AstraZeneca may not continue studying ADHD candidate AZD1446 after it failed to improve symptoms of the condition in a Phase II study. The study was one of several early clinical trial designed by AstraZeneca to obtain a signal of efficacy to guide dosing in potential later-stage development of AZD1446 in either or both of Alzheimer's disease and ADHD. AZD1446 is a selective modulator of the alpha4beta2 neuronal nicotinic receptor and was licensed by Targacept to AstraZeneca pursuant to a 2005 collaboration agreement.
The multi-center, randomized, double-blind, placebo-controlled, cross-over trial assessed the efficacy, safety and pharmacokinetics of two weeks of treatment with AZD1446 versus placebo. Each subject was classified as a user or non-user of nicotine products. Non-nicotine users received placebo and two out of three oral AZD1446 dose regimens, and nicotine users received placebo and two oral AZD1446 dose regimens. However, in the study AZD1446 did not improve core symptoms of ADHD.
"While we are disappointed in the results on the primary outcome measure in this ADHD trial, we are encouraged by the memory and learning findings from the CogState test battery and believe they support further study of AZD1446 as a treatment for Alzheimer's disease," says J. Donald deBethizy, Targacept's president and CEO.
A decision by AstraZeneca as to potential future development of AZD1446 in Alzheimer's disease is expected in the coming months.
Targacept was spun out of R.J. Reynolds Tobacco Holdings in 2000. The company develops drugs based on its understanding of nicotinic receptors to treat diseases of the central nervous system--Alzheimer's, chronic depression, adult attention deficit hyperactivity disorder, cognitive dysfunction in schizophrenia and inflammatory disorders, the Winston-Salem Journal notes. Targacept's shares fell five percent premarket at $21.84, the Wall Street Journal reports.