Clinical stage cannabinoid and psychedelic development company Incannex Healthcare (ASX: IHL) has filed an international patent application as part of the development program for its drug IHL-42X for the treatment of obstructive sleep apnoea.
The application was filed under the Patent Cooperation Treaty and provides Incannex with an opportunity to pursue protection in foreign jurisdictions including key markets of North America, the European Union, Japan and Australia.
It is founded on the claim that IHL-42X’s formulation of registered off-patent pharmaceutical acetazolamide, combined with tetrahydrocannabinol (THC), is a method for the treatment of obstructive sleep apnoea. Granted patents are generally in place for 20 years and afford market exclusivity and enhanced commerciality.
The claim in the patent application is supported by an interim analysis of data from an ongoing phase 2b clinical trial being conducted at the University of Western Australia Centre for Sleep Science.
These results have been kept confidential so that the trial remains blinded, with final results of the double-blind, randomised, placebo-controlled trial to be available next quarter once all subjects have completed treatment and the clinical study report is finalised.
Extension of trial
Incannex has received ethics approval to commence an open label extension study of the phase 2b trial.
The study will assess the therapeutic benefits and tolerability of IHL-42X over an extended timeframe, using patients from the phase 2 trial who have completed their dosage regimen and who have experienced benefits from the drug.
It will comprise six months of daily treatment with IHL-42X, with the primary endpoint being a reduction in each patient’s Apnoea Hypopnea Index (AHI) compared to their original, pre-treatment baseline measurement, which is the same end point in the phase 2 trial but over a longer time frame.
AHI will be assessed during three overnight sleep studies at days 28, 64 and 168, with the aim of a maintaining a reduction over an extended period.
Participants will also be monitored for improvements in alertness, daytime sleepiness, mood, and quality of life every 28 days.
The safety of IHL-42X will be assessed through monitoring of vital signs, serum liver enzymes, blood cell counts and electrolyte levels at each clinic visit.
Incannex managing director Joel Latham said the extension study results will be valuable to the drug’s development.
“Patients who have finished their dosing regimens in the phase 2b trial are now eligible to use IHL-42X every day for an extended period,” he said.
“The data we gather from this program will be invaluable to our ongoing [US Food and Drug Administration] development plan.”
Significant market opportunity
Obstructive sleep apnoea is a major public health problem and represents a significant market opportunity for Incannex.
The condition is characterised by a narrowing (or obstructing) of the upper airway during sleep, which interferes with breathing and interrupts sleep.
The relatively common yet chronic disorder is believed to be underdiagnosed and inadequately treated.
It is understood to contribute to a wide range of serious long-term outcomes including cardiovascular disease, cognitive impairments such as memory loss, poor concentration and judgment, depression, and injury or death due to traffic accidents resulting from excessive daytime sleepiness.
Research from 2019 estimated that obstructive sleep apnoea affects around 936 million adults worldwide and has an annual economic burden in the US alone of US$149.6 billion (A$204.3 billion).
There are currently no registered prescription or over-the-counter medications available for treatment of the condition.
The current stand of care is the CPAP machine; however, it has low rates of compliance due to lack of tolerability.