New Drug Reduces ADHD Symptoms by 45%

For millions of adults with attention deficit hyperactivity disorder (ADHD), finding an effective treatment can be a challenge – especially for those who don’t respond well to traditional stimulant medications. Now, Axsome Therapeutics’ solriamfetol has shown promise in a Phase 3 clinical trial. According to a press release published by the company it demonstrated a 45% reduction in ADHD symptoms compared to baseline.

Challenges in ADHD treatment

ADHD is a chronic condition characterized by persistent patterns of inattention, hyperactivity and impulsivity that significantly impacts daily life. In the United States, ADHD affects ~15.5 million adults, with many individuals continuing to experience symptoms into adulthood.

“ADHD substantially impairs social, academic and occupational functioning, while negatively impacting patient quality of life and increasing the risk of morbidity and mortality,” said Dr. Gregory Mattingly, president of the American Professional Society for ADHD and Related Disorders.

Stimulant medications such as amphetamines and methylphenidate are the most commonly prescribed treatments for ADHD, however, they are not suitable for all patients. Some individuals do not respond well to stimulants, while others may experience side effects such as increased heart rate, anxiety or the potential for misuse and dependence. Non-stimulant alternatives exist, but they often have delayed onset and may be less effective for some patients. Given these limitations, there is a strong demand for new treatment options that offer both efficacy and a favorable safety profile.

A new approach to ADHD management

In response to this need for alternative treatments, researchers have been exploring new approaches to ADHD management. Axsome Therapeutics Phase 3 FOCUS trial evaluated solriamfetol as a potential treatment for adult ADHD. Originally developed to treat excessive daytime sleepiness associated with narcolepsy and obstructive sleep apnea, solriamfetol has gained attention for its potential in ADHD due to its unique mechanism of action. Unlike traditional stimulant medications, which primarily increase dopamine levels through direct release, solriamfetol is a dopamine and norepinephrine reuptake inhibitor (DNRI) with additional effects on the trace amine-associated receptor 1 (TAAR1) and serotonin 5-HT1A receptors.

The FOCUS trial enrolled 516 adults diagnosed with ADHD, who were randomly assigned to receive either 150 mg or 300 mg of solriamfetol, or a placebo, once daily for 6 weeks. The study successfully met its primary endpoint, demonstrating a statistically significant reduction in ADHD symptoms as measured by the Adult ADHD Investigator Symptom Rating Scale (AISRS). Patients treated with 150 mg of solriamfetol experienced a 17.7-point reduction in AISRS scores from baseline, compared to a 14.3-point reduction for those on placebo, reflecting a 45% mean reduction in ADHD symptoms.

Beyond symptom reduction, solriamfetol also improved overall ADHD severity, as assessed by the Clinical Global Impression of Severity (CGI-S) for ADHD. However, while the higher 300 mg dose showed improvements over placebo, these results did not reach statistical significance – suggesting that the 150 mg dose may be the optimal therapeutic level.

“The results of the FOCUS trial demonstrate that solriamfetol was able to reduce mean ADHD symptom burden by nearly 50%, which contributed to significant reductions in disease severity. These results are especially promising as part of a comprehensive wellness plan for individuals with ADHD,” said Mattingly.

“The symptom improvements observed with solriamfetol were accompanied by a favorable safety and tolerability profile. Based on these compelling data, solriamfetol has the potential to be an important new treatment option for adult patients living with ADHD,” he added.

Next steps for solriamfetol in ADHD

Axsome has not yet announced a regulatory filing timeline for FDA approval for solriamfetol. While the drug has demonstrated significant efficacy, further steps will be required before it can become widely available for ADHD treatment.

The biopharmaceutical company has planned a pediatric trial for later this year to assess the drug’s safety and efficacy across different age groups. If these trials are successful, solriamfetol could become an important treatment option for younger patients.

Compared to other emerging ADHD treatments, solriamfetol’s mechanism sets it apart from traditional stimulant medications. While newer non-stimulant treatments like Supernus’ Qelbree (viloxazine) have shown promise, solriamfetol’s efficacy data from the FOCUS trial suggests it could offer comparable benefits, potentially with a different side effect profile.

“We are pleased with the positive results of the FOCUS trial, which provide the first evidence from a multicenter controlled trial of the efficacy of solriamfetol in the treatment of ADHD,” said Dr. Herriot Tabuteau,  principal scientist, founder and CEO of Axsome Therapeutics.

“ADHD is a serious, heterogeneous and prevalent condition. We look forward to advancing the development of solriamfetol as a new, differentiated potential treatment for the millions of patients living with ADHD,” he added.

This article is a rework of a press release issued by Axsome Therapeutics. Material has been edited for length and content.