The PET Imaging of Giant Cell and Takayasu Arteritis Study
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 入组人数
- 27
- 试验地点
- 2
- 主要终点
- Diagnostic accuracy of SST2 PET-MRI for LVV
研究概览
简要总结
While 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging is often included in the diagnostic work-up of patients with large-vessel vasculitis (LVV), 18F-FDG lacks specificity for inflammatory cells and has limited ability to track therapy response. Moreover, high background 18F-FDG uptake in the brain and myocardium largely precludes imaging temporal arteritis in giant-cell arteritis (GCA) and coronary artery involvement in Takayasu arteritis respectively. These limitations of 18F-FDG for imaging LVV highlight important unmet clinical needs, which might be overcome by using a somatostatin receptor subtype-2 (SST2) PET tracer.
详细描述
Up-regulation of SST2 in activated macrophages represents a novel imaging target for measuring vascular inflammation, which has been previously examined in atherosclerosis using 68Ga-DOTATATE. To test the hypothesis that SST2 PET imaging can accurately identify LVV, patients with active GCA or Takayasu arteritis will undergo vascular 68Ga-DOTATATE or 18F-fluoroethyltriazole-(Tyr3)-octreotate (FETO) PET-MRI at baseline, with repeat imaging after 6 months of treatment. A group of individuals with LVV in clinical remission will also undergo SST2 PET imaging. Data from patients with clinically inactive disease will serve to confirm tracer specificity for active disease, as well as signal reproducibility. 18F-FETO is an alternative SST2 tracer to 68Ga-DOTATATE; the longer half-life and shorter positron range of 18F compared to 68Ga may offer several advantages, including wider tracer availability and improved spatial resolution when imaging small arteries. All patients will also undergo 18F-FDG imaging before treatment, where clinically indicated.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 99 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Male or female participants >18 years old
- •Able to give written, informed consent and to lie flat
- •New clinical diagnosis or acute flare of LVV (Giant-cell arteritis or Takayasu's arteritis) within ~1 week of treatment initiation, and
- •Clinical indication for 18F-FDG PET-CT scan determined by the referring physician, or
- •Undergoing surgery for LVV, or
- •Diagnosis of LVV in remission
排除标准
- •Women of child bearing potential not using adequate contraception
- •Contra-indication to MRI scanning
- •Contrast allergy or contrast-nephropathy
- •Chronic kidney disease (eGFR <30 mL/min/1.73 m2)
- •Any medical condition, in the opinion of the investigator, that prevents the participant from lying flat during scanning, or from participating in the study
- •History of recent malignancy deemed relevant to the study by the investigator
结局指标
主要结局
Diagnostic accuracy of SST2 PET-MRI for LVV
时间窗: Baseline
To determine the diagnostic accuracy of SST2 PET-MRI for LVV, with the clinically adjudicated diagnosis as the gold-standard.
次要结局
- Comparison with biochemical markers of disease severity(Baseline and 6 months)
- Treatment response(6 months)
- Active versus inactive disease(Baseline)
- Comparison with clinical measures of disease severity(Baseline and 6 months)
- Comparison of SST2 PET tracers(Baseline and 6 months)
研究者
Jason Tarkin
Wellcome Clinical Research Career Development Fellow
University of Cambridge