Targacept ADHD drug fails phase II study

An investigational treatment for adults with attention deficit/hyperactivity disorder (ADHD) that is being developed through partnership between AstraZeneca and Targacept has failed to meet the primary endpoint of a phase II proof of concept trial.

Top-line results of the study showed that TC-5619 did not produce the targeted change from baseline on the Conners' Adult ADHD Rating Scale-Investigator Rated Total ADHD Symptoms score in adult non-smokers after four, eight and 12 weeks of dosing. Targacept plans to present the full results at an upcoming scientific meeting once the company has finished analysing the data.

"We continue to pursue a strategy of using initial phase II development to gain clinical insights that help identify the indications for which our compounds will be best suited for later-stage development," said J Donald deBethizy, Targacept's president and chief executive officer.

"While we did not see stimulant-like efficacy in this learning trial, the overall findings provide additional evidence that TC-5619 is active in a cognitively-impaired patient population, with the safety results adding to an impressive profile for a compound that has now been studied in more than 200 subjects."

TC-5619 performed well in a phase II clinical trial in cognitive dysfunction in schizophrenia, the results of which were originally announced in January and will be presented in April at the 13th International Congress on Schizophrenia Research. In addition, Targacept is currently conducting clinical and non-clinical studies designed to support potential phase II development of the product in Alzheimer's disease.

TC-5619, a highly selective alpha7 neuronal nicotinic receptor modulator, is subject to license by AstraZeneca under the companies' strategic collaboration agreement. AstraZeneca expects to make a decision on the licence option in the second quarter of this year.