Incannex Reports Phase 2 Results For IHL-42X, Reducing Sleep Apnea Severity By Up To 83% With Strong Safety Profile

Statistically and clinically significant improvements across key clinical endpoints; IHL-42X reduced AHI by up to 83% from baseline. IHL-42X demonstrates compelling clinical benefit and an outstanding safety profile that exceeded expectations.

NEW YORK and MELBOURNE, Australia, July 30, 2025 (GLOBE NEWSWIRE) -- Incannex Healthcare Inc. (NASDAQ:IXHL) ("Incannex" or the "Company") is excited to share positive topline results from its RePOSA Phase 2 clinical trial evaluating IHL-42X, a novel oral drug candidate for obstructive sleep apnoea (OSA). With over 900 million people affected globally and no approved oral pharmaceutical treatments currently available, IHL-42X's robust efficacy and exceptional safety profile position it as a potential transformative therapy for OSA patients worldwide. The results confirm statistically significant and clinically meaningful improvements across key endpoints assessed in the study, reinforcing IHL-42x's potential as a best-in-class therapy for patients with OSA.

Compelling Clinical Efficacy

The RePOSA Phase 2 trial demonstrated clear statistically and clinically significant improvements across multiple key endpoints for patients receiving IHL-42X compared to placebo, highlighting its potential to reduce OSA severity and enhance patient quality of life:

• Apnoea-Hypopnoea Index (AHI): The low-dose and high-dose IHL-42X groups achieved a statistically significant reduction in percent change in AHI from baseline compared to placebo (p<0.05), the primary measure of OSA severity. Maximum reductions in AHI were observed at up to 83% for the high-dose group and up to 79% for the low-dose group. Notably, 33.3% of patients in the low-dose group and 41.2% in the high-dose group achieved a greater than 30% reduction in AHI, while 13.9% (low-dose) and 14.7% (high-dose) experienced reductions exceeding 50%—demonstrating a strong therapeutic response in a substantial subset of the population.
• Patient Global Impression of Change (PGI-C) Sleep related impairment: The low-dose IHL-42X group showed statistically significant improvement (p<0.05), reflecting meaningful patient-perceived benefits.
• PGI-C Fatigue: Statistically significant improvement in the low-dose group, suggesting enhanced daytime alertness and reduced fatigue.
• Oxygen Desaturation Index (ODI): Both low- and high-dose groups demonstrated statistically significant improvements, indicating better oxygenation during sleep.
• Patient-Reported Outcomes: IHL-42X led to clinically significant improvements in patient-reported outcome measures, including the Functional Outcomes of Sleep Questionnaire-10 (FOSQ-10), PROMIS Sleep-Related Impairment 8a (PROMIS-SRI 8a), PROMIS Fatigue 7a, and Epworth Sleepiness Scale (ESS) in both low- and high-dose groups, demonstrating enhanced sleep quality, reduced daytime fatigue, and improved daily functioning for patients with OSA.
• Polysomnography (PSG) Metrics: IHL-42X drastically improved objective sleep parameters as measured by PSG.
  • Wake After Sleep Onset (WASO): Reduced by 29.8% in the high-dose arm, meaning patients spent less time awake during the night.
  • AHI During Supine Sleep: Decreased by 30.3% in the high-dose arm, a critical improvement given supine sleep exacerbates apneic events.

These results collectively demonstrate IHL-42X's ability to address both objective and subjective aspects of OSA, offering compelling clinical benefits to patients.

Outstanding Safety Profile

IHL-42X was well tolerated across both low- and high-dose cohorts. No serious adverse events were reported during the treatment period, and treatment-emergent adverse effects (TEAEs) were infrequent, with the majority being mild or moderate in severity. This excellent safety profile supports IHL-42X's potential for broad patient use.