What Is Solriamfetol?
Solriamfetol is an FDA-approved medication for treating insomnia. This drug is being studied for its potential to promote wakefulness and reduce excessive sleepiness across a range of conditions. Clinical trials are investigating solriamfetol for conditions such as obstructive sleep apnea, narcolepsy, and hypersomnia. Research also includes its use for excessive sleepiness, shift-work disorder, and excessive daytime sleepiness. Furthermore, studies are exploring solriamfetol for long COVID-19, binge-eating disorder, and major depressive disorder with excessive daytime sleepiness symptoms. Across all studies, solriamfetol has been investigated in 19 trials involving a total of 6,310 participants. The first trial began on 2020-10-26, and the latest is expected to conclude on 2026-03-20. It is typically administered as a tablet taken once daily.
Uses and Conditions Under Study
Solriamfetol is being investigated in clinical trials for its potential to address various conditions, primarily those involving excessive sleepiness or the need for wakefulness promotion.
- Sleep Disorders and Excessive Sleepiness: Several trials are focused on sleep-related conditions. This includes 3 trials for Obstructive Sleep Apnea, a condition where breathing repeatedly stops and starts during sleep. For Narcolepsy, a chronic neurological condition causing overwhelming daytime sleepiness, 2 trials are underway. Hypersomnia, characterized by excessive daytime sleepiness despite adequate nighttime sleep, is being studied in 2 trials. Additionally, solriamfetol is being explored for general Excessive Sleepiness in 3 trials and Excessive Daytime Sleepiness in 2 trials. Shift-work Disorder, which affects individuals working irregular hours, is the focus of 2 trials. One trial is also investigating its use in Major Depressive Disorder With Excessive Daytime Sleepiness Symptoms.
- Long COVID-19: The medication is also being studied for its effects on symptoms associated with long COVID-19. A total of 4 trials are investigating solriamfetol for Long COVID-19 and Long COVID, addressing persistent health problems that can occur weeks or months after the initial infection.
- Binge-Eating Disorder: Solriamfetol is being explored as a potential treatment for Binge-Eating Disorder, an eating disorder characterized by recurrent episodes of eating large quantities of food, in 2 trials.
These studies are sponsored by various organizations, including Axsome Therapeutics, Inc., which is involved in 9 trials, and academic institutions like Duke University and Johns Hopkins University.
Dosing
Solriamfetol is provided in tablet form and is generally taken once daily, typically upon awakening. This administration schedule helps to promote wakefulness throughout the day. Clinical trials have explored a range of strengths for the medication.
Strengths studied include:
- 37.5 mg
- 75 mg
- 150 mg
- 300 mg
For instance, in a trial investigating idiopathic hypersomnia, participants started with a dose of 75 mg. This dose was then progressively increased, as tolerated, up to 300 mg, allowing for individual adjustment to achieve optimal effect. Specific dosage forms like Solriamfetol 150mg and Solriamfetol 300mg have also been part of clinical investigations. The brand name for solriamfetol is Sunosi.
Side Effects
In a clinical trial involving patients taking Solriamfetol, the most commonly reported side effect was headache. 48.3% of patients taking Solriamfetol experienced headache, compared to 29.0% of patients taking a placebo.
Other common side effects reported more frequently in patients taking Solriamfetol compared to placebo included:
- Insomnia: 31.0% of patients on Solriamfetol experienced insomnia, compared to 16.1% on placebo.
- Gastrointestinal issues (such as nausea, vomiting, or diarrhea): 24.1% of patients on Solriamfetol, compared to 6.5% on placebo.
- Decreased appetite: 17.2% of patients on Solriamfetol, compared to 6.5% on placebo.
- Cardiovascular events: 17.2% of patients on Solriamfetol, compared to 3.2% on placebo.
- Neurological issues: 13.8% of patients on Solriamfetol, compared to 3.2% on placebo.
- Increased energy: 13.8% of patients on Solriamfetol, compared to 3.2% on placebo.
Clinical Trial Results
Excessive Sleepiness Related to Shift Work Disorder
A clinical trial (NCT04788953) investigated the effectiveness of Solriamfetol (Sunosi) for excessive sleepiness associated with shift work disorder. The study found that a significantly higher percentage of participants treated with Solriamfetol showed overall improvement compared to those on placebo. Specifically, 77.8% of participants taking Solriamfetol were rated as improved by clinicians, compared to 48.6% on placebo. Similarly, 78.9% of patients taking Solriamfetol reported improvement themselves, compared to 47.2% on placebo.
Solriamfetol also demonstrated improvements in objective and subjective measures of sleepiness and functional impairment:
- On the Epworth Sleepiness Scale, Solriamfetol reduced sleepiness scores by an average of 7.2 points, indicating a significant decrease in sleepiness, while placebo reduced scores by 2.4 points.
- Participants taking Solriamfetol experienced an increase in mean sleep latency (the time it takes to fall asleep) of 12.6 minutes, meaning they could stay awake longer, compared to an increase of 3.2 minutes for placebo.
- Overall work impairment, measured by the Work Productivity and Activity Impairment Questionnaire, decreased by 21.6 points for Solriamfetol users, indicating improved work function, compared to a 4.9-point decrease for placebo.
- The Sheehan Disability Scale, which measures functional impairment, showed a reduction of 6.8 points with Solriamfetol, compared to 3.1 points with placebo, suggesting improved daily functioning.
Cognitive Health in Apnea Participants
In a randomized, placebo-controlled study (NCT04789174) evaluating Solriamfetol's effect on cognitive health in apnea patients, participants treated with Solriamfetol showed greater improvement in cognitive function. The average change from baseline in DSST RBANS scores was an increase of 6.49 points for Solriamfetol, indicating improved cognitive performance, compared to a 4.75-point increase for placebo.
Attention Deficit Hyperactivity Disorder (ADHD) in Adults
A controlled study (NCT04839562) examined Solriamfetol for adults with ADHD. The study found that 13 participants taking Solriamfetol met the a priori definition of clinical improvement, compared to 2 participants on placebo.
Key findings regarding ADHD symptoms and executive function included:
- The Adult ADHD Investigator Symptom Rating Scale (AISRS) total score decreased by an average of 7.6 points for those on Solriamfetol, indicating reduced ADHD symptoms, compared to a 2.1-point decrease for placebo.
- For the Brief Rating Inventory of Executive Function-Adult Version (BRIEF-A) Global Executive Composite Index, 20 participants on Solriamfetol showed at least a 0.5 standard deviation improvement, compared to 10 participants on placebo.
- Regarding the Plan/Organize subscale of the BRIEF-A, 19 participants on Solriamfetol showed at least a 0.5 standard deviation improvement, compared to 11 participants on placebo.
Currently Recruiting Trials
Several clinical trials are currently recruiting participants to further explore the potential benefits of Solriamfetol for various conditions. These studies aim to gather more information on how Solriamfetol might help patients manage their symptoms and improve their quality of life.
- The CLARITY study, NCT07484217, is a Phase 3 trial sponsored by Axsome Therapeutics, Inc. It is designed to assess Solriamfetol 150mg in patients with Major Depressive Disorder who also experience excessive daytime sleepiness. This double-blind, placebo-controlled study plans to enroll 508 participants.
- Another Phase 3 study, NCT06878976, sponsored by Axsome Therapeutics, Inc., is an open-label safety study investigating Solriamfetol for Binge-Eating Disorder. This trial aims to enroll 300 adults to evaluate the long-term safety and efficacy of the treatment.
- The SUSTAIN trial, NCT06568367, also a Phase 3 study from Axsome Therapeutics, Inc., is examining Solriamfetol in adults with excessive sleepiness associated with Shift-work Disorder. This randomized, double-blind trial is testing Solriamfetol at dosages of 150mg and 300mg, with an enrollment target of 520 participants.
- Johns Hopkins University is sponsoring a Phase 2 trial, NCT06170970, focusing on Solriamfetol for Multiple Sclerosis Fatigue. This study is exploring different sequences of Solriamfetol and placebo, with a target enrollment of 46 participants.
- The ENGAGE study, NCT06413433, is a Phase 3, randomized, double-blind, placebo-controlled trial sponsored by Axsome Therapeutics, Inc. It is assessing the efficacy and safety of Solriamfetol 150 mg and 300 mg for the treatment of Binge-Eating Disorder in adults, aiming to enroll 450 participants.
- Finally, the NCT06413420 study is the SUNOSI (Solriamfetol) Pregnancy Registry, a prospective, observational study sponsored by Axsome Therapeutics, Inc. This registry is evaluating the safety of Solriamfetol exposure during pregnancy in women diagnosed with narcolepsy or obstructive sleep apnea, with a substantial enrollment target of 1731 participants.
Where to Participate
Clinical trials for Solriamfetol have a broad geographic reach, with study sites located across 24 states in 76 cities. There are currently 4 active sites accepting new participants. The top cities with multiple study locations include:
- Miami, Florida (8 sites)
- Cincinnati, Ohio (5 sites)
- Austin, Texas (4 sites)
- Boston, Massachusetts (3 sites)
- Jacksonville, Florida (3 sites)
- San Antonio, Texas (3 sites)
- Hialeah, Florida (3 sites)
- Portland, Oregon (3 sites)
- Cherry Hill, New Jersey (3 sites)
- Long Beach, California (3 sites)
Eligibility for these trials generally includes adults aged 18-65 years, regardless of gender. Participants are typically not healthy volunteers, meaning they have a specific medical condition being studied. Some studies may also include children, depending on the specific trial design.
Development Timeline
The journey of Solriamfetol in clinical development began on October 26, 2020, with the latest trial projected to conclude in March 2026. Since its inception, a total of 19 clinical trials have been initiated, enrolling over 6,310 participants across various phases. Axsome Therapeutics, Inc. has been a primary driver, sponsoring 9 of these studies, alongside contributions from institutions like Johns Hopkins University and Duke University.
Initially, Solriamfetol was explored for conditions such as IBS-C and hyperphosphatemia. However, its development pipeline quickly expanded, focusing on disorders related to sleep and neurological function. The drug's journey progressed through Phase 1, Phase 2, and Phase 3 trials, with 7 studies reaching the advanced Phase 3 stage and 5 in Phase 4. The range of conditions under investigation has broadened significantly to include narcolepsy, obstructive sleep apnea, shift-work disorder, and excessive daytime sleepiness. More recently, the scope has expanded to include binge-eating disorder, major depressive disorder with excessive daytime sleepiness symptoms, and multiple sclerosis fatigue, demonstrating a continuous effort to explore Solriamfetol's potential across a diverse set of patient needs.