Incannex meets with US FDA on development of IHL-42X to treat obstructive sleep apnoea

Clinical-stage cannabinoid pharmaceutical development company Incannex Healthcare (NASDAQ: IXHL) (ASX: IHL) has completed a pre-investigational new drug application (pre-IND) meeting with the US Food and Drug Administration (FDA) to discuss the development of its drug candidate IHL-42X.

The drug is a fixed dose combination of dronabinol and acetazolamide and has been designed as a tablet for the treatment for obstructive sleep apnoea (OSA) in adults.

Incannex submitted the pre-IND meeting package and request in February, which included an overview of the development program and specific questions relating to regulatory requirements for opening an investigational new drug (IND) application.

An IND is required to conduct clinical trials in the US and ensures that trials are designed to meet the data requirements necessary for FDA marketing approval.

Constructive and supportive

Incannex said the written responses, and those provided in a teleconference with FDA representatives, were “constructive and supportive”, with interest in the project underpinned by the significant cohort of people diagnosed with OSA and the absence of pharmacological treatment solutions.

There are no registered drugs on the market for the treatment of OSA and the current best treatment option is the CPAP machine, but it has low patient compliance due to various factors, including discomfort.

The FDA provided guidance on the company’s long-term development strategy including specific parameters to demonstrate safety and efficacy in phase 2 and phase 3 pivotal studies.

Incannex has said it would use the guidance to adjust its clinical trial protocols to generate the data required for a new drug application (NDA).

No animal studies

In a decision which will save Incannex time and cost, the FDA agreed that the company does not need to conduct studies in animals.

In particular, it confirmed that animal toxicology and animal pharmacokinetic (PK) studies are not required for opening an IND for IHL-42X.

Incannex said the next step for the development of IHL-42X would be the adjustment of clinical trial designs and arrangement of operational imperatives needed to open an IND with FDA.

Potential therapy

Incannex chief scientific officer Dr Mark Bleackley said the company was encouraged by FDA’s interest in IHL-42X as a potential therapy for OSA.

“The feedback provided on the overall proposed development program was positive and [FDA’s] responses to specific questions we posed will allow us to revise our clinical trial protocols to ensure we are running highly-efficient studies that generate the type and amount of data the FDA will require in a future marketing application,” he said.

“The results from the pre-IND meeting will shape the IHL-42X development program over the coming months.”

Proof-of-concept trial

Last year, Incannex completed a phase 2 proof-of-concept clinical trial to assess IHL-42X in patients with OSA.

Preliminary results show that 60% of trial participants experienced a reduction of more than 55% in their apnoea-hypopnea index (AHI) during at least one treatment compared to baseline.

Approximately 20% of participants experienced an AHI reduction of greater than 80%.

Incannex expects the complete clinical study report to be released next month.