Medicinal cannabinoid and psychedelic therapies development company Incannex Healthcare (ASX: IHL) has received approval from Bellberry Human Research Ethics Committee (HREC) to conduct a Phase 2 clinical trial of drug candidate IHL-675A at the premises of Emeritus Research in Victoria, Australia.
The pivotal trial will assess the safety and efficacy of IHL-675A as a proprietary anti-inflammatory combination drug for use on patients with rheumatoid arthritis.
It follows animal study observations of IHL-675A substantially reducing inflammatory disease scores to a greater extent than hydroxychloroquine sulphate (HCQ), which is a common long-standing prescription drug for rheumatoid arthritis (called “Plaquenil”) with a considerable market profile.
It is Incannex’s hope that IHL-675A will continue to outperform Plaquenil in observations in this extensive Phase 2 efficacy trial.
The trial will assess the effect of IHL-675A on pain and function by utilising patient reported outcomes, disease scores and inflammatory biomarker analyses over a 24-week period.
It will include a sub-study examining joint damage via MRI (magnetic resonance imaging).
Patients will be assessed for eligibility in the sub-study based on their rheumatoid arthritis MRI score (RAMRIS) at screening.
Trial management
The trial will be managed by Australian and US contract research organisation Avance Clinical, which will engage up to 10 sites across Australia and New Zealand and recruit a total of 128 patients with ongoing pain and reduced function while on stable treatment for rheumatoid arthritis.
Patients will be randomised to either a IHL-675A, CBD alone, HCQ alone or placebo group with the primary endpoint being pain and function relative to baseline determined via scores on the industry-standard RAPID3 assessment at the 24-week mark.
They will use electronic devices to record their pain and function outcomes daily via questionnaires on fatigue, joint stiffness and quality of life.
The results will establish the safety and efficacy of IHL-675A in rheumatoid arthritis patients and contribute to the combination rule assessment in a 505(b)2 new drug application dossier with the US Food and Drug Administration.
Welcoming the approval
Incannex chief scientific officer Dr Mark Bleackley welcomed the HREC approval.
“HREC approval for our Phase 2 trial is a key step in the development of IHL-675A for the treatment of pain and reduced function associated with rheumatoid arthritis,” he said.
“We look forward to working with Emeritus and Avance to assess the effect of [the drug] in this patient population.”
Phase 1 study
The Phase 2 trial follows a successful Phase 1 study whereby active pharmaceutical ingredients cannabidiol (CBD) and HCQ were absorbed from the fixed dose combination IHL- 675A.
The drug was observed to be well tolerated, with no adverse events of concern.
Prior to commencing clinical trials, Incannex observed positive results from an animal model of rheumatoid arthritis which showed the drug to be more effective at reducing arthritis across multiple assessments (including clinical score, paw volume, pannus score, total histology score and serum cytokine levels) than the rodent equivalent of the standard dose of HCQ or equivalent doses of CBD.
“The reduction in disease assessments achieved by IHL-675A was up to 3.52 times that observed for HCQ alone at the standard dose,” Dr Bleackley said.
“These promising observations led us to prioritise rapid clinical assessment, particularly given that HCQ, under the brand name Plaquenil, is a common treatment prescribed for rheumatoid arthritis.”
