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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
INTEnsive blood pressure Reduction in Acute Cerebral haemorrhage Trial
Scientific title
A randomised trial to establish the effects of early intensive blood pressure lowering on death and disability in patients with stroke due to acute intracerebral haemorrhage
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Intracerebral haemorrhage 495 0
Condition category
Condition code
Stroke 575 575 0 0

Study type
Description of intervention(s) / exposure
The trial has 2 phases a) Vanguard phase to establish the safety, potential efficiency and feasibility of conducting a large scale study; and b) Main phase to establish the effects of a management policy of early intensive blood pressure lowering on death & disability in patients with primary intracerebral haemorrhage compared to current guideline based management of high blood pressure in this setting.

Patients will be randomised to either intensive blood pressure lowering or current guideline based management.

The drugs used are all licensed for this indication and are labetolol hydrochloride, metoprolol tartrate, hydralazine hydrochloride, glyceral trinitrate and phentoloamine.

Intensive therapy is given via an intravenous drip for 24 hours. The target is to reach a systolic BP <140mmHg within 1 hour and to maintain this pressure during hospitalisation and for 3 months post hospitalisation. Oral or nasogastric treatment should be commenced within 24 hours. Control group therapy is given using oral or nasogastric tube and intravenous medication is only used if systolic blood pressure rises above 180mmHg. The target of control therapy is to manage blood pressure according to guidelines, which state blood pressure should be <180mmHg.
The duration of intervention is 3 months for both groups.
Intervention code [1] 353 0
Treatment: Drugs
Comparator / control treatment
Usual care - standard Blood Pressure lowerng based on the American Heart Association (AHA)
Control group

Primary outcome [1] 660 0
Timepoint [1] 660 0
At 3 months
Primary outcome [2] 661 0
Timepoint [2] 661 0
At 3 months
Secondary outcome [1] 1368 0
All cause and cause specific early neurological deterioration
Timepoint [1] 1368 0
During the first 72 hours measured by reduction by 2 points in GCS or increase by 2 points in NIHSS from baseline.
Secondary outcome [2] 1369 0
Haematoma expansion during the first 72 hours
Timepoint [2] 1369 0
Measured by CT scans at 24 and 72 hours.
Secondary outcome [3] 1370 0
Cerebral oedema during the first 72 hours
Timepoint [3] 1370 0
Measured by CT scans at 24 and 72 hours.
Secondary outcome [4] 1371 0
Functional disability
Timepoint [4] 1371 0
At Day 7, Day 28 and Day 90 using mRS and Barthel Index.
Secondary outcome [5] 1372 0
Cognitive function
Timepoint [5] 1372 0
At Day 28 and Day 90 using MMSE
Secondary outcome [6] 1373 0
Health Related Quality of Life
Timepoint [6] 1373 0
At Day 28 and Day 90 using EuroQuol5D
Secondary outcome [7] 1374 0
Recurrent stroke
Timepoint [7] 1374 0
At Day 28 and Day 90
Secondary outcome [8] 1375 0
Acute myocardial infarction or sudden death from a cardiovascular cause.
Timepoint [8] 1375 0
At Day 28 and Day 90

Key inclusion criteria
Patients with CT-confirmed spontaneous Intracerebral Haemorrhage (ICH) and elevated systolic BP (>150mmHg and <220mmHg), capacity to commence randomly assigned treatment with 6 hours of onset of ICH.
Minimum age
18 Years
Maximum age
Not stated
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Clear indication for or contraindication for intensive BP lowering. Evidence ICH secondary to a structural abnormality, or use of thrombolytic agent, an ischemic stroke within 30 days, a score of 3-5 on the Galsgow Coma Scale (indicating a deep coma), significant pre-stroke disability or medical illness and planned early neurosurgical intervention.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Randomisation is performed through the centralised web-based interface and the treatment group is concealed until assigned.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Assignment to a treatment group is determined by a computerised algorithm which runs on the central database and uses the minimisation method. The stratification factors are country and time since onset.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 164 0
State/province [1] 164 0
Country [2] 165 0
Korea, Republic Of
State/province [2] 165 0

Funding & Sponsors
Funding source category [1] 625 0
Government body
Name [1] 625 0
National Health & Medical Research Council
Address [1] 625 0
GPO Box 1421
Canberra ACT 2601
Country [1] 625 0
Primary sponsor type
The George Institute for International Health
PO Box M201
Missenden Road
Camperdown NSW 2050
Secondary sponsor category [1] 510 0
Name [1] 510 0
Address [1] 510 0
Country [1] 510 0

Ethics approval
Ethics application status
Ethics committee name [1] 1760 0
Box Hill Hospital
Ethics committee address [1] 1760 0
Ethics committee country [1] 1760 0
Date submitted for ethics approval [1] 1760 0
Approval date [1] 1760 0
Ethics approval number [1] 1760 0

Brief summary
INTERACT is an academic, international clinical trial to establish the possibility of undertaking a large scale study in 6,000 patients with acute intracerebral haemorrhage (bleeding into the brain) within 6 hours of onset and who also have associated high blood pressure.
400 patients will be recruited from Australia, New Zealand, China, Singapore and the United States of America. Patients will be assigned to either intensive blood pressure lowering treatment or current guideline based management of blood pressure alongside routine stroke management. Participants will be visited for 7 days during their hospital stay and then followed up at 1 month and 3 months intervals.
The majority of information will be collected using standardised questionnaires and stroke scales. The study is a trial of blood pressure lowering policy using approved drugs within their labelling restrictions.
The main purpose of the studyis to review the numbers of deaths and number of patients permanenetly disabled at 3 months.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 35928 0
Address 35928 0
Country 35928 0
Phone 35928 0
Fax 35928 0
Email 35928 0
Contact person for public queries
Name 9542 0
Emma Heeley
Address 9542 0
The George Institute
Royal Prince ALfred Hospital
Level 10
King George V Building
Missenden Road
Camperdown NSW 2050
Country 9542 0
Phone 9542 0
+61 299934561
Fax 9542 0
+61 2 99934502
Email 9542 0
Contact person for scientific queries
Name 470 0
Craig Anderson
Address 470 0
The George Institute
Royal Prince ALfred Hospital
Level 10
King George V Building
Missenden Road
Camperdown NSW 2050
Country 470 0
Phone 470 0
+61 2 99934590
Fax 470 0
+61 2 99934502
Email 470 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary