The POPular AGE (POP AGE) trial was an open-label study featuring independent blinded adjudication of clinical events. The median age of participants was 77 years, and about one-quarter had a prior MI. It was basically an all-comers study in which 1,003 non-ST-elevation ACS patients age 70 or older at 11 Dutch medical centers were randomized within 3 days of hospital admission to 12 months of dual antiplatelet therapy with either ticagrelor or one of the two more potent antiplatelet agents. Although the choice of ticagrelor or prasugrel was left to the physician, it’s noteworthy that 94% of patients in the high-potency P2Y12 inhibitor study arm were discharged on ticagrelor. At 12 months, the adherence rate to the assigned regimen was 76% in the clopidogrel group and just 51% in what was essentially the ticagrelor arm. Bleeding was the number-one reason for the much higher discontinuation rate in the ticagrelor group, followed by initiation of oral anticoagulation and dyspnea.
The primary safety endpoint in POP AGE was the rate of major and minor bleeding as defined in the PLATO study. The rate was 17.6% with clopidogrel, compared with 23.1% in the ticagrelor group, for a highly significant 26% reduction in relative risk. Of note, the PLATO major bleeding rate was 4.4% with clopidogrel, versus 8% with ticagrelor/prasugrel.
The coprimary endpoint was net clinical benefit, defined as a composite of all-cause mortality, MI, stroke, and PLATO major and minor bleeding. The rate was 30.7% with ticagrelor and 27.3% in the clopidogrel group, for an absolute 3.4% risk difference favoring clopidogrel, which barely missed the prespecified cutoff for noninferiority. Indeed, even though the 12-month follow-up was 99.6% complete, Dr. Gimbel raised the possibility that when the results come in for the final 0.4% of the study population, the difference in net clinical benefit may reach significance.
In any case, she noted there was no between-group difference in the key secondary endpoint of death, MI, or stroke, with rates of 12.8% and 12.5% in the clopidogrel and ticagrelor groups, respectively.
“One might expect a higher ischemic event rate with clopidogrel compared to ticagrelor. However, in these elderly patients there was no difference between the two treatment strategies,” the cardiologist observed.
POP AGE is hailed as ‘a wake up call’
In an interview, Freek Verheugt, MD, PhD, professor emeritus of cardiology at Radboud University in Nijmegen, The Netherlands, called POP AGE “a very important study.”
“The problem with most studies in the elderly is that they are post hoc analyses from huge trials like PLATO and TRITON, and also the thrombolysis and primary PCI studies. The elderly do very well in those studies, because only the very fit elderly are included in the megatrials. It’s much more important to do a prospective randomized trial in the elderly only, and this is one of the very few done so far,” he observed.
Bleeding is a major problem in the elderly with ACS. It leads to more MIs, strokes, and increased mortality.
“Even minor bleeding is an issue,” Dr. Verheugt added. “Minor bleeding is a major problem, because patients who encounter minor bleeding – nose bleeds, gum bleeds, or even in their underwear – they do away with all drugs. They stop their antithrombotic, but they also stop their statin, their ACE inhibitor – their lifesavers – and that’s why they die.”
So is POP AGE a practice-changing study?
“No, of course not,” the cardiologist scoffed. “To be practice-changing you need several trials going in the same direction. But I think if there are more data prospectively accrued in the elderly alone, showing the same, then POP AGE would be practice-changing.”
“In my personal view, this study is a wake-up call. If you have an elderly, frail patient presenting with ACS, strongly consider good, old clopidogrel. Although people say that 30% of patients on clopidogrel don’t have appropriate platelet inhibition, that’s a laboratory finding. It’s not a clinical finding. POP AGE gave us a clinical finding showing that they do quite well,” he said.
Dr. Verheugt was on the independent data safety monitoring board for POP AGE, funded by ZonMw, a Dutch governmental research organization. Neither Dr. Verheugt nor Dr. Gimbel reported having any financial conflicts of interest.
SOURCE: Gimbel ME. ESC 2019, Abstract 84.