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| Name | Class |
|---|---|
| AstraZeneca | INDUSTRY |
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Recent studies have shown that withdrawing aspirin and maintaining P2Y12 inhibitor monotherapy for up to 12 months post-PCI, after a brief period of DAPT, reduces bleeding without increasing ischemic harm. Such effects have shown to of particular benefit in patients with diabetes mellitus (DM). However, if an aspirin-free approach can be considered after this time frame is a matter of debate. The aim of this study is to assess the PD effects of ticagrelor 60 mg with and without aspirin therapy in CAD patients and to compare this with a standard DAPT regimen of aspirin plus clopidogrel.
Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is the standard of care for the prevention of thrombotic complications in patients with coronary artery disease (CAD) undergoing percutaneous coronary interventions (PCI). However, such ischemic benefit occurs at the expense of enhanced bleeding, the risk of which increases in a graded fashion with prolonged exposure to DAPT. Recent studies have shown that withdrawing aspirin and maintaining P2Y12 inhibitor monotherapy for up to 12 months post-PCI, after a brief period of DAPT, reduces bleeding without increasing ischemic harm. Such effects have shown to of particular benefit in patients with diabetes mellitus (DM). However, if an aspirin-free approach can be considered after this time frame is a matter of debate. In fact, current guidelines recommend maintaining P2Y12 inhibiting therapy for high risk patients but which all imply background use of aspirin. P2Y12 inhibitors for long-term (beyond 12 months) secondary prevention mainly include clopidogrel and ticagrelor. In particular, the dosing regimen for clopidogrel remains the standard 75 mg qd, whereas ticagrelor dosing is recommended to be reduced from 90 mg bid to 60 mg bid. However, of these regimens the pharmacodynamics (PD) effects of ticagrelor 60 mg in the absence of aspirin has not yet been tested. Because DM patients are likely to continue with long-term P2Y12 inhibitor therapy, defining the optimal antithrombotic approach for these patients is of critical importance. In light of the above made observations, patients with DM represent an ideal population to define the antiplatelet effects of a ticagrelor 60 mg monotherapy regimen. The aim of this study is to assess the PD effects of ticagrelor 60 mg with and without aspirin therapy in CAD patients and to compare this with a standard DAPT regimen of aspirin plus clopidogrel.
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| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Ticagrelor | Experimental | ticagrelor 60 mg bid monotherapy |
|
| Aspirin plus Clopidogrel | Active Comparator | aspirin 81 mg qd plus clopidogrel 75 mg qd |
|
| Aspirin plus Ticagrelor | Active Comparator | aspirin 81 mg qd plus ticagrelor 60 mg bid |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Ticagrelor monotherapy | Drug | Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| Measure | Description | Time Frame |
|---|---|---|
| P2Y12 Reaction Units (PRU) | The primary end-point of the study is the comparison of the PRU determined by VerifyNow PRU between between aspirin plus ticagrelor 60 mg and ticagrelor 60 mg monotherapy (trough effect pre-dosing). The VerifyNow System is a turbidimetric based optical detection system which measures platelet induced aggregation as an increase in light transmittance. The assay is based on microbead agglutination induced by adenosine diphosphate (ADP). The instrument measures this change in optical signal and reports results in P2Y12 Reaction Units (PRU). | Day 10, pre-dose |
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| Measure | Description | Time Frame |
|---|---|---|
| VASP | Comparison of the platelet reactivity index (PRI) determined by VASP between between aspirin plus ticagrelor 60 mg and ticagrelor 60 mg monotherapy. VASP phosphorylation (VASP-P) is a marker of P2Y12 receptor signaling. VASP was assessed the ELISA VASP-P kit. Low PRI indicates appropriate platelet inhibition. | Day 10, pre-dose |
Inclusion criteria:
For inclusion in the study patients should fulfill the following criteria:
Exclusion criteria:
PCI < 6 months prior
Recent (< 6 months) type I myocardial infarction
Anticipated concomitant oral or intravenous therapy with strong cytochrome P450 3A4 (CYP3A4) inhibitors or CYP3A4 substrates with narrow therapeutic indices that cannot be stopped for the course of the study:
Anticipated concomitant oral or intravenous therapry of strong CYP3A inducers (phenytoin, rifampin, phenobarb, carbamazepine)
Need for chronic oral anticoagulant therapy or chronic low-molecular-weight heparin (at venous thrombosis treatment not prophylaxis doses)
Patients with known bleeding diathesis or coagulation disorder
History of previous intracerebral bleed at any time, gastrointestinal (GI) bleed within the past 6 months prior to randomization, or major surgery within 30 days prior to randomization
Active pathological bleeding
Hypersensitivity to aspirin, ticagrelor or clopidogrel
Increased risk of bradycardic events (eg, known sick sinus syndrome, second or third degree AV block or previous documented syncope suspected to be due to bradycardia) unless treated with a pacemaker
Known severe liver disease
Renal failure requiring dialysis
Known platelet count <80x106/mL
Known hemoglobin <9 g/dL
Pregnant or breastfeeding women. *Women of childbearing age must use reliable birth control (i.e. oral contraceptives) while participating in the study.
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| Name | Affiliation | Role |
|---|---|---|
| Dominick J Angiolillo, MD,PhD | University of Florida | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| University of Florida | Jacksonville | Florida | 32209 | United States |
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105 patients consented.
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| ID | Title | Description |
|---|---|---|
| FG000 | Ticagrelor | ticagrelor 60 mg bid monotherapy Ticagrelor monotherapy: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| FG001 | Aspirin Plus Clopidogrel | aspirin 81 mg qd plus clopidogrel 75 mg qd Clopidogrel with aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| FG002 | Aspirin Plus Ticagrelor | aspirin 81 mg qd plus ticagrelor 60 mg bid Ticagrelor plus aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| FG003 | Aspirin Plus Ticagrelor 90 mg | Eligible patients entered a 7-10 day run-in phase with aspirin 81 mg qd plus ticagrelor 90 mg bid |
| FG004 | Ticagrelor 90 mg Monotherapy | Patients discontinued aspirin and maintained ticagrelor 90 mg bid monotherapy for 10±3 days. |
| Title | Milestones | Reasons Not Completed | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Run-in Phase With Aspirin and Ticagrelor |
|
| ||||||||||||||||||
| Run-in Phase With Ticagrelor Monotherapy |
| |||||||||||||||||||
| Randomized Treatment |
|
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| ID | Title | Description |
|---|---|---|
| BG000 | Ticagrelor | ticagrelor 60 mg bid monotherapy Ticagrelor monotherapy: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| Units | Counts |
|---|---|
| Participants |
|
| Title | Description | Population Description | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Denominator Units Selected | Denominators | Classes |
|---|---|---|---|---|---|---|---|---|---|
| Age, Continuous | Mean |
| Type | Title | Description | Population Description | Reporting Status | Anticipated Posting Date | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Time Frame | Units Analyzed | Denominator Units Selected | Arm/Group Information | Denominators | Classes | Analyses | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Primary | P2Y12 Reaction Units (PRU) | The primary end-point of the study is the comparison of the PRU determined by VerifyNow PRU between between aspirin plus ticagrelor 60 mg and ticagrelor 60 mg monotherapy (trough effect pre-dosing). The VerifyNow System is a turbidimetric based optical detection system which measures platelet induced aggregation as an increase in light transmittance. The assay is based on microbead agglutination induced by adenosine diphosphate (ADP). The instrument measures this change in optical signal and reports results in P2Y12 Reaction Units (PRU). | Posted | Mean | 95% Confidence Interval | PRU | Day 10, pre-dose |
|
10 days
These adverse event reporting reflects adverse events occurred during the randomized phase of the study.
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| ID | Title | Description | Deaths (Affected) | Deaths (At Risk) | Serious Events (Affected) | Serious Events (At Risk) | Other Events (Affected) | Other Events (At Risk) |
|---|---|---|---|---|---|---|---|---|
| EG000 | Ticagrelor | ticagrelor 60 mg bid monotherapy Ticagrelor monotherapy: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| Term | Organ System | Source Vocabulary | Assessment Type | Notes | Statistical Information |
|---|---|---|---|---|---|
| iliac artery perforation | Surgical and medical procedures | Systematic Assessment | Common iliac artery perforation and intra-abdominal bleeding occurred during a procedure that was performed per standard of care |
| Term | Organ System | Source Vocabulary | Assessment Type | Notes | Statistical Information |
|---|---|---|---|---|---|
| dyspnea | Respiratory, thoracic and mediastinal disorders | Systematic Assessment |
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| Title | Organization | Phone | Extension | |
|---|---|---|---|---|
| Francesco Franchi, MD | University of Florida College of Medicine Jacksonville | 904-244-5515 | francesco.franchi@jax.ufl.edu |
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| Type | Includes Protocol | Includes SAP | Includes ICF | Document Label | Document Date | Document Uploaded Date | Document File Name |
|---|---|---|---|---|---|---|---|
| Prot_SAP | Yes | Yes | No | Study Protocol and Statistical Analysis Plan | Oct 27, 2022 | Feb 6, 2025 | Prot_SAP_000.pdf |
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| ID | Term |
|---|---|
| D003924 | Diabetes Mellitus, Type 2 |
| D003324 | Coronary Artery Disease |
| D003920 | Diabetes Mellitus |
| ID | Term |
|---|---|
| D044882 | Glucose Metabolism Disorders |
| D008659 | Metabolic Diseases |
| D009750 | Nutritional and Metabolic Diseases |
| D004700 | Endocrine System Diseases |
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| ID | Term |
|---|---|
| D000077486 | Ticagrelor |
| D001241 | Aspirin |
| D000077144 | Clopidogrel |
| ID | Term |
|---|---|
| D000241 | Adenosine |
| D011684 | Purine Nucleosides |
| D011687 | Purines |
| D006574 | Heterocyclic Compounds, 2-Ring |
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Prospective randomized
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Staff performing PK/PD assessments will remain blinded to treatment assignment.
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|
|
| Ticagrelor plus aspirin | Drug | Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
|
|
| Clopidogrel with aspirin | Drug | Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
|
|
| Comparison of Platelet Aggregation With ADP as Stimuli Determined by Light Transmittance Aggregometry Between Between Aspirin Plus Ticagrelor 60 mg and Ticagrelor 60 mg Monotherapy. |
Platelet aggregation was stimulated by ADP. Platelet aggregation will be determined as the maximal percent change (MPA%) in light transmittance from baseline. Low MPA% reflects good platelet inhibition. |
| Day 10, pre-dose |
| Comparison of Thrombus Formation Measured by T-TAS Between Between Aspirin Plus Ticagrelor 60 mg and Ticagrelor 60 mg Monotherapy | T-TAS is an automated microchip flow chamber system for the quantitative analysis of the thrombus formation process under blood flow conditions. In the present study, total platelet-derived thrombus formation is expressed as the area under the flow pressure curve for the first 10 min for the PL-chip tested at a flow rate of 18 μL/min (PL18-AUC10). Results of the assay are reported as PL18-AUC10. Low AUC reflect reduced thrombus growth and rapid breakdown of the thrombus. | Day 10, pre-dose |
| Withdrawal by Subject |
|
| Physician Decision |
|
| Lost to Follow-up |
|
| COMPLETED |
|
| NOT COMPLETED |
|
|
| COMPLETED |
|
| NOT COMPLETED |
|
|
| BG001 | Aspirin Plus Clopidogrel | aspirin 81 mg qd plus clopidogrel 75 mg qd Clopidogrel with aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| BG002 | Aspirin Plus Ticagrelor | aspirin 81 mg qd plus ticagrelor 60 mg bid Ticagrelor plus aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| BG003 | Total | Total of all reporting groups |
| years |
|
| Sex: Female, Male | Count of Participants | Participants |
|
| Race (NIH/OMB) | Count of Participants | Participants |
|
| Hemoglobin A1c | Mean | Standard Deviation | % of glycated hemoglobin |
|
| OG001 | Aspirin Plus Clopidogrel | aspirin 81 mg qd plus clopidogrel 75 mg qd Clopidogrel with aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
| OG002 | Aspirin Plus Ticagrelor | aspirin 81 mg qd plus ticagrelor 60 mg bid Ticagrelor plus aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. |
|
|
|
| Other Pre-specified | VASP | Comparison of the platelet reactivity index (PRI) determined by VASP between between aspirin plus ticagrelor 60 mg and ticagrelor 60 mg monotherapy. VASP phosphorylation (VASP-P) is a marker of P2Y12 receptor signaling. VASP was assessed the ELISA VASP-P kit. Low PRI indicates appropriate platelet inhibition. | Posted | Mean | 95% Confidence Interval | PRI | Day 10, pre-dose |
|
|
|
| Other Pre-specified | Comparison of Platelet Aggregation With ADP as Stimuli Determined by Light Transmittance Aggregometry Between Between Aspirin Plus Ticagrelor 60 mg and Ticagrelor 60 mg Monotherapy. | Platelet aggregation was stimulated by ADP. Platelet aggregation will be determined as the maximal percent change (MPA%) in light transmittance from baseline. Low MPA% reflects good platelet inhibition. | Posted | Mean | 95% Confidence Interval | MPA% | Day 10, pre-dose |
|
|
|
| Other Pre-specified | Comparison of Thrombus Formation Measured by T-TAS Between Between Aspirin Plus Ticagrelor 60 mg and Ticagrelor 60 mg Monotherapy | T-TAS is an automated microchip flow chamber system for the quantitative analysis of the thrombus formation process under blood flow conditions. In the present study, total platelet-derived thrombus formation is expressed as the area under the flow pressure curve for the first 10 min for the PL-chip tested at a flow rate of 18 μL/min (PL18-AUC10). Results of the assay are reported as PL18-AUC10. Low AUC reflect reduced thrombus growth and rapid breakdown of the thrombus. | Posted | Mean | 95% Confidence Interval | kPa x minutes | Day 10, pre-dose |
|
|
|
| 0 |
| 26 |
| 0 |
| 26 |
| 7 |
| 26 |
| EG001 | Aspirin Plus Clopidogrel | aspirin 81 mg qd plus clopidogrel 75 mg qd Clopidogrel with aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. | 0 | 27 | 0 | 27 | 12 | 27 |
| EG002 | Aspirin Plus Ticagrelor | aspirin 81 mg qd plus ticagrelor 60 mg bid Ticagrelor plus aspirin: Eligible patients will enter a 7-10 day run-in phase with aspirin 81 mg/ qd plus ticagrelor 90 mg bid after which they will discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days. After this period, patients will be randomized using a randomly generated computer sequence in a 1:1:1 fashion to either: a) ticagrelor 60 mg bid monotherapy; b) aspirin 81 mg qd plus ticagrelor 60 mg bid; c) aspirin 81 mg qd plus clopidogrel 75 mg qd. Randomized treatment will be maintained for 10±3 days. | 0 | 28 | 0 | 28 | 7 | 28 |
| EG003 | Aspirin Plus Ticagrelor 90 mg | 7-10 day run-in phase with aspirin 81 mg qd plus ticagrelor 90 mg bid | 0 | 101 | 2 | 101 | 7 | 101 |
| EG004 | Ticagrelor 90 mg Monotherapy | discontinue aspirin and maintain ticagrelor 90 mg bid monotherapy for 10±3 days | 0 | 82 | 0 | 82 | 0 | 82 |
|
| chest pain | Cardiac disorders | Systematic Assessment |
|
Not provided
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| D003327 | Coronary Disease |
| D017202 | Myocardial Ischemia |
| D006331 | Heart Diseases |
| D002318 | Cardiovascular Diseases |
| D001161 | Arteriosclerosis |
| D001157 | Arterial Occlusive Diseases |
| D014652 | Vascular Diseases |
| D000072471 |
| Heterocyclic Compounds, Fused-Ring |
| D006571 | Heterocyclic Compounds |
| D009705 | Nucleosides |
| D009706 | Nucleic Acids, Nucleotides, and Nucleosides |
| D012263 | Ribonucleosides |
| D012459 | Salicylates |
| D062385 | Hydroxybenzoates |
| D010636 | Phenols |
| D001555 | Benzene Derivatives |
| D006841 | Hydrocarbons, Aromatic |
| D006844 | Hydrocarbons, Cyclic |
| D006838 | Hydrocarbons |
| D009930 | Organic Chemicals |
| D013988 | Ticlopidine |
| D058924 | Thienopyridines |
| D013876 | Thiophenes |
| D013457 | Sulfur Compounds |
| D011725 | Pyridines |
| D006573 | Heterocyclic Compounds, 1-Ring |