Solriamfetol Reduces Excessive Sleepiness in Patients With Narcolepsy and OSA

Solriamfetol Improves Work Productivity

Helene Emsellem, MD, Medical Director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland, and colleagues analyzed data from the same phase III study to examine solriamfetol’s effects on health-related quality of life and work productivity. These outcomes had been measured using the Functional Outcomes of Sleep Questionnaire, short version (FOSQ-10); the Work Productivity and Activity Impairment questionnaire for Specific Health Problem, which measures absenteeism, presenteeism (ie, working while impaired), and activity impairment outside of work; and the 36-Item Short Form Health Survey version 2 (the SF-36 v2), which includes physical and mental components. Dr. Emsellem and colleagues calculated the least-squares mean change in these measures from baseline to Week 12.

At baseline, mean FOSQ-10 total score was 12.2 among controls, 11.4 in the 75-mg group, 11.7 in the 150-mg group, and 11.4 in the 300-mg group. A normal value is approximately 18. At Week 12, FOSQ-10 score improved by 3.01 points in the 300-mg group, compared with 1.56 among controls. The difference between these groups was statistically significant. FOSQ-10 score improved by 2.39 in the 75-mg group and by 2.57 in the 150-mg group, but these results were not statistically significant.

At Week 12, the 150-mg and 300-mg doses of solriamfetol significantly reduced activity impairment outside of work, compared with placebo. In addition, the 150-mg dose significantly reduced presenteeism and a composite of absenteeism and presenteeism, compared with placebo. Solriamfetol had little effect on absenteeism, perhaps because absenteeism was uncommon at baseline, said Dr. Emsellem.

In addition, the 300-mg dose of solriamfetol significantly increased by 3.29 points the physical component summary score of the SF-36 v2, compared with placebo, which yielded a 1.06-point increase. The other doses did not significantly improve the physical component summary score. Solriamfetol did not significantly improve the mental component summary score.

Data Suggest Long-Term Efficacy

Pharmacologic treatment for narcolepsy often lasts for a long period of time, but the treatment periods in many clinical trials are comparatively short. Atul Malhotra, MD, Professor of Medicine at the University of California, San Diego, and colleagues conducted a study to examine the long-term safety and efficacy of solriamfetol.

Eligible participants had narcolepsy or OSA and had previously completed six- or 12-week trials of solriamfetol. Patients in Group A were enrolled into the long-term study immediately after having completed an earlier study, and patients in Group B were enrolled later after their completion of the earlier study.

Participants received open-label solriamfetol during a two-week titration phase. The subsequent maintenance phase lasted for 38 weeks for Group A and 50 weeks for Group B. After about six months of treatment, investigators randomized blinded patients to placebo or their assigned dose of solriamfetol for two weeks. After this randomized-withdrawal phase, all participants received solriamfetol.