in HAM-A score after psilocybin treatment was significantly greater than the 3.6-point reduction in the placebo group, with a p-value less than 0.0001, according to Incannex’s announcement.
Following treatment with psilocybin, 44% of patients demonstrated a clinically meaningful improvement in anxiety symptoms, quantified by a 50% drop in HAM-A scores. Moreover, 27% of patients achieved full disease remission, a rate five times higher than that in the placebo group.
In terms ofsafety, psilocybin was well-tolerated for the treatment of generalized anxiety disorder, inducing only mild and moderate adverse events. One patient withdrew from the study.
Incannex’s shares skyrocketed 130% in premarket trading on Wednesday in reaction to the news, according to Seeking Alpha.
CEO Joel Latham said in a statement that the company is “thrilled” with these results from Psi-GAD1, which is the “first time psilocybin has been investigated for treatment of generalized anxiety disorder.”
“The reduction in HAM-A scores we have observed are far greater [than] those reported from trials on established medicines for treatment of anxiety,” Latham said, adding that “this treatment method has the potential to improve the quality of life for millions of people suffering from generalized anxiety disorder.”
Incannex is planning to run large-scale controlled trials for psilocybin. The drug product candidate will be called PSX-001. The company has also designed the follow-up Phase IIb trial dubbed PsiGAD2, which it plans to conduct across various sites in the U.S. and U.K.
Psilocybin is a psychedelic drug that works by activating serotonin type 2A receptors to induce a hallucinatory effect, which in turn can help counter depressive and anxious symptoms. However, like other psychedelics, psilocybin has not been extensively studied.
Another company in the psychedelic space is MindMed, which in December 2023 posted data from the Phase IIb trial of its LSD-based candidate MM-120, demonstrating a significant benefit on generalized anxiety disorder. Treated patients saw a 7.6-point decrease in scores on the Hamilton scale compared with placebo.
In January 2024, CMO Dan Karlin told BioSpace that the biotech is looking to move the candidate into Phase III studies, which it plans to start in the second half of 2024.
Tristan Manalac is an independent science writer based in Metro Manila, Philippines. Reach out to him on LinkedIn or email him at tristan@tristanmanalac.com or tristan.manalac@biospace.com.
