Cephalon, Inc., an international biopharmaceutical company, announced that data from its phase III clinical programme evaluating Gabitril (tiagabine hydrochloride) for the treatment of generalized anxiety disorder (GAD) did not reach statistical significance on the primary study endpoints.

Cephalon will conduct a complete analysis of the data to assist in its evaluation of future clinical development plans for Gabitril in other therapeutic areas.

Cephalon currently markets Gabitril in the United States and Europe. Gabitril is indicated as adjunctive therapy in adults and children 12 years and older in the treatment of partial seizures. In three multicenter, double-blind, placebo-controlled, parallel-group clinical trials and two placebo-controlled crossover studies, Gabitril significantly reduced the frequency of seizures in patients with epilepsy who took Gabitril as add-on therapy. In epilepsy patients, dosing with Gabitril is initiated at 4 mg dosed 2-4 times a day with food and titrated to a maintenance dose of 32-56mg/day in patients receiving hepatic enzyme-inducing anticonvulsants. The maximum dose in epilepsy patients is 32 mg in children and 56 mg in adults.

In clinical trials, Gabitril was well tolerated with the most common adverse events being mild to moderate in severity. The most common adverse events were dizziness, asthenia (weakness), somnolence, nausea, nervousness, tremor, abdominal pain, and impaired concentration.