Biotie, a specialized drug development company, has announced top-line data from a phase II study evaluating its dopamine beta hydroxylase inhibitor nepicastat (SYN117) in combat veterans suffering from post-traumatic stress disorder (PTSD). The study was funded by the US Department of Defense and conducted as an Investigator-initiated study in the United States using clinical trial material supplied by Biotie.

Treatment with nepicastat was not effective in relieving PTSD-associated symptoms when compared to placebo. Nepicastat was generally well tolerated.

"We are disappointed with the results of this trial and will work with the study investigators to analyze and understand the data in more detail before deciding on next steps with nepicastat in PTSD," said Timo Veromaa, president and CEO of Biotie. "Independent of these results, we will continue to develop nepicastat in cocaine dependence in partnership with the US National Institute of Drug Abuse (NIDA). We expect the first patients to be enrolled into a phase II study in Q1 2013."

The completed phase II study was a randomized, placebo-controlled, double-blind study conducted in 100 combat veterans fulfilling diagnostic criteria for PTSD. It was conducted at 4 VA Medical Centres in the United States, with Dr Lori Davis from Tuscaloosa VA Medical Centre as the Principal Investigator.

The subjects were randomized in a 1:1 ratio to receive either 120 mg/day nepicastat or matching placebo for six weeks under double-blind conditions. Thereafter, subjects could continue on open-label study drug for an additional eight weeks.

Efficacy was evaluated with the Clinician-Administered PTSD Scale (CAPS); the primary efficacy variable was the CAPS hyperarousal subscale (CAPS-D). Safety and tolerability were assessed with standard methods, including adverse event inquiries and laboratory analyses.

Nepicastat is an orally administered, potent and selective inhibitor of the enzyme dopamine beta hydroxylase (DBH), the enzyme responsible for the conversion of dopamine into norepinephrine. The compound has demonstrated potential as a treatment for cocaine dependence and PTSD. Nepicastat was licensed from Roche in 2007.

Biotie is focused on the development of drugs for neurodegenerative and psychiatric disorders (e.g. Parkinson's disease, Alzheimer's disease and other cognitive disorders, alcohol and drug dependence (addiction) and post-traumatic stress disorder), and inflammatory and fibrotic liver disease.