Solriamfetol for the treatment of daytime sleepiness in obstructive sleep apnea

Solriamfetol improves chronic sleep fragmentation-induced increases in sleep propensity and ameliorates explicit memory in male mice

Obstructive sleep apnea (OSA) is a highly prevalent condition characterized by episodes of partial or complete breath cessation during sleep that induces sleep fragmentation (SF). One of the frequent manifestations of OSA is the presence of excessive daytime sleepiness (EDS) associated with cognitive deficits. Solriamfetol (SOL) and modafinil (MOD) are wake-promoting agents commonly prescribed to improve wakefulness in OSA patients with EDS. This study aimed to assess the effects of SOL and MOD in a murine model of OSA characterized by periodic SF. Male C57Bl/6J mice were exposed to either control sleep (SC) or SF (mimicking OSA) during the light period (06:00 h to 18:00 h) for 4 weeks, which consistently induces sustained excessive sleepiness during the dark phase. Both groups were then randomly assigned to receive once-daily intraperitoneal injections of SOL (200 mg/kg), MOD (200 mg/kg), or vehicle for 1 week while continuing exposures to SF or SC. Sleep/wake activity and sleep propensity were assessed during the dark phase. Novel Object Recognition test, Elevated-Plus Maze Test, and Forced Swim Test were performed before and after treatment. SOL or MOD decreased sleep propensity in SF, but only SOL induced improvements in explicit memory, while MOD exhibited increased anxiety behaviors. Chronic SF, a major hallmark of OSA, induces EDS in young adult mice that is mitigated by both SOL and MOD. SOL, but not MOD, significantly improves SF-induced cognitive deficits. Increased anxiety behaviors are apparent in MOD-treated mice. Further studies aiming to elucidate the beneficial cognitive effects of SOL are warranted.

Indirect treatment comparison of solriamfetol, modafinil, and armodafinil for excessive daytime sleepiness in obstructive sleep apnea

STUDY OBJECTIVES

Excessive daytime sleepiness associated with obstructive sleep apnea affects 9%-22% of continuous positive airway pressure-treated patients. An indirect treatment comparison meta-analysis was performed to compare efficacy and safety of medications (solriamfetol, modafinil, and armodafinil) approved to treat excessive daytime sleepiness associated with obstructive sleep apnea.

METHODS

Efficacy and safety measures assessed in this indirect treatment comparison included Epworth Sleepiness Scale (ESS), 20-minute Maintenance of Wakefulness Test (MWT20), Clinical Global Impression of Change (CGI-C), Functional Outcomes of Sleep Questionnaire (FOSQ), and incidence of treatment-emergent adverse events (any, serious, or leading to discontinuation).

RESULTS

A systematic literature review identified 6 parallel-arm, placebo-controlled randomized controlled trials that randomized 1,714 total participants to placebo, solriamfetol, modafinil, or armodafinil. In this indirect treatment comparison, all comparators were associated with greater improvements than placebo on the ESS, MWT20, and CGI-C after 4, 8, and 12 weeks of treatment. Relative to comparators and placebo at 12 weeks, solriamfetol at 150 mg or 300 mg had the highest probabilities of improvement in the ESS, MWT20, and CGI-C. Modafinil (200 or 400 mg) and solriamfetol (150 or 300 mg) were associated with greater improvement on the FOSQ than placebo at 12 weeks. Less than 2% of patients using placebo or comparators experienced serious or discontinuation-related treatment-emergent adverse events.

CONCLUSIONS

The results of this indirect treatment comparison show 12 weeks of treatment with solriamfetol, modafinil, and armodafinil resulted in varying levels of improvement on the ESS, MWT20, and CGI-C and similar safety risks in participants with excessive daytime sleepiness associated with obstructive sleep apnea.

CITATION

Ronnebaum S, Bron M, Patel D, et al. Indirect treatment comparison of solriamfetol, modafinil, and armodafinil for excessive daytime sleepiness in obstructive sleep apnea. J Clin Sleep Med. 2021;17(12):2543-2555.

Diagnostik und Therapie der residualen Tagesschläfrigkeit bei Patienten mit therapierter obstruktiver Schlafapnoe

Die residuale Tagesschläfrigkeit tritt bei 12–65 % der Schlafapnoe-Patienten unter eingeleiteter Positivdrucktherapie („positive airway pressure“) auf. Eine häufige Ursache ist die geringe PAP-Nutzungszeit. Mögliche weitere Gründe sind ein hoher Rest-Apnoe-Hypopnoe-Index und eine vorhandene Komorbidität. Prädiktoren sind ein initial hoher Epworth-Schläfrigkeitsscore, jüngeres Alter und die erst kurze PAP-Nutzung. Gesichert wird die Restschläfrigkeit mittels objektiver Testverfahren (z. B. multipler Wachbleibetest oder Oxford Sleep Resistance Test [Osler-Test]). Eine der wesentlichen Ursachen für die residuale Schläfrigkeit nach Ausschluss konkurrierender Auslöser ist die stattgehabte intermittierende nächtliche Hypoxämie, die zu nervalen Zellschädigungen, zu hormonellen und genetischen Veränderungen und zu Änderungen des Mikrobioms führen kann.

Die klinischen Beschwerden werden bestimmt durch eine ausgeprägte Tagesschläfrigkeit, depressive Verstimmung und eine Minderung der Lebensqualität.

Nach Ausschluss möglicher therapiebedingter Ursachen kann die residuale Tagesschläfrigkeit medikamentös mit u. a. Modafinil, Armodafinil, Pitolisant oder Solriamfetol behandelt werden. Die genannten Arzneimittel haben unterschiedliche Wirkmechanismen. Die Studien und die Effekte der Substanzen auf die Tagesschläfrigkeit, die Lebensqualität und die Leistungsfähigkeit der Betroffenen werden vorgestellt. Das Nebenwirkungsprofil der Wirkstoffe ist ähnlich. Für die Indikation residuale Schläfrigkeit einer therapierten obstruktiven Schlafapnoe ist in Europa derzeit nur Solriamfetol zugelassen.

Ein vom Autorenteam entworfener Behandlungspfad für Patienten mit therapierter obstruktiver Schlafapnoe mit residualer Tagesschläfrigkeit, von der Erstvorstellung nach Therapiebeginn über die Therapieoptimierung bis hin zu einer medikamentösen Behandlung, wird vorgestellt.

Synthetic Approaches to the New Drugs Approved during 2019

New drugs introduced to the market are privileged structures having affinities for biological targets implicated in human diseases and conditions. These new chemical entities (NCEs), particularly small molecules and antibody-drug conjugates, provide insight into molecular recognition and simultaneously function as leads for the design of future medicines. This review is part of a continuing series presenting the most likely process-scale synthetic approaches to 40 NCEs approved for the first time anywhere in the world in 2019.

Profile of Solriamfetol in the Management of Excessive Daytime Sleepiness Associated with Narcolepsy or Obstructive Sleep Apnea: Focus on Patient Selection and Perspectives

Excessive sleepiness (ES) is a symptom of obstructive sleep apnea (OSA) and narcolepsy that has severe consequences. Wake-promoting drugs and stimulants are utilized as accessory treatment in OSA to reduce propensity to sleep but they do not improve sleep-disordered breathing. Solriamfetol is a first-line therapeutic agent to combat sleepiness in OSA and narcolepsy patients that is approved both by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). For excessively sleepy adult patients with OSA despite primary treatment or narcolepsy patients without cataplexy, solriamfetol may be used as initial therapy or as replacement therapy in patients who fail treatment or experience unacceptable side effects with modafinil, armodafinil, pitolisant, or stimulants. It can also be used as add-on therapy in OSA or narcolepsy patients when ES is only partially controlled with modafinil, armodafinil, pitolisant, sodium oxybate, or stimulants. Solriamfetol is a phenylalanine derivative whose wake-promoting action may be mediated through its selective dopamine and norepinephrine reuptake inhibition. This paper reviews the profile of solriamfetol in treating ES associated with OSA or narcolepsy and discusses patient selection and clinical perspectives. Mechanism of action, pharmacology, pharmacokinetics, clinical efficacy, and tolerability of solriamfetol are described. The Treatment of OSA and Narcolepsy Excessive Sleepiness (TONES) solriamfetol trials demonstrated the efficacy of solriamfetol in reducing propensity to sleep and maintaining wakefulness, with significant improvements in mean maintenance of wakefulness test (MWT) sleep latencies and significant reduction in Epworth Sleepiness Scale (ESS) scores compared to placebo. With solriamfetol, significantly higher percentages of patients showed improvement in patient's and clinician's global impression of change.

Update on Persistent Excessive Daytime Sleepiness in OSA

OSA is a highly prevalent sleep disorder, and subjective excessive daytime sleepiness (EDS) is the cardinal symptom for which many individuals seek medical advice. Positive airway pressure (PAP) devices, first-line treatment for OSA, eliminates EDS in most patients. However, a subset of patients suffers from persistent EDS despite adherence to therapy. Multiple conditions, some reversible, could account for the residual sleepiness and need to be explored, requiring detailed history, review of PAP data from the smart card, and sometimes additional testing. When all known causes of EDS are excluded, in adequately treated subjects, the purported mechanisms could relate to long-term exposure to the OSA-related sleep fragmentation, sleep deprivation, and hypoxic injury to the arousal system, shifts in melatonin secretion, or altered microbiome. Independent of the mechanism, in well-treated OSA, pharmacological therapy with approved drugs can be considered. Modafinil is commonly prescribed to combat residual EDS, but more recently two drugs, solriamfetol, a dual dopamine-norepinephrine reuptake inhibitor, and pitolisant, a histamine H3 receptor inverse agonist, were approved for EDS. Solriamfetol has undergone randomized controlled trials for treatment of EDS associated with both OSA and narcolepsy, exhibiting robust efficacy. Solriamfetol is renally excreted, with no known drug interactions. Pitolisant, which is nonscheduled, has undergone multiple RCTs in narcolepsy, showing improvement in subjective and objective EDS and one OSA trial showing improvement in subjective EDS.