Aspirin and Clopidogrel Resistance Study

Sponsor

University Hospital, Basel, Switzerland (Other)

Overall Status

Completed

CT.gov ID

NCT01039480

Collaborator

(none)

Enrollment

Location

Duration (Months)

4.8

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Resistance to antiplatelet drugs (aspirin, clopidogrel) is a recognized phenomenon with a prevalence from 17% to 35%. Resistance as detected by in vitro tests such as Multiple Electrode Aggregometry (MEA) has been shown to predict clinical therapy failure. Resistance can be caused by clinical, cellular and pharmacogenetic factors. Non compliance is suspected to be an important contributing factor. In this study, compliance will be assured with an electronical compliance monitoring system. Factors to non response will be identified to find plausible explanations when in vitro platelet aggregation inhibition is insufficient despite assured compliance. This study will help to disclose the relationship between compliance, biomarker and clinical outcome as well as to quantify the impact of non compliance to the resistance phenomenon as measured by MEA.

Condition or Disease	Intervention/Treatment	Phase
Drug Resistance

Study Design

Study Type:

Observational

Actual Enrollment :

82 participants

Observational Model:

Cohort

Time Perspective:

Cross-Sectional

Official Title:

Aspirin- and Clopidogrel-Resistance: Non-compliance and Other Contributing Factors

Study Start Date :

May 1, 2010

Actual Primary Completion Date :

Jun 1, 2011

Actual Study Completion Date :

Oct 1, 2011

Arms and Interventions

Arm	Intervention/Treatment
dual therapy (ASS/CLO) patients with a prescription for dual antiplatelet therapy with aspirin AND clopidogrel
clopidogrel users (CLO) patients with a prescription for clopidogrel
aspirin users (ASP) patients with a prescription for aspirin

Outcome Measures

Primary Outcome Measures

Platelet aggregation, initial and after one week under compliance monitoring. [1 week]

Secondary Outcome Measures

Data on compliance (measured by electronic compliance monitoring, Morisky MMAS-8 and BMQ Score) [1 week]
Frequency of contributing factors to non-response in responders compared to non-responders (pharmacogenetics, clinical factors and drug-drug interactions) [4 weeks]

Eligibility Criteria

Criteria

Ages Eligible for Study:

45 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Patients prescribed aspirin and/or clopidogrel for both including both cardiovascular and cerebrovascular indications seeing their general practitioner in or nearby Olten/SO for any medical purpose
Patients with oral and written German language ability

Exclusion Criteria:

Patients living in care homes
Patients not preparing their drugs on their own (e.g. outpatient medical assistance through "spitex").
Patients with acute cardiac symptoms

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Study Centre at Aarelab AG, Olten	Olten	Solothurn	Switzerland	4600

Sponsors and Collaborators

University Hospital, Basel, Switzerland

Investigators

Study Chair: Kurt E Hersberger, PhD, Pharmaceutical Care Research Group, Departement of Pharmacy, University Basel
Principal Investigator: Michel Romanens, MD, Kardiologische Praxis, Olten/SO
Study Director: Dimitrios Tsakiris, MD, Hemostaseology Lab, University Hospital Basel
Principal Investigator: Philipp N Walter, MSc, Pharmaceutical Care Research Group, Department of Pharmacy, University of Basel