Otsuka’s Centanafadine Shows Promise in Phase III Pediatric ADHD Studies

ADHD_iStock, PeopleImages

Pictured: Girl student having trouble concentrating/iStock, PeopleImages

Otsuka Pharmaceutical on Friday posted top-line data from two Phase III studies, demonstrating that its attention deficit/hyperactivity disorder candidate centanafadine significantly improves symptoms in children and teenagers.

Friday’s readouts come from attention deficit/hyperactivity disorder (ADHD) trials that are largely similar in design, employing three arms and fixed high or low doses of centanafadine which were given compared to placebo on a double-blinded basis. The main difference is in the study populations: one enrolled adolescent participants between the ages of 13 and 17 years, while the other included children aged six to 12 years.

In the adolescent study, patients treated with high-dose centanafadine saw significantly better scores on the ADHD Rating Scale version 5 (ADHD-RS-5), a validated tool used to assess the severity of ADHD and the study’s primary endpoint. The average effect of both the high and low centanafadine doses was also significantly better than placebo.

Centanafadine was similarly effective in children. ADHD-RS-5 scores significantly improved in patients who were treated with high-dose centanafadine, and the average treatment effect in both high-dose and low-dose groups was likewise statistically better than placebo.

In the adolescent and pediatric trials, the benefits of high-dose centanafadine became apparent as early as the first post-baseline timepoint at week one, which was sustained for the rest of the study periods. However, both low-dose arms did not see significantly improved ADHD-RS-5 scores versus placebo.

In terms of safety, pooling data from both studies demonstrated a tolerability profile that was consistent with centanafadine’s broader clinical development program. The most common side effects included nausea, upper abdominal pain, somnolence and fatigue.

While the full results from both studies are not yet available, these data “demonstrate centanafadine has the potential to offer a new treatment option for children and adolescents who live with ADHD,” John Kraus, chief medical officer of U.S. subsidiary Otsuka Pharmaceutical Development and Commercialization, said in a statement.

Otsuka will submit complete data and analyses from both trials for scientific publication. The company will also use these findings, along with clinical pharmacology studies and long-term stability data, to build a New Drug Application for centanafadine in this indication.

Friday’s ADHD readout comes months after Otsuka and partner Sumitomo Pharma suffered two late-stage defeats in another psychiatric indication. In July 2023, the companies announced that its investigational TAAR1 agonist ulotaront failed the Phase III studies DIAMOND 1 and DIAMOND 2 in schizophrenia patients with acute psychosis.

Tristan Manalac is an independent science writer based in Metro Manila, Philippines. He can be reached at or

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