Adults 18 to 64, any sex, with Excessive Sleepiness or Shift-work Disorder. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Change in Mean Sleep LatencyPrimary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Sleep latency was assessed with a Maintenance Wakefulness Test (MWT) at Visit 2 (Baseline) and again at Visit 5 (End-of-Treatment). The MWT started \~2 hours after participant's usual wake time and consisted of four 40-minute trials (2, 4, 6, and 8 hours after usual wake time). Participants were fitted with polysomnography (PSG) and instructed to stay awake. Each trial was monitored and the trial was ended after PSG-sleep occurred or after 40 minutes if no sleep occurred. Sleep latency (in minutes) was calculated as the time between trial start time and sleep onset time. Change in mean sleep l
Group
Value
95% CI
Solriamfetol (Sunosi)
12.6
10.0 – 15.2
Control
3.2
0.6 – 5.8
Change in Karolinska Sleepiness Scale ScoreSecondary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Subjective sleepiness was assessed with a Karolinska Sleepiness Scale (KSS, Åkerstedt \& Gillberg, 1990). The KSS was administered to the participant \~5 minutes before the start of each four MWT trial at Visit 5 (Baseline) and again at Visit 5 (End-of-Treatment). The KSS scores range from 1 (very alert) to 9 (very sleepy), with higher scores indicating higher levels of sleepiness. Change in the mean KSS score (i.e., averaged score across the four trials) from Visit 2 to Visit 5 was calculated for each participant.
Group
Value
95% CI
Solriamfetol (Sunosi)
-1.7
-2.0 – -1.3
Control
-0.5
-0.8 – -0.1
Change in Clinician's Global Impression of Change ScoreSecondary· Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Overall change in participant's clinical condition was assessed with a Clinician's Global Impression of Change scale (CGI-Change, Guy, 1976). The CGI-change was conducted at Visit 5 (End-of-Treatment) by a study doctor who rated the participant. The scores range from 1 (very much improved) to 7 (very much worse), with lower scores indicating improved condition. Data were dichotomized such that scores 1-3 (very much improved, much improved, minimally improved) were considered to indicate improvement and scores 4-7 (no change, minimally worse, much worse, very much worse) were considered to indi
Group
Value
95% CI
Solriamfetol (Sunosi)
77.8
Control
48.6
Change in Patient's Global Impression of Change ScoreSecondary· Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Participant's overall perception of change in their condition (i.e., excessive sleepiness) was assessed with a Patient's Global Impression of Change scale (PGI-Change, Guy, 1976). The PGI-C was administered to the participant at Visit 5 (End-of-Treatment). The scores ranged from 1 (no change or worse) to 7 (a great deal better), with higher scores indicating improved condition. Data were dichotomized such that scores 1-2 (no change or worse, hardly any change) were considered to indicate no improvement, and scores 3-7 (a little better, somewhat better, moderately better, better, a great deal b
Group
Value
95% CI
Solriamfetol (Sunosi)
78.9
Control
47.2
Change in Overall Work Impairment Score From the Work Productivity and Activity Impairment QuestionnaireSecondary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Work impairment was assessed with a Work Productivity and Activity Impairment-Specific Health Problem questionnaire (WPAI-SHP, Reilly et al., 1993; Emsellem et al., 2020), with excessive sleepiness as the specific health problem. The WPAI-SHP questionnaire was administered to the participant at Visit 2 (Baseline) and again at Visit 5 (End-of-Treatment). Overall work impairment score, which ranges from 0 to 100 with higher score indicating more impairment, was calculated from the WPAI-SHP subscales according to the WPAI scoring manual by Dr. Reilly. Change in the overall work impairment score f
Group
Value
95% CI
Solriamfetol (Sunosi)
-21.6
-31.5 – -11.7
Control
-4.9
-15.0 – 5.3
Change in Functional Outcomes of Sleep Questionnaire ScoreSecondary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
Subjective global functioning was assessed with the short version of the Functional Outcomes of Sleep Questionnaire (FOSQ-10; Chasens et al., 2009). The FOSQ-10 was administered to the participant at Visit 2 (Baseline) and again at Visit 5 (End-of-Treatment). The FOSQ-10 consists of ten subscales with each subscale ranging from 1 (extreme difficulty) to 4 (no difficulty). The FOSQ-10 total score, which was calculated as the mean-weighted item score computed from the ten subscales, ranges from 5 to 20 with higher scores indicating less functional impairment. Change in FOSQ-10 total score from V
Group
Value
95% CI
Solriamfetol (Sunosi)
2.0
0.9 – 3.0
Control
1.6
0.5 – 2.7
Change in Sheehan Disability Scale ScoreSecondary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End-of-Treatment Visit after 4 weeks on solriamfetol or placebo)
The impact of excessive sleepiness on subjective global functioning was assessed with a Sheehan Disability Scale (SDS; Sheehan \& Sheehan, 2008). The questionnaire was administered to the participants at Visit 2 (Baseline) and again at Visit 5 (End-of-Treatment). The SDS consists of five subscales, with the scores for the three subscales (work, social, and family life) that are used for calculating the total score ranging from 0 (not at all impacted) to 10 (extremely impacted). The SDS total score, which was calculated as the sum of the three subscale scores, ranges from 0 to 30 with higher sc
Group
Value
95% CI
Solriamfetol (Sunosi)
-6.8
-9.3 – -4.4
Control
-3.1
-5.6 – -0.6
Change in Total Sleep TimeSecondary· Baseline Segment (2 weeks) and Treatment Segment (4 weeks)
Total Sleep Time (TST) was assessed with actigraphy. Participants wore a wrist activity monitor throughout the study (i.e., 2 weeks of baseline and 4 weeks of treatment). The actigraphy data from the main sleep periods were manually scored in 30-second epochs, and TST was calculated in minutes for each study day. Change in TST from baseline to treatment was calculated for each participant.
Group
Value
95% CI
Solriamfetol (Sunosi)
-3.6
-13.5 – 6.3
Control
-7.2
-17.3 – 2.9
Change in Sleep Fragmentation IndexSecondary· Baseline Segment (2 Weeks) and Treatment Segment (4 Weeks)
Sleep disturbances were assessed with actigraphy-derived fragmentation index. Participants wore a wrist activity monitor throughout the study (i.e., 2 weeks of baseline and 4 weeks of treatment). The actigraphy data from the main sleep periods were manually scored in 30-second epochs in the MotioWare software (CamNtech, Cambridge, UK). MotionWare defines the fragmentation index as the sum of the percentages of mobile time and immobile bouts immobile bouts below or equal to 1 minute during the sleep period, which is a unitless measure. Change in fragmentation index from baseline to treatment wa
Group
Value
95% CI
Solriamfetol (Sunosi)
0.5
-0.5 – 1.5
Control
0.9
-0.1 – 1.9
Change in Epworth Sleepiness Scale ScoreSecondary· Study Visit 2 (i.e., Baseline Visit) and Study Visit 5 (i.e., End of Treatment Visit after 4 weeks on solriamfetol or placebo)
Subjective sleepiness was assessed with a modified Epworth Sleepiness Scale (ESS, Johns, 1990, 1997). The ESS was administered to the participant at Visit 2 (Baseline) and again at Visit 5 (End-of-Treatment). The ESS consists of eight subscales with each subscale ranging from 0 (never doze) to 3 (high change to doze off). The ESS total score, which was calculated as the sum of the eight subscalescores, ranges from 0 (normal levels of sleepiness) to 24 (severe excessive sleepiness) with higher scores indcating higher levels of sleepiness. Change in the ESS total score from Visit 2 to Visit 5 wa
Group
Value
95% CI
Solriamfetol (Sunosi)
-7.2
-8.8 – -5.5
Control
-2.4
-4.1 – -0.8
Adverse events — posted to ClinicalTrials.gov
Time frame: Adverse events data for each participant was collected for approximately 4 weeks. This spanned the time period between Visit 3 (solriamfetol/placebo dispensed to the participant) and Visit 5 (last solriamfetol/placebo dose)..
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
In this research study the investigators want to learn more about whether the medication Solriamfetol improves daytime sleepiness in workers who start work at very early times (between 3 and 6am).
Publications & conference data
1 peer-reviewed publication reference this trial (live from Europe PMC):
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Charles A. Czeisler, PhD, MD
Last refreshed: 24 September 2025
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04788953.