Condition category
Circulatory System
Date applied
10/07/2008
Date assigned
18/07/2008
Last edited
12/04/2016
Prospective/Retrospective
Prospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
An intracerebral haemorrhage (ICH) occurs when a blood vessel in the brain bursts and bleeds into the brain. ICH is one of the most serious types of stroke, affecting over a million people worldwide each year. About one third of people with ICH die soon after and most survivors are left with major long-term disability. Despite the size of the disease burden and the cost on healthcare resources, there remains uncertainty about the role of surgery and medical treatments for ICH. There is evidence that lowering blood pressure (BP) reduces stroke risk. Although BP levels are commonly high early after the onset of stroke, particularly in ICH, the effects of BP lowering treatment in the acute phase of stroke remain unknown. As a consequence, there are wide ranging guideline recommendations for managing high BP. The aim of this study is to assess the effects of early intensive BP lowering on patients with ICH and high BP, compared with more conservative BP management.

Who can participate?
Patients with acute ICH (within 6 hours of onset) and high BP (between 150 and 220 mmHg).

What does the study involve?
Patients are randomly allocated to either intensive or conservative management of BP. Treatment starts as soon as possible after allocation (e.g., in the emergency department) and is continued in a monitored facility (i.e., intensive care unit, high dependency unit or stroke unit). For patients allocated to the intensive BP lowering group the treatment goal is to achieve BP of less than 140 mmHg within one hour of starting treatment. The second goal is to maintain the BP at 140 mmHg or less or at least 7 days in hospital, and subsequently on discharge and for 90 days. Patients allocated to the conservative BP lowering group receive BP management that is based on American Heart Association (AHA) guidelines. In this group, treatment is started if BP is over 180 mmHg. For both groups, patients must be on an oral blood pressure lowering drug by day 7 or at discharge from hospital, with a long-term target BP of 140 mmHg, as per the guidelines. Information is collected at the time of allocation and follow-up data is collected on four occasions: after 24 hours and 7 days (or at the time of death or hospital discharge, if this should occur before day 7), and after 28 days and 90 days, with the last two assessments carried out either in-person or over the telephone.

What are the possible benefits and risks of participating?
Not provided at time of registration

Where is the study run from?
The George Institute Royal Prince Alfred Hospital (Australia)

When is the study starting and how long is it expected to run for?
September 2008 to December 2012

Who is funding the study?
National Health and Medical Research Council (NHMRC) (Australia)

Who is the main contact?
Prof Craig Anderson

Trial website

http://www.interact2.org/

Contact information

Type

Scientific

Primary contact

Prof Craig Anderson

ORCID ID

Contact details

The George Institute Royal Prince Alfred Hospital
Level 10 King George V Building
Missenden Road
Camperdown
Sydney
2050
Australia

Additional identifiers

EudraCT number

ClinicalTrials.gov number

NCT00716079

Protocol/serial number

NHMRC-571281, ACTRN12608000362392

Study information

Scientific title

An international randomised controlled trial to establish the effects of early intensive blood pressure lowering in patients with intracerebral haemorrhage

Acronym

INTERACT2

Study hypothesis

The purpose of this academic lead study is to determine if a treatment strategy of early intensive blood pressure (BP) lowering compared to conservative BP lowering policy in patients with elevated blood pressure within 6 hours of acute intracerebral haemorrhage (ICH) improves the outcome of death and disability at 3 months after onset.

Ethics approval

SSWAHS Ethics Review Committee (RPAH Zone), 26/06/2008, ref: 08/RPAH/273

Study design

Multicentre treatment parallel-assignment two-armed open-label randomised active-controlled safety/efficacy study

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Not available in web format, please contact cdelcourt@george.org.au or canderson@george.org.au to request a patient information sheet

Condition

Intracerebral haemorrhage

Intervention

Intensive arm:
Intensive blood pressure (BP) lowering therapy is given via an intravenous drip for 24 hours. The target is to reach a systolic BP less than 140 mmHg within 1 hour.

Conservative arm:
Patients will receive management of BP that is based on a standard guideline, as published by the American Heart Association (AHA). The attending clinician may consider commencing BP treatment if the systolic level is greater than 180 mmHg, however and the first line treatment will be oral (including nasogastric if required) and/or transdermal routes. Should control of systolic BP not be achieved via these routes, intravenous treatment may be started until the target systolic BP of 180 mmHg is achieved.

Intervention:
Blood pressure management policies:
The trial is an assessment of BP lowering management strategies, using routinely available drugs. There is some flexibility in the use of particular BP lowering agents to achieve BP targets.

Intervention type

Drug

Phase

Not Applicable

Drug names

Labetalol hydrochloride, metoprolol tartrate, hydralazine hydrochloride, glycerol trinitrate, phentolamine mesylate, nicardipine, urapidil, esmolol, clonidine, enalaprilat, nitroprusside

Primary outcome measures

A composite of death or dependency, with dependency being defined by a score of 3 to 5 on the Modified Rankin Scale (mRS). Timeframe: 90 days.

Secondary outcome measures

1. Death and dependency in patients treated less than 4 hours
2. Death
3. Dependency
4. Health Related Quality of Life (HRQoL)
5. Physical function
6. Recurrent vascular events
7. Days of hospitalisation
8. Permanent residential care

Timeframe: 90 days

Overall trial start date

01/09/2008

Overall trial end date

31/12/2012

Reason abandoned

Eligibility

Participant inclusion criteria

1. Patients with computed tomography (CT)-confirmed spontaneous intracerebral haemorrhage (ICH)
2. Elevated systolic blood pressure (greater than 150 mmHg and less than 220 mmHg)
3. Capacity to commence randomly assigned treatment within 6 hours of onset of ICH
4. Able to be 'actively' treated and admitted to a monitored facility
5. Male and female, aged older than 18 years old

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

2839

Participant exclusion criteria

1. Clear indication or contraindication to intensive BP lowering
2. Evidence ICH secondary to a structural abnormality
3. Use of thrombolytic agent
4. Previous ischaemic stroke within 30 days
5. A very high likelihood that the patient will die within the next 24 hours on the basis of clinical and/or radiological criteria
6. Score of 3 - 5 on the Glasgow Coma Scale (indicating deep coma)
7. Significant pre-stroke disability or advanced dementia
8. Planned early neurological intervention
9. Participation in another clinical trial
10. A high likelihood that the patient will not adhere to the study treatment and follow-up regimen

Recruitment start date

01/09/2008

Recruitment end date

31/12/2012

Locations

Countries of recruitment

Argentina, Australia, Austria, Belgium, Brazil, Chile, China, Finland, France, Germany, Hong Kong, India, Italy, Netherlands, Norway, Pakistan, Portugal, Spain, Switzerland, United Kingdom, United States of America

Trial participating centre

The George Institute Royal Prince Alfred Hospital
Sydney
2050
Australia

Sponsor information

Organisation

National Health and Medical Research Council (NHMRC) (Australia)

Sponsor details

GPO Box 1421
ACT 2601
Canberra
2601
Australia
+61 (0)1800 500 983
grantnet.help@nhmrc.gov.au

Sponsor type

Research council

Website

http://www.nhmrc.gov.au/

Funders

Funder type

Research council

Funder name

National Health and Medical Research Council (NHMRC) (Australia)

Alternative name(s)

NHMRC

Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government

Location

Australia

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

See https://clinicaltrials.gov/ct2/show/results/NCT00716079

Publication summary

1. 2008 pilot study results in http://www.ncbi.nlm.nih.gov/pubmed/18396107
2. 2010 protocol in http://www.ncbi.nlm.nih.gov/pubmed/20446945
3. 2012 results in http://www.ncbi.nlm.nih.gov/pubmed/22129475
4. 2013 results in http://www.ncbi.nlm.nih.gov/pubmed/23713578
5. 2014 results in: http://www.ncbi.nlm.nih.gov/pubmed/24530176

Publication citations

  1. Pilot study results

    Anderson CS, Huang Y, Wang JG, Arima H, Neal B, Peng B, Heeley E, Skulina C, Parsons MW, Kim JS, Tao QL, Li YC, Jiang JD, Tai LW, Zhang JL, Xu E, Cheng Y, Heritier S, Morgenstern LB, Chalmers J, , Intensive blood pressure reduction in acute cerebral haemorrhage trial (INTERACT): a randomised pilot trial., Lancet Neurol, 2008, 7, 5, 391-399, doi: 10.1016/S1474-4422(08)70069-3.

  2. Protocol

    Delcourt C, Huang Y, Wang J, Heeley E, Lindley R, Stapf C, Tzourio C, Arima H, Parsons M, Sun J, Neal B, Chalmers J, Anderson C, , The second (main) phase of an open, randomised, multicentre study to investigate the effectiveness of an intensive blood pressure reduction in acute cerebral haemorrhage trial (INTERACT2)., Int J Stroke, 2010, 5, 2, 110-116, doi: 10.1111/j.1747-4949.2010.00415.x.

  3. Results

    Delcourt C, Stapf C, Tzourio C, Héritier S, Anderson C, [The second (main) phase of an open, randomised, multicentre study to investigate the effectiveness of an INTEnsive blood pressure Reduction in Acute Cerebral hemorrhage Trial (INTERACT2): protocol and baseline characteristics of patients included in France]., Rev. Neurol. (Paris), 2012, 168, 4, 321-327, doi: 10.1016/j.neurol.2011.08.010.

  4. Results

    Anderson CS, Heeley E, Huang Y, Wang J, Stapf C, Delcourt C, Lindley R, Robinson T, Lavados P, Neal B, Hata J, Arima H, Parsons M, Li Y, Wang J, Heritier S, Li Q, Woodward M, Simes RJ, Davis SM, Chalmers J, , Rapid blood-pressure lowering in patients with acute intracerebral hemorrhage., N. Engl. J. Med., 2013, 368, 25, 2355-2365, doi: 10.1056/NEJMoa1214609.

  5. Results

    Manning L, Hirakawa Y, Arima H, Wang X, Chalmers J, Wang J, Lindley R, Heeley E, Delcourt C, Neal B, Lavados P, Davis SM, Tzourio C, Huang Y, Stapf C, Woodward M, Rothwell PM, Robinson TG, Anderson CS, , Blood pressure variability and outcome after acute intracerebral haemorrhage: a post-hoc analysis of INTERACT2, a randomised controlled trial., Lancet Neurol, 2014, 13, 4, 364-373, doi: 10.1016/S1474-4422(14)70018-3.

Additional files

Editorial Notes

12/04/2016: Plain English summary added. 24/03/2016: added link to results - basic reporting. On 24/07/2013 Argentina, Brazil, Chile, Finland, Hong Kong, India, Italy, Norway, Pakistan, Portugal and the USA were added to the countries of recruitment, and New Zealand was removed. The target number of participants was also changed from 2800 to 2839. On 19/09/2012 the overall trial end date was changed from 30/06/2012 to 31/12/2012. On 06/09/2011 the overall trial end date was changed from 01/09/2011 to 30/06/2012.