DReAMzz- Dronabinol and Acetazolamide Medication for Sleep Apnea (ZZ). Dose Confirmation Crossover Study for IHL-42X in Subjects With Obstructive Sleep Apnea.

Participants will be excluded from the study if they satisfy any of the following criteria at screening, unless otherwise stated:

1. Body mass index (BMI) \>40 kg/m2 (men) and \>42 kg/m2 (women).

2. Diagnosed obesity hypoventilation syndrome or hypercapnia.

3. PAP-compliant, defined by use of PAP for ≥4 hours for at least 63 nights during the consecutive 90-day period.

4. Current use of custom-made oral appliances (mandibular advancement device, tongue retaining device, or mouth guard) or hypoglossal nerve stimulation devices. Devices must not be used for the duration of the study.

5. Maxillomandibular advancement, upper airway, or bariatric surgery within the last 6 months prior to first administration of the study drug; or participants who are planning surgical treatment.

6. Have commenced glucagon-like peptide-1 receptor agonist therapy within the last 6 months.

7. Use of benzodiazepines, sedative-hypnotics or stimulants (Anatomical Therapeutic Chemical \[ATC\] N06B, N05C, N05BA, N03AE, and N01AF categories) to treat insomnia, OSA, and other sleep disorders, or other disorders that require the drug to be taken prior to sleep.

8. Use of other prescription medications to treat insomnia.

9. Pierre Robin, Treacher Collins, or other craniofacial malformation syndrome, or grade ≥3 tonsillar hypertrophy.

10. Respiratory and neuromuscular diseases that could interfere with the results of the trial in the opinion of the investigator.

11. Known allergic or other severe reaction to cannabis products with previous use.

12. Known allergic reaction to sesame oil.

13. Known allergic reaction to acetazolamide.

14. Pregnant or breastfeeding.

15. Current illicit drug abuse (within the last 6 months prior to screening); "abuse" has some subsets that are objective and some that require investigator judgement; questions should be discussed with the medical monitor or with the sponsor

1. An objective subset includes consumption of substances that are "illicit", i.e., not legal per local laws

2. Investigator judgement is expected for legally marketed products ingested for other than the approved indication(s)

3. Participants who test positive to THC should be screen failed and can be considered for rescreening after a \>6-week washout period. Participants can only be rescreened once. Positive test results for all other substances shall be reviewed by the investigator and participants shall only be screen failed if the investigator believes the use of the substance may be clinically significant with regards to the participant's safe participation in this study or may confound this study's findings.

16. Severe depression, defined as a score of ≥30 on the Major Depression Inventory (MDI) questionnaire.

17. Severe anxiety, defined as score of \>15 on the General Anxiety Disorder-7 (GAD-7) questionnaire.

1. Severe psychiatric disorder that might be aggravated or exacerbated by dronabinol's potential to cause anxiety/nervousness, depersonalization, hallucination, etc.

2. Respiratory and neuromuscular diseases that could interfere with the results of the trial in the opinion of the investigator.

3. Cardiac dysfunction and/or its treatment that might augment dronabinol's potential to cause tachycardia or vasodilation.

4. Marked hepatic dysfunction as defined by elevated alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥3 × the upper limit of normal (ULN), that would reduce dronabinol metabolism.

i. One retest per participant is permitted at the discretion of the investigator; the participant may continue if BOTH repeat transaminase levels are within acceptable range (i.e., less than 3 × ULN).

e. Current or history of encephalopathy or cirrhosis Child-Pugh category B or C (see Appendix 8) since acetazolamide can increase blood ammonia levels precipitating a bout of hepatic encephalopathy.

f. Marked renal dysfunction that would reduce acetazolamide excretion, including eGFR \<60 mL/min/1.73 m2, as determined using the National Kidney Foundation calculator (https://www.kidney.org/professionals /kdoqi/gfr\_calculator) and instructions in Appendix 9.

g. Hypokalemia (low blood potassium), hyponatremia (low blood sodium), hyperchloremic acidosis, and/or adrenal insufficiency that might be aggravated or exacerbated by acetazolamide's activity as a carbonic anhydrase inhibitor.

19. Known CYP2C9 poor metabolizers (NB: this is based on medical history and does not need to be tested genetically).

20. Other ongoing condition(s) that the investigator considers may be clinically significant with regards to the participant's safe participation in this study or may confound this study's findings; any consideration should be discussed with the medical monitor or with the sponsor (such as known alcohol abuse).

21. Shift workers whose shift pattern has the potential to disrupt sleep patterns.

22. Participation in any other interventional studies involving investigational or marketed products within 30 days or 5.5 half-lives, whichever is longer, prior to screening.

What this study is about