Pitolisant for Residual Excessive Daytime Sleepiness in OSA Patients Adhering to CPAP: A Randomized Trial

Chest. 2021 Apr;159(4):1598-1609. doi: 10.1016/j.chest.2020.09.281. Epub 2020 Oct 26.


Background: Excessive daytime sleepiness (EDS) in individuals with OSA syndrome persisting despite good adherence to CPAP is a disabling condition. Pitolisant is a selective histamine H3-receptor antagonist with wake-promoting effects.

Research question: Is pitolisant effective and safe for reducing daytime sleepiness in individuals with moderate to severe OSA adhering to CPAP treatment but experiencing residual EDS?

Study design and methods: In a multicenter, double-blind, randomized (3:1), placebo-controlled, parallel-design trial, pitolisant was titrated individually at up to 20 mg/day and taken over 12 weeks. The primary end point was change in the Epworth Sleepiness Scale (ESS) score in the intention-to-treat population. Key secondary end points were maintenance of wakefulness assessed by the Oxford Sleep Resistance Test, Clinical Global Impressions scale of severity, the patient's global opinion, EuroQoL quality-of-life questionnaire score, Pichot fatigue questionnaire score, and safety.

Results: Two hundred forty-four OSA participants (82.8% men; mean age, 53.1 years; mean Apnea Hypopnea Index with CPAP, 4.2/h; baseline ESS score, 14.7) were randomized to pitolisant (n = 183) or placebo (n = 61). ESS significantly decreased with pitolisant compared with placebo (-2.6; 95% CI, -3.9 to -1.4; P < .001), and the rate of responders to therapy (ESS ≤ 10 or change in ESS ≥ 3) was significantly higher with pitolisant (71.0% vs 54.1%; P = .013). Adverse event occurrence (mainly headache and insomnia) was higher in the pitolisant group compared with the placebo group (47.0% and 32.8%, respectively; P = .03). No cardiovascular or other significant safety concerns were reported.

Interpretation: Pitolisant used as adjunct to CPAP therapy for OSA with residual sleepiness despite good CPAP adherence significantly reduced subjective and objective sleepiness and improved participant-reported outcomes and physician-reported disease severity.

Trial registry: ClinicalTrials.gov; No.: NCT01071876; URL: www.clinicaltrials.gov; EudraCT N°: 2009-017248-14; URL: eudract.ema.europa.eu.

Keywords: CPAP; OSA; pitolisant; residual excessive daytime sleepiness.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Continuous Positive Airway Pressure
  • Disorders of Excessive Somnolence / drug therapy*
  • Disorders of Excessive Somnolence / etiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Piperidines / therapeutic use*
  • Quality of Life
  • Receptors, Histamine H3 / therapeutic use*
  • Sleep Apnea, Obstructive / complications*
  • Sleep Apnea, Obstructive / therapy
  • Surveys and Questionnaires


  • Piperidines
  • Receptors, Histamine H3
  • pitolisant

Associated data

  • ClinicalTrials.gov/NCT01071876