Three anti-platelet drugs used in combination are safe

Three drugs, each of which works in a different way, are used in anti-platelet therapy to help prevent restenosis (the reclogging of blood vessels after they have been cleared with percutaneous coronary intervention or PCI) or thrombosis (obstruction of an artery or vein by a blood clot). The use of these platelet inhibitory drugs — cilostazol, clopidogrel and aspirin — has resulted in a significant reduction of thrombotic complications in the primary and secondary prevention of heart attacks. But is it safe to use these medications together — or in combination do they increase the risk of bleeding? And will patients comply with taking three pills?

In a poster session presented today at the American College of Cardiology’s 54th Scientific Sessions in Orlando, Florida, Emory researchers say the answer to both questions is “yes”.

The scientists analyzed data from the Cilostazol for RESTenosis (CREST) Trial, a randomized clinical trial testing the efficacy of cilostazol to prevent restenosis after PCI. Earlier results from CREST showed a 35% relative risk reduction in restenosis from 34% to 22% with cilostazol. The anti-thrombotic drugs Clopidogrel (75 mg daily for 30 days) and aspirin daily for 6 months were administered to all patients in the CREST trial while a total of 705 of these patients were randomized to cilostazol (354) or placebo (351) following successful angioplasty and stent implantation.

Twenty-nine patients experienced bleeding complications (17 major and 12 minor) but there was no significant difference in the rate of bleeding for patients who received aspirin plus clopidogrel plus cilostazol versus those who received aspirin plus clopidogrel. There was also no significant difference in type of bleeding (major or minor) experienced by these patients, no matter which drug therapy they were given.

“There was no evidence of increased risk of bleeding in patients treated with aspirin plus clopidogrel plus cilostazol and we also found that adherence to treatment was high,” says Emory Heart Center cardiologist William Weintraub, MD, Director of the Emory Center for Outcomes Research, who participated in the study. “This is good news because all three anti-platelet medications work in somewhat different ways and in combination they may prove to have more efficacy.”

In addition to Dr. Weintraub, the Emory research team included Jovonne K. Foster MS, Paul Kolm PhD, Grant T. Anderson, Karen M. Parker BS, John S. Douglas Jr. MD and Nancy VC Murrah RN,BSN. Drs. Douglas and Weintraub disclosed a commercial relationship with Otsuka American Pharmaceutical, Inc.