Incannex doses first patient in Phase 2 DReAMzz trial of IHL-42X

Incannex Healthcare Inc. announced on August 25, 2026 that the first patient has been dosed in the DReAMzz Phase 2 dose-optimization study of IHL-42X, an oral fixed-dose combination therapy the company is developing for obstructive sleep apnea.¹

The announcement builds on earlier data. In the prior Phase 2 RePOSA study, IHL-42X showed statistically significant reductions in apnea-hypopnea index compared with placebo, with individual reductions as high as 83% and what the company described as an exceptional safety profile.¹ Over the past year, Incannex has reported those RePOSA results, received Fast Track designation from the FDA, and advanced its regulatory strategy through FDA engagement.¹

On trial logistics, all 14 DReAMzz sites now have Institutional Review Board approval to conduct the study.¹ Incannex has set up a network of 14 clinical trial sites across the United States to run DReAMzz.¹ The company said drug product has been manufactured, regulatory and operational preparations are complete, and sites have moved from patient screening to dosing the first patient.¹

The trial's purpose, per the release, is a Phase 2 crossover study meant to further define the dose-response profile of IHL-42X and help select doses for later-stage development.¹ It will look at objective sleep measures along with patient-reported outcomes to help shape the planned Phase 3 program.¹

On the drug itself, IHL-42X combines dronabinol and acetazolamide in a single oral formulation aimed at obstructive sleep apnea.¹ Fast Track designation is intended to speed development and review of treatments for serious conditions with unmet need, and gives sponsors more frequent FDA interactions and potential access to expedited review tools.¹