We previously analyzed five trials on ticagrelor/aspirin versus clopidogrel/aspirin in patients with minor stroke/ TIA in a network meta-analysis. We updated our search and identified 311 new citations with one study for inclusion: CHANCE2 enrolled patients with CYP2C19 loss-of-function alleles and randomized them to ticagrelor/aspirin or clopidogrel/aspirin. Pooling of CHANCE2 with the original studies could not be completed due to violation of NMA assumptions, due to significant inconsistency. This suggests patients with CYP2C19 loss-of-function alleles represent a subpopulation that is inherently different from the general stroke population in their antiplatelet response. Results from CHANCE-2 may not be generalizable without genotype testing.
Keywords: antiplatelet therapy; aspirin; clopidogrel; stroke; ticagrelor; transient ischemic attack (TIA).