PRESS RELEASE: Study Protocols Will be Amended in Two Small Early-Phase Prasugrel Studies

Study Protocols Will be Amended in Two Small Early-Phase Prasugrel Studies

Enrollment temporarily suspended until approval of amendments, which may include adjustments in dosing for certain subpopulations

TOKYO, Japan and INDIANAPOLIS, Oct 24, 2007 -- Daiichi Sankyo Company, Limited (TSE: 4568) and Eli Lilly and Company (NYSE: LLY) today announced that enrollment of new patients and administration of the study drug in two small prasugrel-related pharmacodynamic clinical trials are being suspended until protocol amendments can be completed and approved. The amendments are due to preliminary results from pharmacokinetic analyses, including patients and healthy subjects/volunteers, indicating that a dose adjustment may be appropriate for certain subpopulations.

These protocol amendments should not be interpreted to represent the outcome of the overall prasugrel clinical development program.

The two small Phase II pharmacodynamic studies compare the levels of inhibition of platelet aggregation (IPA) in patients with coronary artery disease taking the investigational antiplatelet agent prasugrel or clopidogrel (Plavix®). Neither study has an efficacy endpoint. Patient enrollment will resume as soon as additional analyses of pharmacokinetic and clinical data are completed, and the protocols are amended and approved by institutional review boards.

"We are suspending enrollment in these two small pharmacodynamic trials so that we can amend current protocols," said J. Anthony Ware, M.D., Lilly cardiovascular platform leader for prasugrel. "These amendments are strictly protocol-related and do not provide a basis for inferring overall outcomes of other prasugrel trials."

Cardiovascular disease is the leading cause of death in the U.S. and worldwide, killing 16.7 million people each year.(i) Acute heart attacks and unstable angina, called acute coronary syndrome, affect more than 840,000 Americans each year and 800,000 in Europe.(ii,iii) Utilizing current medical interventions and treatments, 300,000 people continue to experience recurrent heart attacks and 450,000 people die from heart attacks annually in the U.S.(iv)

About prasugrel

Daiichi Sankyo Company, Limited (TSE: 4568), and Eli Lilly and Company (NYSE: LLY) are co-developing prasugrel, an investigational oral antiplatelet agent invented by Daiichi Sankyo and its Japanese research partner Ube Industries, Ltd., as a potential treatment, initially for patients with acute coronary syndrome undergoing PCI. Prasugrel works by inhibiting platelet activation and subsequent aggregation by blocking the P2Y12 adenosine diphosphate (ADP) receptor on the platelet surface. Antiplatelet agents prevent platelets from clumping or sticking together, which can result in clogged arteries and may lead to heart attack or stroke.

About Daiichi Sankyo Company, Limited

Daiichi Sankyo Company, Limited was established on Sept. 28, 2005, as the joint holding company of two major Japanese pharmaceutical companies - Sankyo Co., Ltd., and Daiichi Pharmaceutical Co., Ltd. Daiichi Sankyo is a global pharmaceutical innovator, continuously generating innovative drugs and services and maximizing its corporate value. Both companies have used their cumulative knowledge and expertise in the field of cardiovascular disease as a foundation for developing an abundant product lineup and R&D pipeline. For further details, please refer to the company Web site at www.daiichisankyo.co.jp/eng [1].

About Eli Lilly and Company

Lilly, a leading innovation-driven corporation, is developing a growing portfolio of first in class and best-in-class pharmaceutical products by applying the latest research from its own worldwide laboratories and from collaborations with eminent scientific organizations. Headquartered in Indianapolis, Ind., Lilly provides answers -- through medicines and information -- for some of the world's most urgent medical needs. Additional information about Lilly is available at www.lilly.com [2].

P-LLY

This press release contains certain forward-looking statements about the potential of the investigational compound prasugrel (CS-747, LY640315) and reflects Lilly's current beliefs. However, as with any pharmaceutical compound under development, there are substantial risks and uncertainties in the process of development and regulatory review. There is no guarantee that the compound will receive regulatory approval, or that the regulatory approval will be for the indication(s) anticipated by the company. There is also no guarantee that the compound will prove to be commercially successful. For further discussion of these and other risks and uncertainties, see Lilly's filing with the United States Securities and Exchange Commission. Lilly undertakes no duty to update forward-looking statements. Plavix® is a registered trademark of Sanofi-Synthelabo Inc.