Incannex Healthcare Ltd, a clinical-stage pharmaceutical company developing medicinal cannabinoid pharmaceutical products and psychedelic medicine therapies, has received approval from the US Food and Drug Administration (FDA) for an Investigational New Drug (IND) opening pivotal IHL-42X phase 2/3 clinical trial for obstructive sleep apnea in the United States as planned.
Incannex submitted the IND application on July 20, and the FDA completed its review of the substantial application package during the allocated 30-day period. Incannex received communication that the IND opening clinical trial was deemed safe to proceed following an assessment of the trial protocol, lead trial investigators, and a risk-benefit analysis of the trial and prospective product.
The IND opening trial will assess the effect of IHL-42X in obstructive sleep apnea patients who are non-compliant, intolerant, or naïve to positive airway pressure treatment, such as that administered by CPAP devices.
Incannex will continue the start-up process for the phase 2/3 clinical trial. This will include the finalization of institutional review board applications and submissions for the lead clinical trial sites. Site selection, approvals, and institutional review board submission for additional study sites will continue in parallel.
In the IND opening phase 2/3 clinical trial, participants will receive one dose of IHL-42X, dronabinol, acetazolamide, or placebo for the entirety of the trial. All participants will complete daily surveys on their sleep quality and attend monthly clinic visits to assess functional outcomes of sleep, cognitive function, and other measures of safety and efficacy.
Every three months, overnight polysomnography will be conducted to determine the effect of treatment on the patients’ apnea-hypopnea index along with a range of other sleep parameters. All drug treatments will be compared to placebo.
IHL-42X is a synergistic composition of dronabinol, a synthetic form of tetrahydrocannabinol (THC), and acetazolamide, a carbonic anhydrase inhibitor. Results from a phase 2 proof of concept clinical trial undertaken by Incannex were released in 2022. Incannex observed that IHL-42X reduced the average apnoea-hypopnoea index by an average of 50.7% versus baseline assessments and 25% of participants experienced greater than an 80% reduction in the AHI.
No serious treatment-emergent adverse events were reported during the clinical trial. Furthermore, THC concentrations in blood were below the limits for impaired driving the morning after nocturnal dose administration of IHL-42X.