Tokyo, Japan -- Otsuka Pharmaceutical Co., Ltd. (Head Office: Chiyoda-ku, Tokyo, Japan; President: Taro Iwamoto) today announced that the results of CSPS II^*, a large-scale clinical trial of cilostazol, were presented on February 26 in a late-breaking science session at the American Stroke Association's International Stroke Conference held in San Antonio, Texas. According to the report, patients taking cilostazol were less likely to suffer a stroke or develop bleeding requiring hospitalization compared to patients taking aspirin.

• * CSPS II: Cilostazol Stroke Prevention Study II

CSPS II was launched in December 2003 to investigate the efficacy of cilostazol in preventing recurrence of cerebral infarction and the safety of long-term administration of cilostazol (100mg, twice daily) in patients with cerebral infarction (excluding cardiogenic cerebral embolism) in a multi-center, double blind, parallel-group comparison with aspirin (81mg, once daily). The researchers analyzed results from 2,672 ischemic stroke patients treated in 278 institutions in Japan. Patients were followed through 2008. All patients had suffered non-cardioembolic ischemic stroke within 26 weeks of enrolment and their symptoms had remained stable.

In the randomized, double-blind study of nearly 2,700 patients with non-cardioembolic ischemic stroke, those treated with cilostazol were 25.7% less likely to suffer from a stroke than those who received aspirin, according to the presentation in the late-breaking science session at International Stroke Conference. Other findings shown below were also obtained in CSPS II.

• Strokes occurred in 82 of 1,337 cilostazol-treated patients and in 119 of 1,335 aspirin-treated patients.
• A hemorrhagic stroke or hemorrhage that required hospitalization occurred in 23 patients taking cilostazol and 57 of those receiving aspirin - a significant difference.

"This study demonstrated for the first time that cilostazol significantly reduces the risk of recurrent ischemic stroke and the incidence of serious cerebral hemorrhage, compared to aspirin," said Yukio Shinohara, M.D., lead author of the study and hospital director at Federation of National Public Service Personnel Mutual Aid Associations Tachikawa Hospital in Tokyo, Japan."The primary implication of this trial is that the risk of re-attack of ischemic stroke in patients can be reduced without increasing the incidence of hemorrhage by oral administration of cilostazol. During the trial, we noted the incidence of recurrent stroke was very low, so we did not expect that there would be differences between the recurrence rate of stroke in the cilostazol and aspirin groups. However, the results showed a significant reduction in the recurrence rate, which surprised us. Although some of relatively minor complications other than bleedings were observed more in cilostazol-treated patients, while aspirin is used worldwide including Japan to prevent ischemic strokes, the findings in CSPS II provide us a significant impact on future clinical practice for the treatment of patients with ischemic stroke."

Otsuka Pharmaceutical Co., Ltd. strives to contribute to the health of people around the world based on its corporate philosophy of 'Otsuka-people creating new products for better health worldwide.'

Outline of CSPS II (Cilostazol Stroke Prevention Study II)

About Cilostazol

Cilostazol (Pletaal^®) was discovered and developed independently by Otsuka Pharmaceutical Co., Ltd. and launched in 1988 with improvement of ischemic symptoms including ulcers, pain and coldness associated with chronic arterial obstruction as the indication in Japan. In April 2003, secondary prevention of cerebral infarction (excluding cardiogenic cerebral embolism) was approved as the additional indication.