Low Dose Ticagrelor Versus Low Dose Prasugrel in Patients With Prior Myocardial Infarction

Taken together the results from DAPT and PEGASUS-TIMI54, it appears that physicians may consider extending beyond 1 year or reinitiating treatment with a thienopyridine or ticagrelor 60mg bid in patients with a prior MI and features of high ischemic and low bleeding risk. Comparative clinical or pharmacodynamic studies, however, between prasugrel 5 mg od and ticagrelor 60 mg bid in the chronic phase of stable post MI patients have not been performed. In light of this, we believe that a dedicated pharmacodynamic study of ticagrelor 60 bid mg vs prasugrel 5 mg od in a PEGASUS-like population would be informative for the practicing clinician, thus setting the rationale for conducting this specifically designed investigation.

This is a prospective, randomized, single blind, single center, crossover study. Eligible patients undergoing P2Y12 receptor antagonist therapy before screening will undergo a 14-day minimum washout period before randomization. Following screening/washout period (visit 1), patients will be randomized (visit 2, time 0) in 1:1 fashion to either prasugrel 5 mg od or ticagrelor 60 mg bid. Following 14±2 days (visit 3) patients will receive alternate treatment for additional 14 days (visit 4). Platelet reactivity assessment will be performed with the VerifyNow P2Y12 reaction assay at time 0, prior to first study drug dose. At visit 3 platelet function will be assessed at 2-4 hours post dose and prior to crossover. At visit 4 also platelet function will be assessed at 2-4 hours post study drug post dose. All patients will receive concomitant aspirin (100 mg/d) and standard secondary prevention medication. The primary endpoint is the platelet reactivity measured in P2Y12 reaction units (PRU) at the end of the 2 study periods (pre-crossover and post-crossover).