Reviews/P2Y12 Antiplatelets/Cangrelor reduces stent thrombosis vs clopidogrel loading during PCI
Cangrelor · P2Y12-CANG-01 · v1
One large, blinded, randomised trial directly compared intravenous cangrelor against a standard oral clopidogrel loading dose in patients having stents placed, and it found fewer stent clots in the cangrelor group within two days [1]. A separate analysis of men and women from that same trial pointed the same way [18]. The catch is that almost all of the supporting evidence comes from a single research programme funded by one sponsor, so there is no independent trial confirming the result. A second direct head-to-head trial against clopidogrel loading did not show an overall advantage for cangrelor [12]. The panel therefore treated the finding as real but not yet firmly settled, because it leans so heavily on one body of work and a companion trial did not agree on its main measure.
The exact comparison is tested head-to-head by one pivotal double-blind RCT [1], where stent thrombosis at 48 hours fell from 1.4% with clopidogrel loading to 0.8% with cangrelor (odds ratio 0.62, P=0.01). The prespecified sex subgroup of that same trial reproduced the direction, reducing stent thrombosis by 61% in women and 16% in men [18]. Pooled patient-level and core-lab analyses from the same CHAMPION programme are consistent on the broader ischaemic composite [10][13]. A placebo-controlled trial separately lowered stent thrombosis from 0.6% to 0.2% [2], but its comparator is placebo, not clopidogrel loading. The registry and matched-pair reports [8][14] are non-randomised and carry no clopidogrel-loading comparator. The contested point: The division is whether a single significant stent-thrombosis result, obtained as a secondary endpoint within one sponsored programme [1][18], is enough on its own. The other direct head-to-head against clopidogrel loading [12] was not superior on its primary composite (7.5% vs 7.1%, P=0.59), so the direct randomised evidence is not internally uniform.
All 20 papers behind this claim with their DOIs and what each does to it, the panel’s arbitration, the evidence gap map and the open research questions. Free, and sent to your inbox.
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The positive stent-thrombosis signal is concentrated in a single sponsored programme — CHAMPION PHOENIX [1] and its own subanalyses [10][13][18] are largely the same patients and sponsor — with no independent replication of the comparative result.
The other direct head-to-head against clopidogrel loading, CHAMPION PCI [12], was not superior on its primary composite and reports no stent-thrombosis benefit, making the direct vs-clopidogrel-loading evidence internally inconsistent.
Where it remains uncertain. The result rests on a secondary endpoint within one sponsored programme [1], and the companion direct trial against clopidogrel loading was not superior on its primary composite (7.5% vs 7.1%, P=0.59) [12].
Aleatory
Stent thrombosis is infrequent (0.8% vs 1.4% in [1]), so even in a large trial the effect is estimated from relatively few events, widening the plausible range.
The load-bearing papers from a corpus of 20, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Primary direct randomised evidence: a significant reduction in stent thrombosis vs clopidogrel loading during PCI — matches the claim exactly
Panel auditInternal validity: high · scope of inference: Patients undergoing urgent or elective PCI, cangrelor vs clopidogrel loading, 48-h stent thrombosis.Key limitations: 48-h endpoint only · secondary endpoint · transient dyspnoea higher with cangrelor
The other direct head-to-head vs clopidogrel loading, neutral on its primary endpoint — tempers the strength of the comparative claim
“At 48 hours, cangrelor was not superior to clopidogrel with respect to the primary composite end point, which occurred in 7.5% of patients in the cangrelor group and 7.1% of patients in the clopidogrel group (odds ratio, 1.05; 95% confidence interval [CI], 0.88 to 1.24; P=0.59).”
Panel auditInternal validity: high · scope of inference: ACS patients undergoing PCI, cangrelor vs clopidogrel loading, 48-h composite.Key limitations: stent thrombosis not reported · primary endpoint not superior · higher ACUITY major bleeding with cangrelor
Prespecified subgroup of the pivotal trial confirming the direction of the stent-thrombosis reduction across sexes
“Cangrelor reduced the odds of stent thrombosis by 61% in women (OR, 0.39; 95% CI, 0.20-0.77) and 16% in men (OR, 0.84; 95% CI, 0.53-1.33; P interaction=0.11).”
Panel auditInternal validity: high · scope of inference: CHAMPION PHOENIX PCI patients, stent thrombosis by sex.Key limitations: subgroup analysis · men's estimate not significant · moderate bleeding increased in women
The stent thrombosis reduction (0.6% to 0.2%) is cangrelor vs placebo, not vs a clopidogrel loading dose, so it does not speak to the claim's contrast.
Panel auditInternal validity: high · scope of inference: Clopidogrel-naive PCI patients, cangrelor vs placebo add-on.Key limitations: comparator is placebo not clopidogrel loading · enrolment stopped early · more groin haematomas with cangrelor
4 of 20 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.
The exact comparison is directly supported by one pivotal RCT on a prespecified stent-thrombosis endpoint, but low evidential independence and a neutral companion trial prevent a higher tier.
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.
Independent replication of the comparative stent-thrombosis result. The entire positive comparative signal sits within one sponsored programme [1][10][13][18]; nothing in the corpus confirms it independently. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: A new double-blind RCT of cangrelor versus clopidogrel loading during PCI, differently sponsored, with stent thrombosis as a prespecified primary or key secondary endpoint.
Open question: Does cangrelor's reduction in stent thrombosis versus clopidogrel loading replicate outside the CHAMPION programme? Why it is still open: Every supporting comparative result in the corpus derives from the same programme and sponsor [1][10][13][18], with no independent trial.
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 21 Oct 2026 · protocol v0.19