A novel fibroblast imaging biomarker and ultrahigh resolution PET to improve the diagnosis and follow-up of giant cell arteritis

Overview

Sponsor-declared trial summary

Key facts

Sponsor

UZ Leuven

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Cardiovascular Diseases [C14], Diseases [C] - Immune System Diseases [C20]

Trial duration

4 May 2026 → ongoing

Decision date (initial)

2026-02-09

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Fund Stéphanie Willems managed by the King Baudouin Foundation.

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Diagnosis

1. Demonstrate the ability of NX PET/CT to assess active arteritis of the ophthalmic artery.
2. Demonstrate that the diagnostic performance of FAPI PET/CT is at least equivalent to the current gold standard, FDG PET (non-inferiority study with non-inferiority limit 15%).
3. Demonstrate the ability of FAPI PET/CT to identify chronic pathological fibroblast activation.
4. To unravel the role of FAP in the pathogenesis of GCA using single nuclei RNA sequencing on temporal artery biopsies, obtained from patients with GCA.
5. Primary objectives UHR NeuroEXPLORER PET : see Master Protocol EUDAMED_ CIV-25-06-053398

Secondary objectives 1

1. 1. To distinguish GCA from non-GCA causes in patients presenting with vision loss. 2. To evaluate the evolution of FAPI and FDG uptake from active disease to remission. 3. To identify other import cell types in the pathogenesis of GCA using single nuclei RNA sequencing. 4. Secondary objectives UHR NeuroEXPLORER PET MDR part : see Master Protocol EUDAMED_ CIV-25-06-053398

Conditions and MedDRA coding

Giant Cell Arteritis

Regulatory references

Plan to share IPD

No

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 1

1. Participants eligible for inclusion in this Trial must meet all of the following criteria: - Voluntary written informed consent of the participant or their legally authorized representative has been obtained prior to any screening procedures - At least 18 years of age at the time of signing the Informed Consent Form (ICF) - Female subjects should be (a) post-menopausal, or (b) surgically sterile, or (c) using effective contraceptive with negative pregnancy test. - Patients with a high clinical suspicion of GCA according to a clinical physician with ample experience. - Treatment with glucocorticosteroids has not commenced. However, if urgent ischemic symptoms arise, treatment with glucocorticoids will be initiated and both PET/CT scans will be performed within the first 3 days of therapy.

Exclusion criteria 1

1. Participants eligible for this Investigation must not meet any of the following criteria: - Treatment with oral glucocorticoids already commenced. However, if urgent ischemic symptoms arise, treatment with glucocorticoids will be initiated and both PET/CT scans will be performed within the first 3 days of therapy. - Participant is mentally or legally incapacitated, doesn’t understand the study design or is not willing or capable to undergo all study-specific procedures. - Any disorder or condition, which in the Investigator’s opinion might jeopardise the participant’s safety or compliance with the protocol. - Any prior or concomitant treatment(s) that might jeopardise the participant’s safety or that would compromise the integrity of the Trial. - Female who is pregnant (urinary hCG test will be performed in every WOCBP), breast-feeding or intends to become pregnant or is of child-bearing potential and not using an adequate, highly effective contraceptive (with a relatively high Pearl Index: natural methods, minipill outside postpartum period, spermicides or condoms in monotherapy or no usage of contraception when sexually active are not accepted). - Participation in an interventional Trial with an investigational medicinal product (IMP) or device when the trial designs are not considered compatible by the study team. - Participation in a clinical scientific study in the last 12 months with a radiation exposure caused by the experimental procedures greater than 1 mSv. - Participant has a known hypersensitivity to [ 18F]AlF-FAPI-74 or the used excipients

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Ability to visualize activate arteritis of the ophthalmic artery. Diagnostic accuracy (AUC – combined sensitivity and specifity) of FDG and FAPI PET for diagnosing GCA. Ability to visualize to identify chronic pathological fibroblast activation on FAPI PET. Demontsrate a correlation between FAP+ fibroblast cell state and FAPI PET parameters at clinical diagnosis and remission. Additional primary endpoints related to the clinical investigational NeuroEXPLORER device : See Master Protocol

Secondary endpoints 1

1. To distinguish GCA from non-GCA causes in patients presenting with vision loss. . To evaluate the evolution of FAPI and FDG uptake from active disease to remission. To identify other import cell types in the pathogenesis of GCA using single nuclei RNA sequencing. Additional secondary endpoints related to the clinical investigational NeuroEXPLORER device: See Master Protocol EUDAMED_ CIV-25-06-053398.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

UZ Leuven

Sponsor organisation

UZ Leuven

Address

Herestraat 49

City

Leuven

Postcode

3000

Country

Belgium

Scientific contact point

Organisation

UZ Leuven

Contact name

Koen Van Laere

Public contact point

Organisation

UZ Leuven

Contact name

Koen Van Laere

Locations

1 EU/EEA country · 1 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 10 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

1 submissions — initial application plus substantial / non-substantial modifications