How It Works and Side Effects: Complete Guide

Simtriyo (centanafadine) has been approved by the U.S. Food and Drug Administration as a daily oral medication to treat attention deficit hyperactivity disorder in children ages 6 and older, teens, and adults, according to drug company Otsuka. As the first ADHD medication in its class, the drug offers a new alternative for patients who do not experience sufficient symptom improvement with existing stimulants like Adderall.

FDA Approval Details and Patient Population for Simtriyo

The FDA greenlit Simtriyo to serve children ages 6 and older, adolescents, and adults. Otsuka expects the medication to become commercially available to the public before the end of the year, though specific pricing details remain unannounced. Mai Uchida, MD, a child and adult psychiatrist at Mass General Brigham and an associate professor of psychiatry at Harvard Medical School in Boston, points out that new options are vital because current treatment approaches leave major gaps for many individuals.

Clinical Trial Results and Efficacy Data

Clinical trials evaluated Simtriyo across different age groups, tracking symptom changes using the ADHD Rating Scale–5 questionnaire. In a phase 3 trial focusing on adults with ADHD and anxiety, participants taking a 280-milligram once-daily dose experienced statistically significant improvements as early as one week compared to a placebo group, according to trial data. For children ages 6 to 12, a high dose led to a reduction of 18 points or more on the ADHD-RS-5 for 34 percent of participants, versus 23 percent for those taking a placebo, with similar trends observed in a separate trial of about 450 teenagers.

Comparing Simtriyo With Traditional Stimulant Medications

Traditional stimulant medications primarily impact dopamine and norepinephrine activity, while nonstimulants generally target norepinephrine alone. Simtriyo differentiates itself by inhibiting the reuptake of norepinephrine, dopamine, and serotonin simultaneously. Kelly Johnson-Arbor, MD, a toxicologist at MedStar Health in Washington, DC, explains that targeting serotonin addresses functions like emotional regulation, attention, and impulsivity. For patients suffering from intolerable side effects, anxiety, sleep disruptions, cardiovascular worries, or misuse risks associated with stimulants like amphetamine and dextroamphetamine, centanafadine provides an alternative pathway, according to Dr. Uchida.

Potential Side Effects and Who Should Avoid Treatment

Clinical trials showed that Simtriyo side effects are largely mild to moderate, with fewer than 8 percent of participants dropping out of studies due to adverse events. Commonly reported reactions include decreased appetite, nausea, headache, and rash. While children struggling to gain weight on stimulants might benefit from the switch, Neha Sharma, DO, chief of child and adolescent psychiatry at Tufts Medical Center in Boston, warns that the drug may prove too activating for certain children with pre-existing anxiety. It is also unsuitable for patients who cannot tolerate selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, or bupropion.

Frequently Asked Questions About Simtriyo

Simtriyo is an oral prescription medication approved by the FDA to treat attention deficit hyperactivity disorder in children ages 6 and older, teenagers, and adults, according to Otsuka.

How does Simtriyo work differently than Adderall?

While stimulant drugs like Adderall primarily affect dopamine and norepinephrine, Simtriyo acts as a norepinephrine, dopamine, and serotonin reuptake inhibitor, incorporating serotonin-targeting mechanisms that influence emotional regulation and attention, according to Dr. Johnson-Arbor.

Clinical trials identified common side effects including decreased appetite, nausea, headache, and rash, with the majority reported as mild to moderate in severity.

When will Simtriyo be available to patients?

Otsuka expects the medication to hit the market before the end of the year, though a precise release date and pricing details have not yet been released.