Otsuka Pharmaceutical Development & Commercialization and Otsuka Pharmaceutical have announced positive topline results from a Phase 3b clinical trial evaluating centanafadine XR in adults with attention-deficit/hyperactivity disorder (ADHD) and comorbid anxiety.

 

The investigational treatment, centanafadine—a first-in-class norepinephrine, dopamine, and serotonin reuptake inhibitor (NDSRI)—met its primary endpoint, showing statistically significant improvements in ADHD symptoms versus placebo at week 8, measured by the Adult Investigator Symptom Rating Scale (AISRS).

 

Patients receiving centanafadine once daily achieved a greater reduction in AISRS total scores compared with placebo. Separation from placebo was observed as early as week 1 and sustained throughout the 8-week study period.

 

Secondary outcomes also showed benefit. Anxiety symptoms improved significantly on the Hamilton Anxiety Rating Scale (HAM-A) at week 8, alongside other supportive secondary endpoints.

 

“Adults with ADHD and comorbid anxiety represent a substantial and particularly challenging population to treat,” said John Kraus, executive vice president and chief medical officer, Otsuka. “These results provide additional insight into centanafadine’s clinical profile and expand the evidence base supporting its potential in adults with ADHD across diverse patient presentations.”

 

The safety profile was consistent with prior studies, with the most commonly reported side effects including nausea, decreased appetite, diarrhea, insomnia, dry mouth, and vomiting.

 

Centanafadine is currently under regulatory review in the United States.

 

The randomized, double-blind, placebo-controlled Phase 3b trial enrolled 315 adults aged 18–65 with ADHD and comorbid generalized anxiety disorder and/or social anxiety disorder. The primary endpoint was change from baseline in AISRS total score versus placebo at week 8, with key secondary endpoints including changes in HAM-A scores and other ADHD-related measures.