Incannex Healthcare Inc.

IHL Therapeutics

Company profile

IHL Therapeutics is a clinical-stage biopharmaceutical company developing oral fixed-dose combination therapies and psychedelic-assisted treatments for serious chronic conditions. Lead assets include:

• IHL-42X: a fixed-dose combination of dronabinol and acetazolamide for obstructive sleep apnea (OSA).
• PSX-001: oral synthetic psilocybin for generalized anxiety disorder (GAD), intended for use with structured psychotherapy.
• IHL-675A: a fixed-dose combination of cannabidiol (CBD) and hydroxychloroquine sulfate for inflammatory conditions, initially targeting rheumatoid arthritis (RA).

The company’s regulatory and development strategy emphasizes U.S. pathways (including 505(b)(2) and Fast Track), intellectual property protection, and potential global expansion after U.S. approval.

Lead program — IHL-42X (obstructive sleep apnea)

• Mechanism: an oral fixed-dose combination of dronabinol (THC) and acetazolamide designed to target two pathways involved in the intermittent hypoxia/hypercapnia characteristic of OSA.
• Clinical progress:
  • RePOSA Phase 2/3 trial: Phase 2 portion completed July 2025; FDA Fast Track designation granted December 2025.
  • Phase 2 results showed reductions in apnea-hypopnea index (AHI), improvements in patient-reported outcomes, and favorable tolerability.
• Next study — DReAMzz (dose confirmation, crossover design):
  • Commenced May 2026; screening began July 2026; currently enrolling.
  • Design: three 4-way crossover arms per study, testing 9 dose combinations across three dronabinol levels (2.5, 5, 7.5 mg) and three acetazolamide levels (125, 250, 375 mg).
  • Sites: approximately 14 U.S. sites; total ~120 subjects across all three crossover studies.
  • Primary endpoint: change in end-of-treatment AHI. Expected completion: mid-2027; results will inform Phase 3 design.
• Manufacturing: Procaps Group engaged for fixed-dose formulation; initial supply for DReAMzz produced and prepared toward NDA manufacturing readiness.
• Regulatory and market context: FDA Fast Track status and potential 505(b)(2) pathway; regulatory strategy includes possible expansion to EU/UK/Japan/Australia/Canada after U.S. approval.

PSX-001 (generalized anxiety disorder)

• Product concept: oral psilocybin combined with a structured psychotherapy program (preparation, dosing sessions, integration).
• Phase 2 program — PsiGAD1 (Australian Phase 2 exploratory proof-of-concept):
  • Design: randomized, triple-blind, active-placebo-controlled; two dosing sessions plus up to 11 psychotherapy sessions over ~10 weeks.
  • Results (August 2025): met the primary endpoint with an average 12.8-point reduction in HAM-A scores from baseline sustained over ~11 weeks. Greater than 50% HAM-A reduction observed in 44.1% of PSX-001–treated patients versus 27% in placebo. Seventy-three patients enrolled; no serious adverse events reported; one discontinuation.
  • Secondary outcomes: improvements on GAD-7, Sheehan Disability Scale, PHQ-9, and quality-of-life measures; tolerability described as favorable.
• Development and commercialization:
  • IND cleared by the FDA; next steps include design choices for a Phase 2b study to further differentiate PSX-001 in the GAD market.
  • cGMP manufacturing work with Ardena US LLC.
  • Commercialization plan includes MMA Clinics, a 50:50 joint venture with Mind Medicine Australia established June 2025 to operate a psychedelic-assisted therapies clinic in Melbourne.

IHL-675A (inflammatory conditions; initial focus on RA)

• Composition: CBD plus hydroxychloroquine sulfate (HCQ).
• Clinical progress:
  • Phase 1 completed in healthy volunteers (three cohorts of 12, total 36 participants). The study compared pharmacokinetics and safety with Epidiolex (CBD) and Plaquenil (HCQ); IHL-675A was well tolerated and produced PK profiles consistent with a fixed-dose combination.
  • A planned 128-patient Phase 2 RA study was initiated but recruitment challenges led to termination of the Australian RA trial before completion.
• Strategy: continued assessment of development options for IHL-675A while prioritizing IHL-42X and PSX-001; potential expansion to other inflammatory indications has been discussed.

Intellectual property

• IHL-42X portfolio: 2 granted patents and 18 pending US/EU/JP/other applications as of September 1, 2026. Granted patents expire in 2041; pending applications could extend protection into 2041–2043 if issued.
• Cannabinoid combination patents: as of September 23, 2026, 5 granted patents and 23 pending applications, with expirations generally between 2040 and 2043.
• Jurisdictions covered include the U.S., Australia, Canada, Colombia, Europe (EPO), Israel, New Zealand, UAE, Hong Kong, and Japan.
• Patent strategy targets compositions, methods of use, formulations, and manufacturing processes.

Manufacturing, partnerships, and commercialization

• Manufacturing partners:
  • IHL-42X: Procaps Group for development and manufacture of the fixed-dose formulation.
  • PSX-001: Ardena US LLC for cGMP psilocybin drug product manufacture.
• Commercialization and clinics:
  • MMA Clinics: joint venture with Mind Medicine Australia (June 2025) to operate a psychedelic-assisted therapies clinic in Melbourne as part of the PSX-001 commercialization model.
• Regulatory environment:
  • Assets include controlled substances (cannabinoids, psilocybin) with ongoing DEA and international regulatory considerations.
  • U.S. regulatory pathways include 505(b)(2) and accelerated programs such as Fast Track, Breakthrough Therapy, and Priority Review, as well as the Commissioner’s National Priority Voucher (CNPV) pilot.
  • Compliance programs address GMP, GLP, GCP, REMS considerations, and post-approval safety surveillance.

Market context and opportunity

• OSA: an addressable global market for OSA medical devices estimated at US$8.2 billion with a 7.33% CAGR (2024–2029). IHL-42X targets an oral pharmacologic alternative for patients with CPAP non-compliance, device intolerance, or non-obese phenotypes.
• GAD: the U.S. treatment market for anxiety disorders was around US$21 billion in 2023. PSX-001 aims to differentiate through a psychedelic-assisted psychotherapy model.
• RA and inflammatory diseases: the U.S. RA market was approximately US$25.37 billion in 2023 and is projected to exceed US$31.58 billion by 2033. Broader inflammatory indications (COPD, asthma, IBD) represent additional potential opportunities for IHL-675A if development advances.
• Competitive landscape: the company competes with other cannabinoid and psychedelic programs, large pharmaceutical companies, academic groups, and biotech entrants. The company emphasizes two-drug synergy in fixed-dose combinations and regulatory strategies to achieve differentiation.

Selected clinical trial metrics

• RePOSA (IHL-42X, Phase 2 portion): 121 subjects across 16 U.S. sites.
• DReAMzz (IHL-42X, dose-confirmation): ~120 subjects across ~14 U.S. sites.
• PsiGAD1 (PSX-001, Phase 2 GAD): 73 patients in Australia.
• IHL-675A Phase 1: 36 healthy volunteers (three cohorts of 12).

Upcoming milestones and focus

• IHL-42X: complete DReAMzz (expected mid-2027) to inform Phase 3 design and pursue NDA pathways after dose confirmation.
• PSX-001: finalize Phase 2b or next-stage design, continue cGMP manufacturing, and advance clinical adoption channels through MMA Clinics.
• IHL-675A: reassess development strategy for RA and other inflammatory indications in light of the terminated RA trial.
• IP and regulatory: expand patent coverage where appropriate and pursue applicable priority programs while managing controlled-substance regulatory requirements in the U.S. and abroad.