Prasugrel for Japanese patients with acute coronary syndrome in short-term clinical practice (PRASFIT-Practice I): a postmarketing observational study

Data on prasugrel use in Japanese patients are limited to phase II/III clinical trials. This early postmarketing observational study evaluated the safety and efficacy of short-term prasugrel use in patients with acute coronary syndrome (ACS) in real-world clinical settings in Japan. From May 2014 to January 2015, we enrolled consecutive patients with ACS requiring percutaneous coronary intervention in each institution. Each patient started prasugrel treatment ≥1 month before the end of the study period. Safety outcomes included incidence rates of adverse drug reactions (ADRs) and bleeding adverse events (AEs). Efficacy outcomes were incidence rates of cardiovascular events (including major adverse cardiovascular events [MACE]). Case report forms were collected from 749 patients, 732 of whom were eligible for the safety and efficacy analysis sets. Approximately 95% of patients had a prasugrel loading/maintenance dose of 20 mg/3.75 mg/day. The incidences of ADRs and bleeding AEs were 8.6 and 6.4%, respectively. Twelve patients experienced major bleeding AEs; approximately 60% (seven patients) of which were gastrointestinal disorders. The incidence of bleeding AEs was significantly higher primarily in patients of female sex, aged ≥75 years, with low body weight (≤50 kg), severe cardiovascular disease, or severe renal impairment. The incidence of MACE was 1.9% during prasugrel treatment, and 3.1% at the end of the study period. This short-term study indicated that prasugrel treatment at loading/maintenance doses of 20 mg/3.75 mg/day was safe and effective in Japanese ACS patients in an acute setting. Clinical Trial Registration: This study is registered at http://www.umin.ac.jp/ctr/ under the identifier UMIN000014699.