Neurogen believes that the bilayer tablet formulation of adipiplon being used in the study may not be performing as expected.
The company plans additional investigation of the bilayer tablet before proceeding further. In prior studies Neurogen has simultaneously administered various doses of both immediate release and controlled release forms of adipiplon.
The current study is the first trial in which it has used the two forms laminated together into one bilayer tablet. In previous testing in over 600 subjects, adipiplon has been well tolerated.
Stephen Davis, president and CEO of Neurogen, said: “Until we further assess the situation and determine whether there is a path forward we can and should take, we will carefully limit our resource commitments to this program. We remain focused on our ongoing Phase II studies with our dopamine partial agonist, aplindore, in Parkinson’s disease and in restless legs syndrome.”