CHICAGO – The benefit from dual-antiplatelet therapy in high-risk patients following a myocardial infarction was especially apparent in post-MI patients with diabetes in a prespecified secondary analysis from a multicenter trial of ticagrelor with more than 21,000 patients.
Among post-MI patients with diabetes, treatment with ticagrelor plus aspirin led to an absolute 1.5% reduction in the rate of cardiovascular death, MI, or stroke during a median 33-month follow-up, compared with an absolute 1.1% cut in patients without diabetes, Dr. Deepak L. Bhatt said at the annual meeting of the American College of Cardiology. The relative risk reduction, compared with placebo was 16% in both the diabetes and no diabetes subgroups, statistically significant differences in both subgroups.
“Long-term treatment with ticagrelor reduced the composite of cardiovascular death, MI, or stroke in diabetic patients with a greater absolute risk reduction than in nondiabetic patients,” said Dr. Bhatt, professor of medicine at Harvard Medical School and executive director of Interventional Cardiovascular Programs at Brigham and Women’s Hospital in Boston. Treatment with ticagrelor plus aspirin in post-MI patients with diabetes also led to an increased number of major bleeding episodes, compared with patients on aspirin alone, but no excess of intracerebral hemorrhages or fatal bleeds, he noted.
This finding of a significant benefit from ticagrelor in post-MI patients with diabetes confirms similar, prior findings with other antiplatelet drugs (including clopidogrel, prasugrel, and vorapaxar) and prior findings with ticagrelor, Dr. Bhatt noted.
The new analysis used data collected in the Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin–Thrombolysis in Myocardial Infarction 54 (PEGASUS-TIMI 54) trial. The primary results from PEGASUS-TIMI 54 had shown that adding ticagrelor to aspirin treatment of high-risk post-MI patients, including those who both had or did not have diabetes, significantly cut the composite rate of cardiovascular death, MI, and stroke, compared with aspirin alone (N Engl J Med. 2015 May 7;372[19]:1791-800). The study group included 6,806 patients with diabetes (type 2 diabetes in 99% of these patients), and 14,355 without diabetes. All patients had their MI 1-3 years before entering the study.
Dr. Bhatt and his associates examined the incidence of the various clinical endpoints measured in the study among only the patients with diabetes divided into those who received any dosage of ticagrelor (60 mg b.i.d. or 90 mg b.i.d.) or placebo, and also among the patients without diabetes. In addition to the primary endpoint, the new analysis showed that the rate of cardiovascular death during follow-up was 3.9% in the diabetes patients on dual therapy and 5.0% among the diabetes patients on aspirin only, a 22% relative risk reduction with ticagrelor added that was statistically significant. In contrast, among patients without diabetes the rates of cardiovascular death between those on and not on ticagrelor only differed by 0.2%, a 9% relative risk reduction that was not statistically significant. The same pattern occurred for the endpoint of death from coronary artery disease.
Concurrent with Dr. Bhatt’s report, the results appeared in an article published online (J Am Coll Cardiol. 2016 Apr; doi: 10.1016/S0735-1097[16]30023-7).
A new study, THEMIS, is examining the safety and efficacy of combined ticagrelor and aspirin treatment in a lower-risk group of patients with diabetes, those with coronary artery disease who have not had a prior MI. Those results may be available in 2018.
PEGASUS-TIMI 54 was sponsored by AstraZeneca, the company that markets ticagrelor (Brilinta). Dr. Bhatt has been an advisor to Cardax and Regado Biosciences and has received research support from AstraZeneca and several other companies.