Strokes and Transient Ischemic Attacks Occurrence During Annual Dual Antiplatelet Therapy.

BACKGROUND: The incidence of stroke/TIA during annual dual antiplatelet therapy (ADAPT) for acute coronary syndrome (ACS) remains high. Some evidence suggests that shorter than ADAPT may diminish such risk, still providing adequate vascular protection. However, the precise timing of strokes/TIA occurrences during ADAPT is unclear but may be important for determining optimal preventive treatment duration. STUDY QUESTION: The precise timing of secondary cerebrovascular events over ADAPT. STUDY DESIGN: Access was gained to the FDA-issued Platelet Inhibition and Outcomes (PLATO) trial data set on which post hoc analyses of stroke/TIA timing after ticagrelor and clopidogrel on top of aspirin was explored. MEASURES AND OUTCOMES: Events were counted and plotted over time from day 1 till day 365 after the index ACS event. RESULTS: Among 18,624 enrollees, 252 strokes and 49 TIAs were reported. After the exclusion of entries with missing dates, unclear randomization codes, and events beyond 1-year follow-up, 238 strokes and 45 TIAs were analyzed. Overall, most frequent strokes/TIAs occurred within the first day after qualifying ACS, with the gradual declines after day 7 and day 40 reaching background counts thereafter. The strokes/TIAs patterns did not differ much between P 2 Y12 inhibitors except for twice more events at day 1 and excess exclusions after day 365 in the ticagrelor arm. CONCLUSIONS: Most cerebrovascular events emerged very early after ACS despite ADAPT. This large hypothesis-generating evidence may justify shorter than the ADAPT duration after ACS. Twice more events at day 1 and excess late ticagrelor exclusions in PLATO deserve further scrutiny. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00391872.

Time Course of Death After Acute Coronary Syndrome Treated With Dual Antiplatelet Therapy for 1 Year.

BACKGROUND: Excess mortality remains the cornerstone concern despite dual antiplatelet therapy (DAPT) after acute coronary syndrome. Some data suggest that shorter periods than 12 months of DAPT diminish bleeding risks yet still provide adequate vascular protection and improving survival. However, the precise timing of deaths after acute coronary syndrome has not been mapped in many studies. This knowledge may be critical for defining optimal treatment duration. METHODS: Access was gained to the data set for the Platelet Inhibition and Outcomes (PLATO) trial, which was issued by the Food and Drug Administration, in which post hoc analyses of timing of death events during DAPT (with either aspirin/ticagrelor or aspirin/clopidogrel) were performed. All-cause individual deaths were counted and plotted over time from day 1 to day 365 after the index event. RESULTS: Among 18,624 enrollees, 938 total deaths were reported to the Food and Drug Administration in PLATO. After exclusion of deceased patients with missing dates, randomization errors, and deaths beyond 1 year of follow-up, 913 fatalities (509 after clopidogrel and 404 after ticagrelor) were analyzed. The PLATO records did not indicate where exactly deaths occurred making impossible to triage in the hospital versus outpatient fatalities. Most frequent deaths occurred within the Day 1 (n = 41); Day 2 (n = 48); and Day 3 (n = 33) and overall during the first week (n = 202; 22.1%) after the index acute coronary syndrome, with a gradual decline after Day 10 and Day 60, reaching background counts after Day 220. CONCLUSION: Focusing on mortality reduction, this large data set may support a shorter than 12 months' duration of DAPT.

Impact of the reporting source on Platelet Inhibition and Treatment Outcomes (PLATO) trial deaths.

BACKGROUND: Platelet Inhibition and Clinical Outcomes (PLATO) was a multicenter, randomized double-blind trial assessing efficacy and safety of ticagrelor versus clopidogrel in patients with acute coronary syndrome. The reported mortality benefit of ticagrelor in the PLATO trial has been challenged for over decade, and never confirmed in later trials. OBJECTIVE: To compare if there were any differences when deaths were reported to the FDAby the sponsors or by independent Contract Research Organizations (CRO). METHODS: We obtained the complete PLATO deaths dataset reported to the FDA and revealed that some events were inaccurately reported favoring ticagrelor. The entire FDA list contains precisely detailed 938 PLATO deaths. The CRO reported outcomes from the USA, Russia, Georgia, and most of Ukraine, while sites in 39 other countries were controlled by the trial sponsors. We compared vascular- (code "11"), non-vascular- (code "12"), and unknown (code "97") deaths triaged by the reporting source. RESULTS: Overall, most PLATO deaths were vascular (n=677), less non-vascular (n=159) andunexpectedly many of "other" (n=7) or "unknown" (n=95) origin reported either by sponsors (n=807) or CRO (n=131). The trial sponsors reported more clopidogrel deaths from vascular (313 vs.239), non-vascular (86 vs.58) and unknown (53 vs. 26) causes.In contrast, CRO-monitored sites reported significantly (72 vs. 53; p<0.01) more ticagrelordeaths than after clopidogrel from vascular (51 vs.39), non-vascular (8 vs.7) and unknown (10 vs. 4) causes. CONCLUSION: Deaths were reported differently by sponsors and CRO within the same trial. Since some deaths were misreported by PLATO sponsors, only the CRO data seems mostly reliable. Among all countries, the CRO - reported PLATO-USA outcomes represent the largest and most realistic dataset of realistic evidence suggesting ticagrelor inferiority to clopidogrel for all primary endpoint components including vascular death.