PRASFIT-ACS: important evidence against a "one-guideline-fits-all-races" approach to antiplatelet therapy.

was more prominent in subjects with body weight <60 kg (45– 56% higher).7 This pharmacokinetic characteristic in East Asians vs. Caucasians corresponds with the pharmacodynamic profile. In a healthy volunteer study,7 the level of platelet inhibition during 5 mg/day prasugrel in East Asians was similar to that during 10 mg/day prasugrel in Caucasians (68.9% vs. 70.1% at 4 h last-dose). In PCI-treated Japanese, 2.5 mg/day prasugrel and 75 mg/day clopidogrel achieved similar antiplatelet effects (Caucasians: 4.5 mg/day prasugrel ≈75 mg/day clopidogrel). Taken together, the unique characteristics of East Asians in thrombogenicity and pharmacokinetic/pharmacodynamic profile of P2Y12 inhibitors may have influenced the results of PRASFITACS. Although the size of East Asia is the greatest in the world (>1.5 billion people), few East Asians have been included in the major randomized clinical trials assessing the benefit of newer P2Y12 inhibitors. Simple adoption of Western guidelines and recommendations, mostly based on clinical data derived from Western populations, may not be appropriate for East Asians. Excessive inhibition of platelet function by new P2Y12 inhibitors in East Asians may markedly increase the risk of serious bleeding without further protection against thrombotic events. Therefore, dedicated studies for East Asians are required before we can readily apply established novel antithrombotic regimens used for Western populations. In this line, PRASFIT-ACS is a big step toward the concept of “race-based antithrombotic therapy”.