Reviews/P2Y12 Antiplatelets/Ticagrelor increases major bleeding vs clopidogrel in ACS patients
Tca · P2Y12-TCA-02 · v2
Borderline: within 4 points of the Likely/Uncertain boundary, so a re-grade could land either side.
The question is whether ticagrelor causes more serious bleeding than clopidogrel in people treated for a heart attack or unstable chest pain. In the large trial that defines this comparison, the overall rate of serious bleeding was essentially the same on both drugs, but a specific category of bleeding not related to bypass surgery was clearly higher on ticagrelor [15], and the same pattern appeared in the trial's non-ST-elevation subgroup [11]. Studies in older patients, both a trial [6] and a large real-world registry [8], found more bleeding on ticagrelor. Other analyses, including a kidney-function subgroup [17] and a Medicare cohort [12], found no clear difference in total serious bleeding. The evidence points in one direction, more bleeding with ticagrelor, but how strongly depends on which type of bleeding and which patients you look at.
In the pivotal ACS trial, ticagrelor and clopidogrel had similar total major bleeding (11.6 vs. 11.2%; P = 0.43), but ticagrelor had higher non-CABG major bleeding (4.5 vs. 3.8%, P = 0.02) and non-procedure-related major bleeding (3.1 vs. 2.3%, P = 0.05) [15]. The non-ST-elevation subgroup reproduced this split: similar overall major bleeding (13.4 vs. 12.6%; HR 1.07; 95% CI = 0.95-1.19) with higher non-CABG major bleeding (4.8 vs. 3.8%; HR 1.28; 95% CI = 1.05-1.56) [11]. In patients aged 70 or older, bleeding was significantly lower with clopidogrel (18% vs. 24%; HR 0.71, 95% CI 0.54 to 0.94) [6], and in a registry of patients aged 80 or older ticagrelor carried a higher bleeding risk (HR 1.48, 95% CI 1.25-1.76) [8]. By contrast, the kidney-function subgroup (15.1% vs. 14.3%; HR 1.07, 95% CI 0.88 to 1.30) [17] and the nonfrail Medicare cohort (HR 1.22, 95% CI 0.98-1.51) [12] showed no significant difference in total major bleeding. The contested point: The evidence divides on bleeding definition: ticagrelor's increase is significant for non-CABG and non-procedure-related major bleeding [15] but not for total major bleeding in the pivotal trial [15] or its renal subgroup [17]. It also divides on population, with the strongest significant signals coming from elderly and observational settings [6], [8] rather than the all-ACS primary endpoint.
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The pivotal registrational RCT (PLATO, [15]) found NO significant difference in total major bleeding (PLATO major 11.6 vs 11.2%, P=0.43; TIMI major 7.9 vs 7.7%, P=0.56). The unqualified claim 'increases major bleeding' overreaches the primary endpoint; the significant increase is confined to the non-CABG/non-procedure-related subcategory.
The PLATO renal subgroup [17] and the nonfrail Medicare cohort [12] are null for total major bleeding (HR 1.07 CI 0.88-1.30; HR 1.22 CI 0.98-1.51), directly undercutting a blanket increase.
Where it remains uncertain. Total major bleeding was not significantly increased in the pivotal trial (11.6 vs. 11.2%; P = 0.43) [15], the renal subgroup (HR 1.07, 95% CI 0.88 to 1.30) [17], or the nonfrail Medicare cohort (HR 1.22, 95% CI 0.98-1.51) [12].
Aleatory
Fatal and procedure-related bleeding rates were low and did not differ, so chance variation limits what can be concluded about the most serious bleeds [15].
Epistemic
Three of six included sources [11], [15], [17] analyse the same PLATO trial, so the apparent replication overstates how many independent studies exist.
Inferential
The verdict depends on whether 'major bleeding' means total major (null in [15], [17], [12]) or the non-CABG/spontaneous subcategory (significantly higher in [15], [11]).
The load-bearing papers from a corpus of 17, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Elderly NSTE-ACS RCT: ticagrelor significantly increases bleeding vs clopidogrel.
“Primary bleeding outcome was significantly lower in the clopidogrel group (88 [18%] of 500 patients) than in the ticagrelor group (118 [24%] of 502; hazard ratio 0·71, 95% CI 0·54 to 0·94; p=0·02 for superiority).”
Panel auditInternal validity: medium · scope of inference: NSTE-ACS patients aged 70 or older, clopidogrel versus ticagrelor, PLATO major-or-minor bleeding.Key limitations: open-label · elderly-only population · bleeding endpoint is PLATO major or minor, not major alone
Large registry: significantly higher bleeding with ticagrelor in elderly MI (observational).
“Ticagrelor was associated with a 17% and 48% higher risk of death (HR, 1.17 [95% CI, 1.03-1.32]) and bleeding (HR, 1.48 [95% CI, 1.25-1.76]), but a lower risk of MI (HR, 0.80 [95% CI, 0.70-0.92]) and stroke (HR, 0.72 [95% CI, 0.56-0.93]).”
Panel auditInternal validity: medium · scope of inference: Elderly MI patients (primarily ≥80 years) discharged on aspirin plus ticagrelor or clopidogrel.Key limitations: observational, residual confounding · elderly-weighted population
Replicates the total-vs-non-CABG dissociation in NSTE-ACS.
“Major bleeding rate was similar between treatment groups (13.4 vs. 12.6%; HR 1.07; 95% CI = 0.95-1.19), but ticagrelor was associated with an increase in non-CABG major bleeding (4.8 vs. 3.8%; HR 1.28; 95% CI = 1.05-1.56).”
Panel auditInternal validity: medium · scope of inference: NSTE-ACS patients in PLATO, ticagrelor versus clopidogrel, with and without revascularization.Key limitations: retrospective subgroup analysis · non-CABG major bleeding significantly higher despite similar total
3 of 17 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
A consistent directional and significant non-CABG bleeding increase supports the claim, but the pivotal trial's null total-major-bleeding endpoint caps confidence at the conservative end of Likely.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
Null total-major-bleeding endpoint in the pivotal trial. The claim speaks to major bleeding generally, yet total major bleeding was not significantly increased in the registrational trial (11.6 vs. 11.2%; P = 0.43) [15] or its renal subgroup [17]. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: An adequately powered randomised comparison in a general ACS population with total major bleeding as the pre-specified endpoint.
Open question: Does ticagrelor increase total major bleeding versus clopidogrel in a general, randomised ACS population, as opposed to the non-CABG subcategory? Why it is still open: The pivotal trial's total major bleeding endpoint was null (11.6 vs. 11.2%; P = 0.43) [15] and the renal subgroup was null (HR 1.07, 95% CI 0.88 to 1.30) [17], while only the subcategory was significant.
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 21 Oct 2026 · protocol v0.19