Giant Cell ArteritisATOM-GCANCT05703763
The Applanation Tonometry in GCA Pilot
An observational study of Giant Cell Arteritis, run by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal at 1 site in Canada.
Trial summary
The Applanation Tonometry in Giant Cell Arteritis (ATOM-GCA) study will answer the following questions: 1. How does PWV, measured by applanation tonometry of temporal arteries, differ between patients with and without a final diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)? 2. Read more about this study
- Who is it for?
- Ages 50 to 99 years
- Conditions the study is for
- Giant Cell Arteritis
- What is being tested?
- Applanation tonometry, Standardized GCA assessment and Repeat applanation tonometry (optional)
- How many people
- 146 participants
- Where
- 1 siteCanada
- Study dates
- 30 Jul 2025to Jul 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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 50 to 99 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Consecutive patients referred for suspected new-onset GCA
Who may be able to join
- To be included in ATOM-GCA, participants must meet all the following criteria:
- Age > 50 years.
- Referral for suspected, new-onset GCA.
- Ability to understand and willingness to sign an informed consent form.
- Willingness to comply with study visits and procedures.
Who cannot join
- An individual who meets any of these criteria will be excluded from ATOM-GCA:
- Referral for a suspected GCA relapse.
- Current use of systemic glucocorticoids, with the following duration at the baseline visit:
- ≥ 14 consecutive days of oral glucocorticoids in the previous 30 days, or
- ≥ 7 consecutive days of oral glucocorticoids if intravenous glucocorticoids were administered in the previous 30 days.
- Current use of any conventional or biologic immunosuppressive therapy.
- Temporal artery biopsy prior to the study visit.
Trial locations and contacts
1 site in 1 country.
Canada1 site
Vasculitis Clinic, Hopital du Sacre-Coeur de Montreal
Montreal, Quebec, H4J1C5
About this study
Official title: The Applanation Tonometry in Giant Cell Arteritis Pilot
The Applanation Tonometry in Giant Cell Arteritis (ATOM-GCA) study will answer the following questions:
- How does PWV, measured by applanation tonometry of temporal arteries, differ between patients with and without a final diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?
- What is the diagnostic accuracy and positivity cutoff of the PWV, measured by applanation tonometry, in detecting:
- A clinical diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?
- Inflammation of temporal arteries on high-resolution ultrasound?
- What is the acceptability and adherence of repeat applanation tonometry during the follow-up period in patients with GCA?
Read the detailed description
ATOM-GCA is a single-center, cross-sectional vanguard study.
- Conditions
- Giant Cell Arteritis
- Being tested
- Applanation tonometry, Standardized GCA assessment, Repeat applanation tonometry (optional)
- Keywords
- diagnosis
- Medical subject headings
- Giant Cell Arteritis, Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Applanation tonometryDiagnostic test
Applanation tonometry will be used to measure arterial stiffness in these segments, bilaterally:
- Superficial temporal artery to frontal temporal artery
- Common carotid artery to superficial temporal artery
Standardized GCA assessmentDiagnostic test
Clinical assessment, blood test review, high-resolution temporal artery ultrasound using a 24mHz probe.
Repeat applanation tonometry (optional)Diagnostic test
Repeat index test at month 6 and at disease relapse.
| Study group | Role | What they receive |
|---|---|---|
| GCA group | Definite confirmation of GCA will occur 6 months after study inclusion, following the phone follow-up, and will require all the following features: 1) initial symptoms and clinical evolution consistent with GCA; 2) at least one positive test for cranial GCA (ultrasound of temporal arteries, temporal artery biopsy, cranial MRI, cranial PET); and 3) satisfies the 2022 ACR-EULAR classification criteria for GCA. Receives: Diagnostic Test: Applanation tonometry; Diagnostic Test: Standardized GCA assessment; Diagnostic Test: Repeat applanation tonometry (optional) | |
| Non-GCA group | Participants who do not meet the criteria (above) for GCA at month 6. Receives: Diagnostic Test: Applanation tonometry; Diagnostic Test: Standardized GCA assessment |
What is being measured
The primary outcome is the main question the study is designed to answer.
PWV in patients with and without GCA
The primary outcome of ATOM-GCA is to compare the mean PWV in patients with GCA to the mean PWV in individuals without GCA. Final confirmation of GCA will be determined 6 months after study inclusion. This analysis will establish whether the PWV differs in GCA. Additionally, we will explore the optimal PWV cutoff and evaluate its diagnostic performance to confirm a final diagnosis of GCA at 6 months.
Measured: Baseline
Secondary outcomes (1)
Diagnostic performance of the PWV
The secondary outcome is to assess the diagnostic performance of the PWV to predict the presence of GCA-induced inflammation on high-resolution ultrasound. This analysis will identify the optimal PWV cutoff to potentially replace temporal artery ultrasound in GCA diagnosis.
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jan 2023
- Study start30 Jul 2025
- Primary completionMar 2027 (estimated)
- Study completionJul 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Giant Cell ArteritisStudies 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 146 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Jean-Paul Makhzoum, Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
- Investigators
- Jean-Paul Makhzoum, Study chair, CISSS du Nord-de-l'ile de Montreal
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05703763
- Sponsor's protocol ID
- 2020-1890
- Acronym
- ATOM-GCA
- Status last verified
- Oct 2026
- First submitted
- 17 Jan 2023
- Last updated
- 21 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Zarka F, Rheaume M, Belhocine M, Goulet M, Febrer G, Mansour AM, Troyanov Y, Starnino T, Meunier RS, Chagnon I, Routhier N, Benard V, Ducharme-Benard S, Ross C, Makhzoum JP. Colour Doppler ultrasound and the giant cell arteritis probability score for the diagnosis of giant cell arteritis: a Canadian single-centre experience. Rheumatol Adv Pract. 2021 Nov 10;5(3):rkab083. doi: 10.1093/rap/rkab083. eCollection 2021.
PubMed 34859177Baalbaki H, Jalaledin D, Lachance C, Febrer G, Rheaume M, Makhzoum JP. Characterization of visual manifestations and identification of risk factors for permanent vision loss in patients with giant cell arteritis. Clin Rheumatol. 2021 Aug;40(8):3207-3217. doi: 10.1007/s10067-021-05643-5. Epub 2021 Feb 12.
PubMed 33580374
Study at a glance
From the registry record, last updated by the sponsor on 21 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Applanation Tonometry in Giant Cell Arteritis Pilot
- ClinicalTrials.gov ID
- NCT05703763
- Acronym / sponsor ID
- ATOM-GCA / 2020-1890
- Conditions
- Giant Cell Arteritis
- Keywords
- diagnosis
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 146 participants (estimated)
- Lead sponsor
- Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de MontrealUniversity, hospital or other
- Study start
- 30 Jul 2025 (actual)
- Primary completion
- Mar 2027 (estimated)
- Study completion
- Jul 2027 (estimated)
- First posted
- 30 Jan 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The Applanation Tonometry in Giant Cell Arteritis (ATOM-GCA) study will answer the following questions:
- How does PWV, measured by applanation tonometry of temporal arteries, differ between patients with and without a final diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?
- What is the diagnostic accuracy and positivity cutoff of the PWV, measured by applanation tonometry, in detecting:
- A clinical diagnosis of GCA (based on pre-defined criteria 6 months after inclusion)?
- Inflammation of temporal arteries on high-resolution ultrasound?
- What is the acceptability and adherence of repeat applanation tonometry during the follow-up period in patients with GCA?
Detailed description
ATOM-GCA is a single-center, cross-sectional vanguard study.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| GCA group | – | Diagnostic Test: Applanation tonometry, Diagnostic Test: Standardized GCA assessment, Diagnostic Test: Repeat applanation tonometry (optional)Definite confirmation of GCA will occur 6 months after study inclusion, following the phone follow-up, and will require all the following features: 1) initial symptoms and clinical evolution consistent with GCA; 2) at least one positive test for cranial GCA (ultrasound of temporal arteries, temporal artery biopsy, cranial MRI, cranial PET); and 3) satisfies the 2022 ACR-EULAR classification criteria for GCA. |
| Non-GCA group | – | Diagnostic Test: Applanation tonometry, Diagnostic Test: Standardized GCA assessmentParticipants who do not meet the criteria (above) for GCA at month 6. |
Who may qualify
- Ages
- 50 to 99 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Consecutive patients referred for suspected new-onset GCA
Key inclusion criteria (5 listed)
- Age > 50 years.
- Referral for suspected, new-onset GCA.
- Ability to understand and willingness to sign an informed consent form.
- Willingness to comply with study visits and procedures.
Key exclusion criteria (7 listed)
- Referral for a suspected GCA relapse.
- Current use of systemic glucocorticoids, with the following duration at the baseline visit:
- Current use of any conventional or biologic immunosuppressive therapy.
- Temporal artery biopsy prior to the study visit.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Applanation tonometryApplanation tonometry will be used to measure arterial stiffness in these segments, bilaterally: * Superficial temporal artery to frontal temporal artery * Common carotid artery to superficial temporal artery | Diagnostic test | GCA group, Non-GCA group |
| Standardized GCA assessmentClinical assessment, blood test review, high-resolution temporal artery ultrasound using a 24mHz probe. | Diagnostic test | GCA group, Non-GCA group |
| Repeat applanation tonometry (optional)Repeat index test at month 6 and at disease relapse. | Diagnostic test | GCA group |
Primary outcome
PWV in patients with and without GCA
Time frame: Baseline
The primary outcome of ATOM-GCA is to compare the mean PWV in patients with GCA to the mean PWV in individuals without GCA. Final confirmation of GCA will be determined 6 months after study inclusion. This analysis will establish whether the PWV differs in GCA. Additionally, we will explore the optimal PWV cutoff and evaluate its diagnostic performance to confirm a final diagnosis of GCA at 6 months.
1 secondary outcome
Diagnostic performance of the PWV
Time frame: Baseline
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Oct 2026.
- Background: PubMed 34859177Zarka F, Rheaume M, Belhocine M, Goulet M, Febrer G, Mansour AM, Troyanov Y, Starnino T, Meunier RS, Chagnon I, Routhier N, Benard V, Ducharme-Benard S, Ross C, Makhzoum JP. Colour Doppler ultrasound and the giant cell arteritis probability score for the diagnosis of giant cell arteritis: a Canadian single-centre experience. Rheumatol Adv Pract. 2021 Nov 10;5(3):rkab083. doi: 10.1093/rap/rkab083. eCollection 2021.
- Background: PubMed 33580374Baalbaki H, Jalaledin D, Lachance C, Febrer G, Rheaume M, Makhzoum JP. Characterization of visual manifestations and identification of risk factors for permanent vision loss in patients with giant cell arteritis. Clin Rheumatol. 2021 Aug;40(8):3207-3217. doi: 10.1007/s10067-021-05643-5. Epub 2021 Feb 12.
- Vasculitis Clinic - University of MontrealLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jean-Paul Makhzoum study chair
CISSS du Nord-de-l'ile de Montreal
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Giant Cell Arteritis, run by Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 21 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
PWV in patients with and without GCA (time frame: Baseline). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05703763, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Oct 2026.