The pharmacokinetics and safety of a fixed-dose combination of acetylsalicylic acid and clopidogrel compared with the concurrent administration of acetylsalicylic acid and clopidogrel in healthy subjects: a randomized, open-label, 2-sequence, 2-period, single-dose crossover study

Background: Dual antiplatelet therapy with clopidogrel plus acetylsalicylic acid (ASA) is used for the treatment of acute coronary syndrome. A combined formulation of ASA and clopidogrel has been developed to provide dosing convenience and improve adherence.

Objective: This study was designed to compare the pharmacokinetic properties and safety profile of a fixed-dose combination formulation of ASA and clopidogrel with concurrent administration of each agent in healthy male Korean volunteers.

Methods: This single-dose, randomized, open-label, 2-period crossover study was conducted in 64 healthy Korean volunteers. Equal numbers of eligible participants were randomly assigned to receive either the fixed-dose combination of ASA 100 mg and clopidogrel 75 mg or the free combination of each agent followed by a 7-day washout period and then administration of the alternate formulation. Serial blood samples were collected immediately before and after dosing for 24 hours. The safety profile was evaluated by using adverse events (AEs), which were assessed by physical examination, vital signs, ECGs, clinical laboratory tests, and interviews. The 2 formulations were considered to be bioequivalent if the 90% CIs for the log-transformed C(max) and AUC(0-last) values were within the predetermined range of 0.8 to 1.25.

Results: Sixty-four volunteers (mean [SD] age, 27.51 [8.15] years; weight, 68.55 [7.86] kg; height, 173.80 [5.94] cm) were enrolled, and 63 completed the study. For ASA, the 90% CIs for the geometric mean ratios of C(max) and AUC(0-last) were 0.9483 to 1.1717 and 0.9946 to 1.1020, respectively. For salicylic acid, the 90% CIs were 0.9614 to 1.0396 for C(max) and 0.9778 to 1.0163 for AUC(0-last). For clopidogrel, the 90% CIs were 0.9809 to 1.2562 for C(max) and 0.9674 to 1.2073 for AUC(0-last). Six of the 20 AEs reported were drug related: decreased hemoglobin levels (n = 2), fever (n = 1), and headache (n = 1) with the test formulation and increased alanine aminotransferase levels (n = 1) and dyspepsia (n = 1) with the reference formulation. All of the drug-related AEs were transient and mild in severity.

Conclusions: The fixed-dose combination of ASA and clopidogrel 100 mg/75 mg did not meet the regulatory criteria for bioequivalence as defined by the Korea Food and Drug Administration. Both formulations were well tolerated in these healthy male Korean subjects. ClinicalTrials.gov Identifier: NCT01448330.