Real-world in-hospital antiplatelet-switching strategy after coronary interventions: The Switch study

Key takeaway

Real-life strategy of using ticagrelor or prasugrel for fast and reliable periprocedural antiplatelet inhibition followed by acute switch to long-term clopidogrel therapy was safe and efficacious.

• The acute switching strategy (before hospital discharge) appeared safe from a bleeding, reinfarction, stent thrombosis, and 30-day mortality perspective.

• The balance between efficacy and safety of ticagrelor and prasugrel vs effect of increased adherence to lower-cost clopidogrel therapy warrants further consideration.

Why this matters

• Non-affordability due to higher cost of newer antiplatelet agents may lead to compliance concerns.
• There is a paucity of data on acute antiplatelet agent switching in the real-world clinical setting.

Study design

• Large, retrospective, single-center study (N = 5,007)*
• Key inclusion criteria Patients who underwent a PCI between January 1, 2013 and December 31, 2016
• Key exclusion criteria Patients who were prescribed ticlopidine (n = 18)
• Loading and maintenance antiplatelet agent: Patients were divided into 5 subgroups^†
• Endpoints: 30-day all-cause mortality and bleeding events^‡

Key results

• Overall, 5,007 patients were included in the analysis
  Prior to PCI: 54.8% of patients were preloaded with ticagrelor,
  8.5% with prasugrel, and 36.7% with clopidogrel
• Switch to long-term clopidogrel therapy:
  • 93% patients initially loaded with ticagrelor
  • 58% patients initially loaded with prasugrel
• Bleeding events:
  • Significant differences in major bleeding (depending on antiplatelet management strategy; P <0.001)
  • Lowest bleeding rates:
    In patients pretreated with ticagrelor or prasugrel and switched to clopidogrel
    (0.9% and 0.8%, respectively)
  • Highest rates of major BARC 3a bleeding: In patients maintained on ticagrelor or clopidogrel (2.52% and
    1.74%, respectively)^§
• 30-day all-cause mortality:
  • 30-day all-cause mortality rate: 1%
  • 30-day all-cause mortality: Significantly lower in patients who underwent switching strategy vs those on clopidogrel therapy throughout hospitalization (P <0.001)
  • Highest all-cause mortality rates: In patients maintained on clopidogrel throughout index hospitalization (1.9%), followed by patients loaded with ticagrelor and then switched to clopidogrel (0.6%)

Limitations

• Single-center, retrospective study with limited 30-day outcome data
• Baseline patient characteristics were not presented (these may have differed across treatment arms)
• Rationale for selection and switching between P2Y12 inhibitors was at the treating physician’s discretion and not recorded
• Retrospective data abstraction from charts (UMass EMR)

* N = 5,007; University of Massachusetts Memorial Medical Center.

† Patients were divided into 5 subgroups based on choice of loading and maintenance antiplatelet agent: ticagrelor to ticagrelor; ticagrelor to clopidogrel; prasugrel to prasugrel; prasugrel to clopidogrel; and clopidogrel to clopidogrel.

‡ 30-day all-cause mortality and bleeding events as defined by BARC.

§ After accounting for additional periprocedural use of intravenous GP IIb/ IIIa inhibitors, patients loaded with ticagrelor and switched to clopidogrel had the lowest BARC 3a bleeding rates (0.75%) and patients maintained throughout on ticagrelor had the highest bleeding (1.96%).