StrokeCOOLHEAD-2BNCT07526649
Head Cooling in Ischaemic Stroke Patients Undergoing Endovascular Thrombectomy (COOLHEAD-2b)
A study testing Non-invasive convective head cooling in people with Stroke and Acute Ischemic Stroke, run by Auckland City Hospital at 1 site in New Zealand.
Trial summary
COOLHEAD-2b is a multicentre, phase 2, prospective, randomised, controlled, open-label, blinded-endpoint trial evaluating the safety and efficacy of non-invasive convective head cooling as an adjunct to endovascular thrombectomy (EVT) in patients with acute anterior circulation ischaemic stroke. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Stroke, Acute Ischemic Stroke, Brain Ischemia
- What is being tested?
- Non-invasive convective head cooling
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 182 participants
- Where
- 1 siteNew Zealand
- Study dates
- 10 Apr 2026to 30 Jun 2029
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Acute anterior circulation ischaemic stroke planned for endovascular thrombectomy
- Age ≥18 years
Who cannot join
- Pre-stroke modified Rankin Scale score >2
- Core body temperature <35°C at admission
- Uncontrolled hypertension (≥185/110 mmHg despite treatment in IVT-eligible patients)
- Known contraindications to hypothermia (e.g., haemodynamic instability, symptomatic bradyarrhythmia, cryoglobulinaemia, sickle cell disease, cold agglutinins)
- Vasospastic disorders (e.g., Raynaud's phenomenon)
- Skin lesions preventing secure application of the cooling cap
- Inability to participate in 90-day follow-up
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
New Zealand1 site
Health New Zealand - Auckland
Grafton, Auckland, 1023
Davina J McAllister, DipNursing, 0274891940, davina.mcallister@tewhatuora.govt.nz
Jessica Wiles, BHSc - Nursing, jessica.wiles@TeWhatuOra.govt.nz
About this study
Official title: Head Cooling in Ischaemic Stroke Patients Undergoing Endovascular Thrombectomy: A Phase 2 Randomised Controlled Trial (COOLHEAD-2b)
COOLHEAD-2b is a multicentre, phase 2, prospective, randomised, controlled, open-label, blinded-endpoint trial evaluating the safety and efficacy of non-invasive convective head cooling as an adjunct to endovascular thrombectomy (EVT) in patients with acute anterior circulation ischaemic stroke. Head cooling is initiated as early as possible, including during inter-hospital transfer, and continued until one hour after reperfusion. The primary efficacy endpoint is final infarct volume at 24 hours.
Read the detailed description
Despite advances in reperfusion therapy, a substantial proportion of patients undergoing EVT for acute ischaemic stroke experience poor functional outcomes, particularly those with delayed reperfusion due to interhospital transfer. Therapeutic hypothermia is a potent neuroprotective intervention in preclinical stroke models but has not been successfully translated into clinical practice due to delayed initiation and systemic complications.
Convective head cooling is a non-invasive, portable method capable of selectively reducing brain temperature while minimizing systemic hypothermia. Phase 1 and feasibility studies (COOLHEAD-1 and COOLHEAD-2a) demonstrated that this approach is safe, well-tolerated, and feasible in patients undergoing EVT.
COOLHEAD-2b will test whether convective head cooling reduces infarct volume and improves clinical outcomes when applied early and continued throughout the EVT workflow, including interhospital transfer. Participants will be randomised 1:1 to head cooling plus standard care or standard care alone. Outcome assessors and imaging core laboratory staff will be blinded to treatment allocation.
All outcome measures are derived from prospectively collected clinical, imaging, and procedural data. Imaging outcomes are assessed by a blinded core laboratory using standardized methods. Functional outcome assessments are performed by trained assessors blinded to treatment allocation. Safety outcomes are actively monitored throughout the peri-procedural and post-procedural periods.
- Conditions
- Stroke, Acute Ischemic Stroke, Brain Ischemia, Ischaemic Stroke, Thrombectomy, Endovascular Procedures
- Being tested
- Non-invasive convective head cooling, Standard of Care (SOC)
- Keywords
- Head cooling, Selective brain cooling, Endovascular thrombectomy, Therapeutic hypothermia, Penumbra, Neuroprotection
- Medical subject headings
- Stroke, Ischemic Stroke, Brain Ischemia, Reperfusion Injury
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Non-invasive convective head coolingDevice
Non-invasive convective head cooling delivered using a cooling cap system that circulates chilled fluid around the scalp and neck. Cooling is commenced in the emergency department following randomisation, with a target coolant temperature of -5 °C (adjustable for comfort). Cooling is continued during interhospital transfer (if applicable), during the endovascular thrombectomy procedure, and for one hour following reperfusion. Systemic rewarming measures may be used to maintain core body temperature above 35 °C if required.
Standard of Care (SOC)Other
Guideline-based management of acute ischaemic stroke, including endovascular thrombectomy, with supportive medical care as determined by the treating clinical team. No head cooling device is applied.
| Study group | Role | What they receive |
|---|---|---|
| Non-invasive Convective Head Cooling + Standard of Care | Experimental | Participants receive non-invasive convective head cooling in addition to standard clinical care for acute anterior circulation ischaemic stroke undergoing endovascular thrombectomy. Head cooling is initiated as early as possible following randomisation and continued throughout interhospital transfer (if applicable), endovascular thrombectomy, and for one hour after reperfusion. Receives: Device: Non-invasive convective head cooling |
| Standard of Care (SOC) Alone | Active comparator | Participants receive standard clinical care for acute anterior circulation ischaemic stroke undergoing endovascular thrombectomy, without head cooling. Receives: Other: Standard of Care (SOC) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Final Infarct Volume
Final infarct volume (mL), defined as the manually segmented volume of infarcted brain tissue on 24-hour follow-up CT or MRI brain imaging. Segmentation will be performed by a blinded imaging core laboratory using de-identified imaging files.
Measured: 24 hours after endovascular thrombectomy
Secondary outcomes (7)
Infarct growth
Infarct growth, defined as the difference between the final infarct volume on 24-hour follow-up imaging and the baseline infarct core volume estimated using automated CT perfusion software (relative cerebral blood flow <30%).
Measured: Baseline imaging to 24 hours after endovascular thrombectomy
Penumbral salvage index
Penumbral salvage index, defined as the proportion of baseline hypoperfused or penumbral brain tissue not progressing to infarction, calculated using baseline CT perfusion imaging and final infarct volume on 24-hour follow-up imaging.
Measured: Baseline imaging to 24 hours after endovascular thrombectomy
Early neurological improvement
Early neurological improvement, defined as the percentage change in the National Institutes of Health Stroke Scale (NIHSS), a neurological deficit scale ranging from 0 to 42 where higher scores indicate worse neurological impairment, from baseline to 24 hours
Measured: Baseline to 24 hours after endovascular thrombectomy
Modified Rankin Scale (mRS) score
Degree of disability or dependence in daily activities measured using the modified Rankin Scale (mRS), an ordinal scale ranging from 0 (no symptoms) to 6 (death), where higher scores indicate greater disability. Assessment is performed by a trained, blinded study team member using the Rankin Focused Assessment.
Measured: 90 days after endovascular thrombectomy
Proportion of Participants with Functional Independence
Proportion of participants achieving functional independence, defined as a modified Rankin Scale (mRS) score of 0 to 2, where lower scores indicate less disability.
Measured: 90 days after endovascular thrombectomy
Proportion of Participants with Excellent Functional Outcome
Proportion of participants achieving an excellent functional outcome defined as a modified Rankin Scale (mRS) score of 0 to 1, where lower scores indicate minimal or no disability.
Measured: 90 Days post endovascular thrombectomy
Days Alive and Out of Hospital (DAOH-90)
Number of days participants are alive and not admitted to hospital during the first 90 days after endovascular thrombectomy.
Measured: First 90 days after endovascular thrombectomy
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Apr 2026
- Study start10 Apr 2026 (estimated)
- Primary completion31 Dec 2028 (estimated)
- Study completion30 Jun 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for StrokeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This is a randomized, controlled trial evaluating a non-pharmacological device intervention (non-invasive convective head cooling) as an adjunct to standard endovascular thrombectomy care."
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 182 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Auckland City Hospital
- Sponsor type
- Other government
- Collaborators
- Neurological Foundation of New Zealand, Health New Zealand
- Responsible party
- Sponsor
- Investigators
- William Diprose, MBChB, Principal investigator, University of Auckland, New ZealandAlan Barber, PhD, Principal investigator, University of Auckland, New ZealandDoug Campbell, MBChB, Principal investigator, Auckland City Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07526649
- Sponsor's protocol ID
- COOLHEAD-2B
- Other IDs
- A+10418
- Acronym
- COOLHEAD-2B
- Status last verified
- Apr 2026
- First submitted
- 29 Mar 2026
- Last updated
- 13 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data (IPD) will not be shared outside the study team. This trial involves detailed clinical, imaging, and procedural data collected within a relatively small and geographically defined population, which increases the risk of participant re-identification despite de-identification. In addition, no consent for broader data sharing beyond the study investigators was obtained from participants or their representatives. Access to the final dataset will therefore be restricted to the study investigators for the purposes of scientific analysis and publication.
Publications
Rinkel LA, Ospel JM, Brown SB, Campbell BCV, Dippel DWJ, Demchuk AM, Majoie CBLM, Mitchell PJ, Bracard S, Guillemin F, Jovin TG, Muir KW, White P, Saver JL, Hill MD, Goyal M; HERMES Collaborators. What Is a Meaningful Difference When Using Infarct Volume as the Primary Outcome?: Results From the HERMES Database. Stroke. 2024 Apr;55(4):866-873. doi: 10.1161/STROKEAHA.123.044353. Epub 2024 Mar 5.
PubMed 38440891Jabonero V, Martinez R, Marin Giron F, Jabonero RM. [Studies on synapses of the peripheral vegetative nervous system. V. Additional observations on the ending systems of postganglionic nerve fibers]. Z Mikrosk Anat Forsch. 1965;73(1):96-116. No abstract available. German.
PubMed 4161451Wang H, Olivero W, Lanzino G, Elkins W, Rose J, Honings D, Rodde M, Burnham J, Wang D. Rapid and selective cerebral hypothermia achieved using a cooling helmet. J Neurosurg. 2004 Feb;100(2):272-7. doi: 10.3171/jns.2004.100.2.0272.
PubMed 15086235Diprose WK, Wang MTM, Campbell D, Sutcliffe JA, McFetridge A, Chiou D, Lai J, Barber PA. Intravenous Propofol Versus Volatile Anesthetics For Stroke Endovascular Thrombectomy. J Neurosurg Anesthesiol. 2021 Jan;33(1):39-43. doi: 10.1097/ANA.0000000000000639.
PubMed 31453877Svensson B. [The prevalence of rheumatoid arthritis is lower than previously known]. Lakartidningen. 1989 Jan 4;86(1-2):45-6. No abstract available. Swedish.
PubMed 2783474van der Worp HB, Sena ES, Donnan GA, Howells DW, Macleod MR. Hypothermia in animal models of acute ischaemic stroke: a systematic review and meta-analysis. Brain. 2007 Dec;130(Pt 12):3063-74. doi: 10.1093/brain/awm083. Epub 2007 May 3.
PubMed 17478443Goyal M, Menon BK, van Zwam WH, Dippel DW, Mitchell PJ, Demchuk AM, Davalos A, Majoie CB, van der Lugt A, de Miquel MA, Donnan GA, Roos YB, Bonafe A, Jahan R, Diener HC, van den Berg LA, Levy EI, Berkhemer OA, Pereira VM, Rempel J, Millan M, Davis SM, Roy D, Thornton J, Roman LS, Ribo M, Beumer D, Stouch B, Brown S, Campbell BC, van Oostenbrugge RJ, Saver JL, Hill MD, Jovin TG; HERMES collaborators. Endovascular thrombectomy after large-vessel ischaemic stroke: a meta-analysis of individual patient data from five randomised trials. Lancet. 2016 Apr 23;387(10029):1723-31. doi: 10.1016/S0140-6736(16)00163-X. Epub 2016 Feb 18.
PubMed 26898852