Attention-deficit hyperactivity disorder (ADHD) can be addressed by several medicines already commercially available but there’s now another treatment option and it’s the first new FDA-approved drug of its type in more than a decade.
The FDA late Friday approved Supernus Pharmaceuticals’ drug viloxazine for the treatment of ADHD patients 6 to 17 years of age. The Rockville, Maryland-based company will market the once-daily, extended-release capsule under the name “Qelbree.”
ADHD drugs generally fall into one of two categories: stimulants and non-stimulants. According to the FDA, stimulant medications are believed to increase brain levels of dopamine, a brain chemical associated with motivation, attention, and movement. But stimulant medications can bring side effects such as headaches, high blood pressure, decreased appetite, and insomnia. Also, most stimulant ADHD drugs are classified as Schedule II substances because they pose the risk of abuse and dependence.
Non-stimulant ADHD drugs include atomoexetine, guanfacine, and clonidine. Clonidine’s approval was the most recent, coming in 2010. In some cases, stimulants and non-stimulants are prescribed together.
In developing Qelbree, Supernus has been vying to offer a drug that could work better than the non-stimulant ADHD drugs already on the market. Viloxazine was first approved in Europe in the 1970s as an antidepressant in Europe, but in a higher dose than Supernus’s version. From the standpoint of the FDA, the drug is a new chemical entity.
Viloxazine is a norepinephrine reuptake inhibitor, which means it blocks the absorption of norepinephrine, an excitatory brain chemical. The exact mechanism of the drug in ADHD is unclear, but Supernus said in its patent filings that the compound’s mechanism of blocking norepinehrpine may also enhance the release of another brain chemical called serotonin.
Supernus evaluated its drug in four placebo-controlled Phase 3 studies enrolling more than 1,000 patients: two studies in patients ages 6 to 11, and two more in patients 12 to 17. The main goal was to show a statistically significant reduction in ADHD symptoms according to a rating scale used to assess the disorder. Supernus reported preliminary data in 2018 showing that the drug met the study’s goal.
Last December, Supernus also announced positive results from a Phase 3 study testing its ADHD drug in adults. The company said Monday that it in the second half of this year it plans to ask the FDA to expand Qelbee’s approval to adults.
The Supernus drug was well tolerated in both the pediatric and adult clinical studies. But the drug’s approval comes with a boxed warning on its label cautioning that the medicine may cause suicidal thoughts. In clinical trials, the rates of suicidal thoughts and behavior were higher in children treated with the Supernus drug compared to those given a placebo. Supernus said that the increase in suicidal thoughts and actions may come within the first few months of treatment or when the dose is changed. The company added that parents and caregivers should be aware of such behaviors, and they should call a physician at the sign of any suicidal thoughts or behavior.
The Qelbree label also notes that the drug should not be taken by patients who are on certain anti-depressants, particularly monoamine oxidase inhibitors (MAOIs). A drug interaction between Qelbree and MAOIs could lead to life-threatening high blood pressure.
FDA approval of Qelbree comes later than Supernus had hoped. Last November, the company said the regulator declined the drug application, due to the move of a company laboratory that does analytical testing to a new location. No safety or efficacy issues with the drug were raised. Supernus said the drug application did not rely on that laboratory location and the company resubmitted its filing in February.
In a prepared statement, Jack Khattar, Supernus’s president and CEO, said that Qelbree provides an ADHD treatment option that is not a controlled substance while demonstrating efficacy and tolerability. The company plans to launch the drug later in the current quarter.
Photo: Waldemarus, Getty Images