Apnea/Hypopnea Index in OSA Improves With Dronabinol

Adults with obstructive sleep apnea (OSA) treated with dronabinol may experience a lower apnea/hypopnea index (AHI), improvement in subjective sleepiness, and higher overall treatment satisfaction compared with those treated with placebo, according to a study published in Sleep.

PACE (Pharmacotherapy of Apnea by Cannabimimetic Enhancement; ClinicalTrials.gov identifier: NCT01755091) was a phase 2, prospective multisite fully blinded parallel group randomized placebo-controlled clinical trial. A total of 73 individuals aged 21 to 65 years with moderate or severe OSA were recruited and randomly assigned to receive placebo (n=25), 2.5 mg/d dronabinol (n=21), or 10 mg/d dronabinol (n=27) 1 hour before bedtime for up to 42 days. 

The primary end point of the study was to determine whether dose-dependent dronabinol could reduce the severity of OSA and daytime sleepiness in individuals with moderate or severe OSA.

The investigators found that individuals who received 10 mg/d of dronabinol demonstrated a higher overall satisfaction with pharmacotreatment (P =.04). AHI was reduced in participants who received dose-dependent dronabinol by 10.7±4.4 events/d (P =.02) with 2.5 mg/d, and 12.9±4.3 events/d at 10 mg/d (P =.003) compared with placebo. 

Finally, the Epworth Sleepiness Scale (ESS) score was reduced by –3.8±0.8 points from baseline in participants who received 10 mg/d dronabinol (P <.0001) and by –2.3±1.2 points when scores were compared with scores in those treated with placebo (P =.05). Parameters that did not change from baseline in all treatment groups were maintenance of wakefulness test, gross sleep architecture, and overnight oxygen parameters.

Adverse events were reported in 88% of participants. Sleepiness/drowsiness (n=25), headache (n=24), nausea/vomiting (n=23), and dizziness/lightheadedness (n=12) were the most commonly reported adverse events, and the frequency of adverse events did not differ between treatment groups (P >.1). In addition, no associated weight gain was found in individuals treated with dronabinol during the course of the study.

Study limitations included uneven randomization, overall small sample size, and significant differences in participant ages. Cessation of other noninvasive treatments as a requirement for study participation may be a confounding variable for the results.

Researchers concluded that overall, dronabinol is a safe and effective pharmacotherapy treatment for individuals with moderate or severe OSA that can reduce AHI in a dose-dependent manner and improve subjective sleepiness when compared with placebo. Clinicians may consider the use of dronabinol as adjunctive treatment in certain patients with OSA.

Reference

Carley DW, Prasad B, Reid KJ, et al. Pharmacotherapy of apnea by cannabimimetic enhancement, the PACE clinical trial: effects of dronabinol in obstructive sleep apnea [published online November 7, 2017]. Sleep. doi:10.1093/sleep/zsx184