Study Finds Solriamfetol Improves Alertness in Early Morning Shift Workers

Senior author Charles A. Czeisler, PhD, MD, noted that this is the first clinical trial to specifically target early morning shift workers, who often face severe fatigue as their work begins while most people are still asleep.

Around 25% of workers operate outside the standard 9 to 5 schedule, with many starting as early as 3 a.m. These workers may not identify as shift workers, yet they are at a high risk for shift work disorder, which manifests as disrupted sleep patterns and persistent daytime sleepiness. First author Kirsi-Marja Zitting, PhD, explained the challenges faced by these workers, stating that their brains are biologically programmed to sleep during early morning hours, making alertness particularly difficult.

Shift work disorder poses significant health and safety risks, including reduced cognitive function, lower productivity, and an increased likelihood of accidents and workplace injuries. While medications like modafinil promote wakefulness, they have primarily been studied in overnight workers and can disrupt sleep later in the day. In contrast, solriamfetol, already approved for excessive sleepiness related to obstructive sleep apnea and narcolepsy, shows promise for supporting alertness without significantly hindering later sleep.

In the study, 78 early morning shift workers diagnosed with shift work disorder were randomly assigned to receive either solriamfetol or a placebo over a four-week period. Results indicated that those taking solriamfetol experienced notable improvements in alertness during work hours. Participants reported feeling less sleepy and were able to stay awake longer, enhancing their overall functioning and performance.

Czeisler remarked on the significance of these findings, stating that improved wakefulness during a full shift carries substantial implications for worker performance, safety, and quality of life. He acknowledged the critical role of shift workers and highlighted that more could be done to support them.

Despite these promising results, the researchers called for further studies to explore the long-term effects of solriamfetol, noting the limited duration of this trial and its focus on otherwise healthy adults. They are currently enrolling participants for a follow-up clinical trial to assess solriamfetol's effects in overnight shift workers, which may help in seeking broader approval for treating shift work disorder.

The research team included additional authors from Mass General Brigham and was funded by Jazz Pharmaceuticals, Axsome Therapeutics, and the Brigham and Women's Hospital Center for Clinical Investigation.