Eisai Announces Positive Results of Phase III Trial for Perampanel in Epilepsy

Tokyo, Aug 24, 2010 (JCN Newswire via COMTEX) -- Eisai Co., Ltd. announced today that results of a Phase III study in epilepsy patients with refractory partial seizures demonstrate the clinical benefits of the novel investigational compound E2007 (generic name: perampanel). Discovered and developed by Eisai, perampanel is a first-in-class drug with a unique mechanism that selectively and non-competitively antagonizes AMPA-type glutamate receptors.

The global study (Study 306), conducted primarily in Europe and Asia, was a multi-center, randomized, double-blind, placebo-controlled, dose escalation, parallel-group study. The study consisted of 706 patients from 25 countries who were randomized to placebo or one of three perampanel doses (2 mg, 4 mg or 8 mg). Patients randomized to receive perampanel started on 2 mg doses, then remained on 2 mg or increased dosage weekly in 2 mg increments to their randomized doses of 4 mg or 8mg.

Findings demonstrated that perampanel was effective in reducing median seizure frequency, and increasing responder rates (the percentage of patients who experienced a 50% or greater reduction in seizure frequency), the study's two primary outcome measures, with high statistical significance in 4 mg and 8 mg doses compared to placebo. A linear trend for dose response was also highly statistically significant. The most frequently observed adverse events were dizziness, somnolence and headache, and the study confirmed that perampanel was well-tolerated.

Study 306 is the first in a series of Phase III clinical trials being conducted as part of Eisai's global development program for perampanel and two more Phase III studies are currently underway. Final results of all three studies are expected to be available within one year. Based on these results, Eisai plans to submit regulatory applications to the health authorities in the United States and the European Union before the end of Fiscal 2011.

Eisai defines neurology as a therapeutic area of focus and is committed the development of treatments such as perampanel, through which it seeks to make further contributions to addressing the diversified needs of and increasing the benefits provided to epilepsy patients and their families.

About E2007 (Perampanel)

Discovered and developed by Eisai, perampanel (generic name) is a novel investigational agent currently under development as a potential treatment for epilepsy, neuropathic pain, multiple sclerosis and migraine prevention. The compound selectively antagonizes the AMPA receptor, a type of receptor to which the neurotransmitter glutamate binds, and by preventing the excessive influx of calcium into brain cells, it suppresses the overactivity of excitatory nerves, thereby correcting excitatory-inhibitory nerve imbalance and inhibiting neuronal cell death.

About Study 306 Global Placebo-controlled Phase III Study

Indication:         Epilepsy patients with refractory partial-onset
Objective:          To evaluate the efficacy, safety and tolerability
                    of three doses of perampanel (2 mg, 4 mg and 8 mg
                    doses) in comparison to placebo as an adjunctive
                    treatment in epilepsy patients with refractory
                    partial seizures
Treatment groups:   E2007 2 mg, 4 mg, 8mg, placebo
Dosing duration:    19 weeks
Conducted in:       25 countries
Primary endpoint:   Percent change in seizure frequency* per 28 days
                    cycle in the maintenance period relative to the
                    pre-randomization phase
* United States:    Median seizure frequency
European Union:     Responder rate (percentage of patients who exper-
                    ienced a 50% or more reduction in seizure frequency)

About Eisai

Eisai Co., Ltd. (TSE: 4523; ADR: ESALY) is a research-based human health care company that discovers, develops and markets products in more than 30 countries. Through a global network of research facilities, manufacturing sites and marketing subsidiaries, Eisai actively participates in all aspects of the worldwide health care system. Eisai employs more than 8,000 people worldwide. For more information, please visit www.eisai.co.jp .