Sentence: The objective was to compare the pharmacodynamic ( PD ) and pharmacokinetic ( PK ) effects of ticagrelor with clopidogrel among subjects of Hispanic ethnicity , as the PD and PK effects of antiplatelet agents among Hispanics are not specifically known .
Drug combination annotation:
[{'class': 'COMB', 'spans': ['ticagrelor', 'clopidogrel'], 'is_context_needed': True}]