Abbott Laboratories submits New Drug Application for tiagabine for partial seizures; studies show tiagabine is promising in the treatment of epilepsy.

ABBOTT PARK, Ill.--(HealthWire)--Dec. 1, 1995--Abbott Laboratories has submitted a New Drug Application with the U.S. Food and Drug Administration, seeking clearance for the use of tiagabine HCI as adjunctive therapy for partial seizures, a common form of epilepsy.

Tiagabine is one of a new class of compounds that affects the availability in the brain of gamma aminobutyric acid (GABA), a naturally occurring chemical that is thought to suppress the abnormal, repetitive pattern of central nervous system activity that can lead to seizures. Tiagabine appears to work by inhibiting neuronal reuptake of GABA, thereby prolonging the amount of time it is available at receptor sites.

Approximately 2.5 million people in the United States have some form of epilepsy, and an estimated 125,000 new cases are diagnosed each year. In 1987, it was estimated that approximately 800,000 patients in this country suffered from partial seizures. Of these patients, almost one-half did not respond adequately to currently available medications.

``Results of our research program demonstrate that tiagabine, when added to antiepilepsy drug (AED) regimens, can improve seizure control in patients with partial seizures,'' says Bruce Wallin, M.D., vice president of cardiovascular, immunoscience, and neuroscience development at Abbott Laboratories. Complex partial seizures, a type of partial seizure, are the most common form of seizures in adult patients with refractory chronic epilepsy and many patients require polytherapy.

Research results

The effectiveness of tiagabine as adjunctive therapy (added to other antiepilepsy drugs) was established in three multi-center, double-blind, placebo-controlled studies in patients with partial seizures. The median number of AEDs ever taken by these patients was six. In all three studies combined, 24 percent of patients on tiagabine achieved a 50 percent or greater reduction in the rate of complex partial seizures. Researchers also determined that 32 percent of patients on adjunctive therapy with tiagabine had a 50 percent or greater improvement in the rate of simple partial seizures. In addition, 45 percent of patients with secondary generalization achieved a 50 percent or greater reduction in the rate of seizures.

Safety

Some of the most common adverse events which occurred in greater than 1 percent of patients associated with tiagabine in combination with other antiepilepsy drugs include: dizziness, asthenia, nervousness, aphasia, depression, thinking abnormal, tremor, and abdominal pain. Importantly, there were no clinically important differences between tiagabine and placebo in changes on tests of neuropsychological and cognitive functioning.

Tiagabine is licensed from Novo Nordisk of Denmark.

Abbott Laboratories is a worldwide manufacturer of health care products, employing 50,000 people. In 1994, the company's sales and net earnings were $9.2 billion and $1.5 billion, respectively, with earnings per share of $1.87.

CONTACT: Abbott Laboratories, Abbott Park

Douglas Petkus, 708/938-3531

Laureen Cassidy, 708/938-7743