Clinical trial NCT05604482: CXCR4-PET/CT for Diagnosing Giant Cell Arteritis
Official title: Detection of Disease Activity in Giant Cell Arteritis Using CXCR4-PET/CT
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Vasculitis
Diagnoses Disease
Keywords: Vasculitis
LV-GCA
Giant cell arteritis
FDG-PET
Imaging
CXCR4
Lead sponsor: Wuerzburg University Hospital
Sponsor class: OTHER
First posted: 2022-11-03
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: Giant cell arteritis (GCA) is the most common vasculitis in the elderly. Accurate diagnosis is of utmost importance in order to then initiate the necessary immunosuppressive therapy. For large-vessel GCA (LV-GCA) involving the aorta and its branches, FDG-PET/CT is the standard in imaging for diagnosis and is recommended by the guidelines. However, this only indirectly visualizes inflammation through vessel wall uptake of glucose. A new PET tracer, 68Ga-pentixafor, is used to visualize the chemokine receptor CXCR4. This receptor is expressed by cells of the immune system. In the context of inflammatory processes, upregulation of CXCL12, the ligand of CXCR4, occurs in affected tissues. The chemotactic effect of this ligand leads to the immigration of CXCR4-positive inflammatory cells into the inflamed area, which can be visualized by PET using the CXCR4-specific tracer 68Ga-Pentixafor. The value of CXCR4-PET should therefore be tested in the context of LV-GCA. This study tests the benefit of CXCR4 in therapy-naïve patients with suspected LV-GCA. For this purpose, patients will receive a FDG-PET and a CXCR4-PET for direct comparison. This is an imaging-only study. Therapy will not be affected by the study. The study is single-arm and not blinded.


Eligibility criteria: Inclusion Criteria:

* New diagnosis of GCA within 5 days of diagnosis or initiation or intensification of therapy.
* Evidence of inflammatory activity based on clinical parameters, elevated serologic markers of inflammation (CRP \> 1.0 mg/dl), or a positive imaging finding on vasculitis MRI, CCDS, or FDG-PET/CT
* Ability of the patient to provide information
* Exclusion of contraindications for the performance of a PET/CT examination (see below)

Exclusion Criteria:

* Contraindications for the performance of a PET CT examination
* Pregnancy
* Allergies
* Lack of capacity of the patient to give informed consent

Primary outcomes:
measure: Maximum measurable tracer activity on 68Ga-Pentixafor PET/CT in the area of blood vessels in active GCA
timeFrame: 2 years
Secondary outcomes:
measure: Correlation with clinical parameters
timeFrame: 2 years
measure: Correlation with blood leukocyte count
timeFrame: 2 years
measure: Comparison to other imaging modalities
timeFrame: 2 years
Other outcomes:
Locations:
city: Würzburg
country: Germany
facility: Departement of Internal Medicine II, Rheumatology/Clinical Immunology
state: Bayern
Study officials:
affiliation: University Hospital Würzburg Oberdürrbacherstrasse 6, 97080 Würzburg, Germany,
name: Rudolf A Werner, MD
role: STUDY_CHAIR
References: