Neurogen has suspended dosing in a Phase II/III trial of its insomnia drug adipiplon after registering next day side effects. Researchers had been dosing patients with various amounts of immediate and controlled-release forms of the therapy and this was the first trial to use a combination of both. Researchers said the side effects could be attributed to the formulation that was used, noting that the drug had been well tolerated previously by 600 volunteers.
"We are disappointed by this setback," said Stephen R. Davis, Neurogen's president and CEO. "We do not yet know whether there is a path forward with lower doses of the existing formulation or whether further formulation development would be required. 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."
- read the Neurogen's release