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Vorapaxar in Patients With Prior Myocardial Infarction Treated With Prasugrel and Ticagrelor

Adjunctive Vorapaxar Therapy in Patients With Prior Myocardial Infarction Treated With New Generation P2Y12 Receptor Inhibitors Prasugrel and Ticagrelor (VORA-PRATIC): A Prospective, Randomized, Pharmacodynamic Study

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02545933
Acronym
VORA-PRATIC
Enrollment
130
Registered
2015-09-10
Start date
2016-02-29
Completion date
2020-01-31
Last updated
2020-09-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Myocardial Infarction

Keywords

prasugrel, ticagrelor, vorapaxar

Brief summary

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor represents the standard of care for the long-term secondary prevention of atherothrombotic events in patients with myocardial infarction (MI). However, rates of ischemic recurrences remain high, which may be in part due to the fact that other platelet signaling pathways, such as thrombin-induced platelet aggregation, continue to be activated. Vorapaxar is a protease-activated receptor (PAR)-1 inhibitor, which exerts potent inhibition of thrombin-mediated platelet aggregation. It is approved for clinical use by the Food and Drug Administration for the reduction of thrombotic cardiovascular events in patients with a history of MI or with peripheral arterial disease. However, to date clinical trial experience with vorapaxar has been almost exclusively with the P2Y12 receptor inhibitor clopidogrel and the effects of vorapaxar in combination with antiplatelet therapy including prasugrel or ticagrelor, is largely unexplored. Further, the role of vorapaxar as part of a dual antithrombotic treatment regimen, in addition to a novel P2Y12 receptor inhibitor, with withdrawal of aspirin, represents another important area of clinical interest as it has the potential to maximize ischemic protection while reducing the risk of bleeding. The proposed prospective, randomized, parallel-design, open label, study conducted in a real world clinical setting of post-MI patients will aim to assess the pharmacodynamic effects of vorapaxar in addition to antiplatelet therapy with a novel P2Y12 receptor inhibitor (prasugrel or ticagrelor) with and without aspirin.

Detailed description

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor represents the standard of care for the long-term secondary prevention of atherothrombotic events in patients with myocardial infarction (MI). The novel P2Y12 receptor inhibitors prasugrel and ticagrelor are characterized by more prompt, potent, and predictable antiplatelet effects compared with clopidogrel and are associated with a greater reduction of ischemic events in acute coronary syndrome patients. However, rates of ischemic recurrences remain high, which may be in part due to the fact that other platelet signaling pathways, such as thrombin-induced platelet aggregation, continue to be activated. Vorapaxar is a novel, orally active, competitive and slowly reversible protease-activated receptor (PAR)-1 inhibitor, which exerts potent inhibition of thrombin-mediated platelet aggregation. It is approved for clinical use by the Food and Drug Administration for the reduction of thrombotic cardiovascular events in patients with a history of MI or with peripheral arterial disease. A large-scale clinical trial showed that the use of vorapaxar (2.5 mg once/daily) in addition to standard antiplatelet therapy (including aspirin and a P2Y12 receptor inhibitor) was effective in the secondary prevention of recurrent thrombotic events in patients with previous atherothrombosis, in particular in patients with prior MI, at the expense of an increase in major bleeding. However, to date clinical trial experience with vorapaxar has been almost exclusively with the P2Y12 receptor inhibitor clopidogrel and the effects of vorapaxar in combination with state-of-the-art antiplatelet therapy in the post-MI setting, including prasugrel or ticagrelor, is largely unexplored. This may indeed represent a limitation for the uptake of vorapaxar in modern day clinical practice where these agents are being more broadly utilized. Further, the role of vorapaxar as part of a dual antithrombotic treatment regimen, in addition to a novel P2Y12 receptor inhibitor, with withdrawal of aspirin, represents another important area of clinical interest as it has the potential to maximize ischemic protection while reducing the risk of bleeding. The proposed prospective, randomized, parallel-design, open label, study conducted in a real world clinical setting of post-MI patients will aim to assess the pharmacodynamic effects of vorapaxar in addition to antiplatelet therapy with a novel P2Y12 receptor inhibitor (prasugrel or ticagrelor) with and without aspirin. Pharmacodynamic assessments will be performed at multiple time points and with different assays exploring multiple pathways of platelet aggregation. Exploratory assessments on the safety of such approach will also be evaluated.

Interventions

DRUGPrasugrel

Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily)

Vorapaxar will be administered at the dose of 2.5mg once daily

DRUGAspirin

Aspirin will be administered at the dose of 81mg once daily

DRUGTicagrelor

Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily)

Sponsors

Merck Sharp & Dohme LLC
CollaboratorINDUSTRY
University of Florida
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

1. Patients with a prior MI within the previous 2 weeks to 12 months. 2. On DAPT with low-dose aspirin (81mg od) and either prasugrel (10mg od) or ticagrelor (90mg bid) as per standard-of-care for at least 2 weeks. 3. Free from bleeding and ischemic events after the index MI event. 4. Age between 18 and 75 years old.

Exclusion criteria

1. History of stroke, transient ischemic attack, or intracranial hemorrhage. 2. Active pathological bleeding, history of bleeding events or increased risk of bleeding. 3. Known severe hepatic impairment. 4. Age \>75 years. 5. Body weight \<60 Kg. 6. Use of strong Cytochrome P450 3A inhibitors (e.g., ketoconazole, itraconazole, posaconazole, clarithromycin, nefazodone, ritonavir, saquinavir, nelfinavir, indinavir, boceprevir, telaprevir, telithromycin and conivaptan) or inducers (e.g., rifampin, carbamazepine, St. John's Wort and phenytoin). 7. On treatment with any oral anticoagulant (vitamin K antagonists, dabigatran, rivaroxaban, apixaban, edoxaban). 8. On treatment with any antiplatelet agent other than aspirin, prasugrel and ticagrelor in the past 14 days. 9. Creatinine clearance \<30 mL/minute. 10. Platelet count \<80x106/mL 11. Hemoglobin \<10g/dL 12. Hemodynamic instability 13. Pregnant females

Design outcomes

Primary

MeasureTime frameDescription
Maximal Platelet Aggregation30 daysThe primary end point of our study is the comparison of maximal platelet aggregation measured by light transmittance aggregometry using CAT (collagen-ADP-TRAP) between DAPT and DAPT plus vorapaxar after 30 days of treatment.

Countries

United States

Participant flow

Participants by arm

ArmCount
DAPT Plus Vorapaxar
Aspirin plus prasugrel or ticagrelor plus vorapaxar 2.5mg od Prasugrel: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily) Vorapaxar: Vorapaxar will be administered at the dose of 2.5mg once daily Aspirin: Aspirin will be administered at the dose of 81mg once daily Ticagrelor: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily)
44
Prasugrel/Ticagrelor Plus Vorapaxar
Prasugrel or ticagrelor plus vorapaxar 2.5mg od Prasugrel: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily) Vorapaxar: Vorapaxar will be administered at the dose of 2.5mg once daily Ticagrelor: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily)
43
DAPT
Aspirin in addition to prasugrel or ticagrelor Prasugrel: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily) Aspirin: Aspirin will be administered at the dose of 81mg once daily Ticagrelor: Patients will continue treatment with either prasugrel (10mg once daily) or ticagrelor (90mg twice/daily)
43
Total130

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyAdverse Event300
Overall StudyProtocol Violation101
Overall StudyWithdrawal by Subject233

Baseline characteristics

CharacteristicDAPT Plus VorapaxarPrasugrel/Ticagrelor Plus VorapaxarDAPTTotal
Age, Continuous57 years
STANDARD_DEVIATION 9
56 years
STANDARD_DEVIATION 9
56 years
STANDARD_DEVIATION 10
56 years
STANDARD_DEVIATION 10
Diabetes mellitus11 Participants12 Participants10 Participants33 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
17 Participants14 Participants13 Participants44 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
3 Participants3 Participants1 Participants7 Participants
Race (NIH/OMB)
White
24 Participants26 Participants29 Participants79 Participants
Region of Enrollment
United States
44 Participants43 Participants43 Participants130 Participants
Sex: Female, Male
Female
14 Participants11 Participants14 Participants39 Participants
Sex: Female, Male
Male
30 Participants32 Participants29 Participants91 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 440 / 430 / 43
other
Total, other adverse events
9 / 446 / 434 / 43
serious
Total, serious adverse events
0 / 440 / 430 / 43

Outcome results

Primary

Maximal Platelet Aggregation

The primary end point of our study is the comparison of maximal platelet aggregation measured by light transmittance aggregometry using CAT (collagen-ADP-TRAP) between DAPT and DAPT plus vorapaxar after 30 days of treatment.

Time frame: 30 days

Population: 130 patients were randomized and exposed to at least one dose of study medication (triple therapy, n=44; dual therapy, n= 43; DAPT, n=43). Of these, 115 patients (triple therapy, n=37; dual therapy, n= 39; DAPT, n=39) had valid primary endpoint data

ArmMeasureValue (MEAN)Dispersion
DAPT Plus VorapaxarMaximal Platelet Aggregation52 percent aggregationStandard Deviation 21
Prasugrel/Ticagrelor Plus VorapaxarMaximal Platelet Aggregation64 percent aggregationStandard Deviation 20
DAPTMaximal Platelet Aggregation74 percent aggregationStandard Deviation 10
Comparison: We hypothesized that adjunctive vorapaxar would result in a significant reduction of CAT-induced platelet aggregation. Assuming a 10% absolute reduction in CAT-induced maximal platelet aggregation with a common standard deviation of 13%, 37 patients per group with valid primary endpoint data were required to detect a significant difference with a 90% power and 2-sided alpha=0.05.p-value: 0.01195% CI: [19, 34]ANOVA

Source: ClinicalTrials.gov · Data processed: Mar 2, 2026