Eisai Receives Complete Response Letter from FDA for Rabeprazole Sodium Extended-Release Capsules

Eisai announced that the company received a Complete Response Letter from the United States Food and Drug Administration (FDA) regarding the New Drug Application (NDA) of rabeprazole sodium extended-release capsules, 50 mg, an investigational proton pump inhibitor (PPI) under review for the healing and long-term maintenance of healing and symptom resolution of erosive gastroesophageal reflux disease (GERD), and for the treatment of daytime and nighttime heartburn and other symptoms of non-erosive GERD.

The FDA issues a Complete Response Letter to indicate that the review cycle of an application is complete and the application is not ready for approval. Eisai will work with the FDA to address the requirements of the Complete Response Letter for the approval of rabeprazole sodium extended-release capsules, 50 mg.

Rabeprazole sodium extended-release capsules, 50 mg, is being evaluated as a new formulation that combines two different drug releasing mechanisms in one capsule to treat patients with GERD. An estimated 19 million Americans have GERD,

commonly known as acid reflux disease, which is a medical condition characterized by persistent, frequent heartburn and regurgitation due to reflux of stomach acid into the esophagus. Some patients develop erosive GERD, in which there are breaks in the lining of the esophagus, the passage that connects the mouth to the stomach.

Eisai Inc.

Eisai Inc. was established in 1995 and is ranked among the top-20 U.S. pharmaceutical companies (based on retail sales).

The company began marketing its first product in the United States in 1997 and has rapidly grown to become a fully integrated pharmaceutical business with fiscal year 2009 (year ended March 31, 2010) sales of approximately $3.9 billion. Eisai’s areas of commercial focus include neurology, gastrointestinal disorders and oncology/critical care. The company serves as the U.S. pharmaceutical operation of Eisai Co., Ltd.

Eisai has a global product creation organization that includes U.S.-based Massachusetts, New Jersey, North Carolina and Pennsylvania as well as manufacturing facilities in Maryland and North Carolina. The company’s areas of R&D focus include neuroscience; oncology; vascular, inflammatory and immunological reaction; and antibody-based programs. For more information about Eisai, please visit www.eisai.com.

Eisai Co., Ltd.

Eisai Co., Ltd. is a research-based human health care (hhc) company that discovers, develops and markets products throughout the world. Through a global network of research facilities, manufacturing sites and marketing subsidiaries, Eisai actively participates in all aspects of the worldwide healthcare system. Eisai employs approximately 11,000 employees worldwide.