- Supernus has provided an early reveal of Phase 2b data of its non-stimulant ADHD drug in children, with statistically significant improvements in ADHD symptoms compared with placebo; changes from baseline were 19.0 points for 400 mg, 18.6 points for 300 mg and 18.4 points for 200 mg, compared with 10.5 for placebo.
- The study rolled over into an open-label extension, and 87% of patients chose to enter the open-label phase. Supernus anticipates moving SPN-812 (viloxazine) into a Phase 3 trial in 2017. The market opportunity for SPN-812 in ADHD is $2.5 billion.
- The next step for the Rockville, MD-based company will be to complete the data analysis and meet with the Food and Drug Administration about Phase 2a data from adults and the Phase 2b data from children.
ADHD treatment for children and adults is a busy market, but currently around 92% of the prescriptions are stimulants, Jack A. Khattar, president and CEO explained in the webcast and call on Tuesday announcing the topline results for the Phase 2b trial of SPN-812 in children with ADHD.
Supernus is trying to break into the non-stimulant market with SPN-812, a once daily, controlled-release formulation of viloxazine, a drug that was available for many years from Zeneca (now AstraZeneca) in Europe as an antidepressant, until it was withdrawn for business reasons.
The effect sizes in the SPN-812 study were between 0.55 and 0.63 for the 200-400 mg dose. Khattar described the SPN-812 data as robust and consistent, with a strong effect size not often seen in non-stimulant drugs in ADHD, which are generally around 0.4 to 0.5. Although these aren't as high as those seen in stimulant studies, stimulants are associated with side effects, and carry the potential of abuse.
"We are very excited about these results and that SPN-812 met the objectives of the study with an encouraging and strong clinical profile," said Khattar. "We believe SPN-812 has the potential of being a well differentiated treatment for ADHD that sets itself apart from current treatment options."
Supernus has three products in its clinical pipeline and the most advanced is SPN-810 (molindone) in Phase 3 in the treatment of impulsive aggression in ADHD. There are currently no products approved for this indication, and the drug has been granted fast track designation by the FDA in the ADHD population. As well as SPN-812 in Phase 2, Supernus is developing another formulation of viloxazine, SPN-809, for the treatment of depression. This is currently in Phase I.
The world ADHD market could be worth around $13.9 billion by 2024, predicts GlobalData, with a growth rate of around 8.5%. This is at least partly driven by the growing recognition of ADHD in adults. Many of the existing drugs are stimulants, which come with an associated risk of abuse and addiction.
Potential non-stimulant competitors include Sunovion's Phase 3 candidate for the treatment of ADHD in children and adults, and Alcobra's formulation of metadoxine until the Phase 3 trial was halted by the FDA. Lilly's Strattera (atomoxetine) is approved for use in children and adults, but it carries a boxed warning for suicidal ideation in children and adolescents. It's not clear yet whether there will be a similar requirement for SPN-812, but the only two serious adverse events reported in the study were easy tearfulness and intermittent irritability in a child receiving the 400 mg dose, and decreased appetite in another on the 200 mg dose. All other adverse effects were mild or moderate.