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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Ticagrelor and platelet reactivity in acute coronary syndromes
Scientific title
Acute Coronary Syndrome patients and the effects of ticagrelor loading dose on level of platelet inhibition
Secondary ID [1] 283504 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Acute Coronary Syndrome 290422 0
Condition category
Condition code
Cardiovascular 290814 290814 0 0
Coronary heart disease

Study type
Description of intervention(s) / exposure
Randomised, double-blind clinical trial comparing the effects of a single 180mg Ticagrelor loading dose given orally (control) with a single 360mg Ticagrelor loading dose given orally (intervention) on platelet inhibition in patients with acute coronary syndromes. This is the initial treatment, following which patients will undergo angiography. Depending on the findings at angiography patients may be prescribed dual anti platelet therapy (ticagrelor and aspirin) daily for up to 1 year, but this is beyond the scope of this study, which is only investigating the effects of the initial loading dose.
Intervention code [1] 288210 0
Treatment: Drugs
Comparator / control treatment
180mg Ticagrelor compared to 360mg Ticagrelor loading dose.
Control group

Primary outcome [1] 290808 0
Level of platelet inhibition measured using platelet impedance aggregometry at 2 hours (using Multiplate system).
Timepoint [1] 290808 0
2 hours after loading dose
Secondary outcome [1] 305340 0
Level of platelet inhibition measured using platelet impedance aggregometry at 1, 4 and 8 hours (using Multiplate system).
Timepoint [1] 305340 0
at 1 hour, 4 hours and 8 hours after loading dose

Key inclusion criteria
Acute coronary syndrome
Minimum age
30 Years
Maximum age
90 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Known platelet function disorder
Platelet count less than 100
Prior administration of a P2Y12 receptor antagonist within 2 weeks

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Patients with acute coronary syndrome requiring dual antiplatelet therapy will be enrolled in the study.

Random numbers contained in sealed envelopes will be used for study enrolment and treatment allocation
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random number allocation using custom written computer software
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Phase 4
Type of endpoint(s)
Statistical methods / analysis
Comparison of level of platelet inhibition at 2 hours using non-parametric statistic (Mann Whitney U test). Based upon the RAPID study ( J Am Coll Cardiol. 2013 Apr 16;61(15):1601–6) data and the assumption that a difference of more than 20% would be required to be statistically significant, a sample size of 25 per group is required to give 80% probability of detecting this difference at p=0.05.

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 5552 0
New Zealand
State/province [1] 5552 0

Funding & Sponsors
Funding source category [1] 288204 0
Self funded/Unfunded
Name [1] 288204 0
Address [1] 288204 0
Country [1] 288204 0
Primary sponsor type
Peter Larsen
University of Otago, Wellington
PO Box 7343
New Zealand
Secondary sponsor category [1] 286930 0
Name [1] 286930 0
Address [1] 286930 0
Country [1] 286930 0
Other collaborator category [1] 277681 0
Name [1] 277681 0
Cardiology Department
Wellington Hospital
Address [1] 277681 0
Wellington Hospital
Riddiford St
Wellington 6021
Country [1] 277681 0
New Zealand

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 290116 0
Heath and Disability Ethics Committee
Ethics committee address [1] 290116 0
Ministry of Health
No 1 The Terrace
PO Box 5013
Wellington 6001
Ethics committee country [1] 290116 0
New Zealand
Date submitted for ethics approval [1] 290116 0
Approval date [1] 290116 0
Ethics approval number [1] 290116 0

Brief summary
Following a heart attack we give all patients drugs that act on platelets that circulate in the blood. These drugs, aspirin and ticagrelor, act on the platelets to limit the amount of blood clotting that occurs following the heart attack. The standard amount of ticagrelor we give people initially is 180mg. A study has shown that with this amount of the drug it can take 8 to 12 hours until the full effect of the drug is observed. We want to know if by doubling the initial dose to 360mg we can reduce the time it takes to see the full effects.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 44050 0
A/Prof Peter Larsen
Address 44050 0
University of Otago, Wellington
PO Box 7343
Wellington 6242
Country 44050 0
New Zealand
Phone 44050 0
Fax 44050 0
Email 44050 0
Contact person for public queries
Name 44051 0
A/Prof Peter Larsen
Address 44051 0
University of Otago, Wellington
PO Box 7343
Wellington 6242
Country 44051 0
New Zealand
Phone 44051 0
Fax 44051 0
Email 44051 0
Contact person for scientific queries
Name 44052 0
A/Prof Peter Larsen
Address 44052 0
University of Otago, Wellington
PO Box 7343
Wellington 6242
Country 44052 0
New Zealand
Phone 44052 0
Fax 44052 0
Email 44052 0

No information has been provided regarding IPD availability
Summary results
No Results