Solriamfetol, a dopamine and norepinephrine reuptake inhibitor approved by the United States Food and Drug Administration, offers short-term improvements in functional status, health-related quality of life (HRQoL), and work productivity in people with narcolepsy, according to study results published in Sleep Medicine.
Narcolepsy has been linked to several significant effects on quality of life in people living with this disease. For example, the rate of job loss ranges from 37% to 52%, which is attributed to the deleterious effects on job performance as a result of the symptoms of narcolepsy. There is no cure for narcolepsy; treatments aim to ameliorate symptoms. Solriamfetol is approved for the use of improving wakefulness in adult patients.
Because few studies have evaluated the efficacy of treatment on functioning, QoL, and work productivity, researchers conducted a 12-week, randomized, double-blind, placebo-controlled, multicenter, 4-arm, parallel-group study to evaluate the safety and efficacy of solriamfetol for the treatment of excessive daytime sleepiness (EDS) in adult patients with narcolepsy. The primary outcome measures were changes in functional status related to sleepiness, HRQoL, and work productivity.
In this phase 3 study, adults with narcolepsy were randomly assigned to receive either 75 mg solriamfetol (n=59), 150 mg solriamfetol (n=59), 300 mg solriamfetol (n=59), or placebo (n=59). Treatment was administered once per day in the morning for a total of 12 weeks. Investigators assessed changes in the Functional Outcomes of Sleep Questionnaire short version (FOSQ-10), 36-Item Short Form Health Survey version 2 (SF-36v2), and Work Productivity and Activity Impairment questionnaire for Specific Health Problem (WPAI:SHP) between baseline and 12-week follow-up.
At 12 weeks, treatment with 300 mg solriamfetol was associated with the greatest change in FOSQ-10 total score relative to placebo (least squares mean change, 3.0 vs 1.6, respectively; P =.01); lower doses of solriamfetol were associated with improvements as well, but to a lesser degree. There was a significant least squares mean change in the physical component summary scores on the SF-36v2 with 300 mg solriamfetol compared with placebo (3.3 vs 1.1, respectively; P =.05). Similar to FOSQ-10 scores, lower doses of solriamfetol were linked to improvements as well, but to a lesser degree. Stepwise increases on the SF-36v2 were observed with each increase in solriamfetol dose.
In terms of changes on the WPAI:SHP, most scores (percent impairment while working, percent overall work impairment, and percent activity impairment) improved across all treatment groups in a stepwise manner with increases in solriamfetol doses relative to placebo.
Treatment-emergent adverse events were reported in 68.4% of patients who received solriamfetol; the most common were headache, nausea, decreased appetite, nasopharyngitis, dry mouth, and anxiety.
Study limitations include the relatively short follow-up duration and the lack of power to detect differences in the HRQoL, functional status, and work productivity measures.
The findings from this study could have several significant implications, considering “narcolepsy imparts a substantial economic burden to patients, families, and insurance providers, with high healthcare service utilization and healthcare dollars spent.”
Disclosure: This clinical trial was supported by Jazz Pharmaceuticals. Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Emsellem HA, Thorpy MJ, Lammers GJ, et al. Measures of functional outcomes, work productivity, and quality of life from a randomized, phase 3 study of solriamfetol in participants with narcolepsy [published online December 4, 2019]. Sleep Med. doi:10.1016/j.sleep.2019.11.1250