Neurovance Inc. today announced interim results from its phase 2a pilot study of EB-1020 SR in adult patients with all subtypes of ADHD. With the four week trial fully enrolled and dosing completed in the majority of patients, the results indicate a statistically significant improvement in ADHD symptoms. The 40 patient trial was led by Dr. Andrew J. Cutler at the Florida Clinical Research Center and is the first evaluation of the safety and efficacy of EB-1020 SR in a patient population.
The trial was a flexible-dose single-blind placebo lead-in design exploring doses ranging from 300 to 500 mg/day given as a divided dose BID. Specifically, the interim results demonstrated a 21.5 point improvement in the primary outcome measure at week four, a reduction in ADHD symptoms compared to baseline as measured by the ADHD Rating Scale IV (ADHD-RS-IV). These findings were statistically significant (p<0.0001). Additionally, improvement in ADHD symptoms was observed quickly, with 80% of the peak benefit observed by the second week of therapy.
"We could not be more pleased by these interim results," said Anthony A. McKinney, President and CEO of Neurovance. "By week four, 72% of all patients meet the generally accepted definition of a responder on two validated scales, the CGI-I and the ADHD-RS, and EB-1020 SR has been safe and well-tolerated thus far with most adverse events reported as both mild and transient."
The level of reduction in ADHD symptoms with EB-1020 SR was comparable to that observed in other adult ADHD trials investigating standard stimulant medications under similar trial conditions. EB-1020 SR, a triple reuptake inhibitor, modulates norepinephrine (NE), dopamine (DA) and, to a lesser extent, serotonin (5-HT) reuptake in a ratio of 1 to 6 to 14. EB-1020 SR has shown a low risk of abuse potential in preclinical studies and does not appear to be rewarding in man.
"EB-1020 SR is a hybrid between the stimulants and the non-stimulant, norepinephrine-only approach to ADHD," said Frank P. Bymaster, Chief Scientific Officer of Neurovance. "I was involved in the development of atomoxetine, the first non-stimulant approved for ADHD so I understand the strengths and the weaknesses of a norepinephrine-only medication. At the same time, stimulants are effective but they have issues as well. That is why we are excited about this hybrid approach: a potentially more effective non-stimulant with less risk of drug abuse or diversion than stimulants for adults with ADHD."
Adult ADHD affects as many as 10 million people in the US alone. In adults it can be a serious condition and can severely impair executive function, the ability to organize and plan effectively, hold a job, maintain a long-term relationship or even to safely drive a car. In adults, 75% of ADHD patients have at least one other psychiatric disorder alongside their ADHD. Neurovance is exploring EB-1020 SR's effects on several comorbidities including executive function, mood and emotional dysregulation as secondary endpoints in this study. Complete results from the trial are expected by the end of the first quarter 2014.
"Given the pernicious effects of untreated ADHD, novel treatment options are sorely needed for adults with the disorder," said Timothy E. Wilens, MD, of Massachusetts General Hospital and a leading ADHD expert. Dr. Wilens added, "These preliminary results of EB-1020 SR on ADHD symptoms and overall outcome are very encouraging and certainly warrant further exploration."
EB-1020 SR has shown a low risk of abuse potential in preclinical studies. Other triple reuptake inhibitors in development have been evaluated and have consistently demonstrated a low risk of abuse potential. Although a definitive abuse liability study has not yet been initiated with EB-1020 SR, a less restrictive level of scheduling, compared to stimulants, is anticipated.
According to IMS Health, the US ADHD market was valued at $10.4 billion in 2012, and is one of the fastest growing US pharmaceutical markets. The US prescription market is roughly equal in size between adults and children; however, prescriptions are growing at a rate nearly three times faster in adults. Although ADHD markets outside of the US are less well developed, they are growing rapidly. In 2012 IMS reported ADHD sales growing from $569 million in 2007 to just over $1 billion in 2011, a 16% compound annual growth rate.