HONOLULU – The combination also entails a similar risk of major bleeding, compared with aspirin and clopidogrel alone, according to results from the Cilostazol Stroke Prevention Study for Antiplatelet Combination (CSPS.com).
Dual-antiplatelet therapy with aspirin and clopidogrel reduced the rate of recurrent stroke in previous studies. The benefit of this drug combination is relatively short-lived, however, and long-term concomitant use of aspirin and clopidogrel entails a risk of major bleeding. Other data have indicated that cilostazol, which is approved by the Food and Drug Administration to alleviate intermittent claudication in patients with peripheral vascular disease, prevents stroke recurrence without increasing the incidence of serious bleeding, compared with aspirin, said Kazunori Toyoda, MD, PhD, who presented the results of the CSPS.com trial at the International Stroke Conference sponsored by the American Heart Association.
Dr. Toyoda of the National Cerebral and Cardiovascular Center in Osaka, Japan, and his colleagues randomized 1,879 high-risk patients at 8-180 days after the onset of noncardioembolic ischemic stroke identified on MRI to receive 81 or 100 mg aspirin or 50 or 75 mg clopidogrel alone, or a combination of cilostazol 100 mg twice daily with aspirin or clopidogrel. They conducted their open-label, parallel-group trial at 292 sites in Japan from December 2013 through March 2017.
To be considered at high risk, participants had to meet one or more of the following criteria: 50% or greater stenosis of a major intracranial artery, 50% or greater stenosis of an extracranial artery, and two or more vascular risk factors. The trial’s primary efficacy outcome was the first recurrence of ischemic stroke. Safety outcomes included severe or life-threatening bleeding.
The investigators ended the trial early because of a delay in recruiting patients. They enrolled 1,884 and randomized 1,879 of an anticipated 4,000 patients. At randomization, 41% in the dual-therapy group received aspirin and 59% clopidogrel, and in the monotherapy group, 40% received aspirin and 60% clopidogrel. Baseline characteristics were similar between the treatment groups. The population’s mean age was 70. Approximately 30% of patients were women.
During a median follow-up period of 17 months, ischemic stroke recurred in 29 of 932 patients receiving dual therapy including cilostazol for an annual rate of 2.2% and in 64 of 947 patients receiving monotherapy for an annual rate of 4.5% (hazard ratio, 0.49; 95% confidence interval, 0.31-0.76; P = .001). Severe or life-threatening bleeding occurred in 8 patients (0.6% per year) receiving dual therapy and 13 patients (0.9% per year) receiving monotherapy (HR, 0.66; 95% CI, 0.27-1.60; P = .354).
The study was funded by Otsuka Pharmaceutical, which manufactures cilostazol. Dr. Toyoda reported receiving support from Bayer Yakuhin, Daiichi Sankyo, Bristol-Myers Squibb, and Nippon Boehringer Ingelheim.
SOURCE: Toyoda K et al. ISC 2019, Abstract LB3.