Fibroblast Activating Protein Inhibitor PET Imaging in Lupus Nephritis

Study Overview
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Brief Summary
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Abnormal high expression of fibroblast activating protein (FAP) has been found in inflammatory reactions and benign fibrosis tissue. Autoimmune nephropathy such as lupus nephritis (LN) can lead to tubular atrophy and excessive deposition of extracellular matrix, which may be accompanied by abnormally increased expression of activated FAP in kidney tissue, and lead to renal fibrosis and long-term renal failure. This makes 68Ga-labeled FAP inhibitor (FAPI) positron emission tomography (PET) imaging the potential to early assess disease severity, predict disease progress and aid treatment planning in patients with LN. Compared to renal pathological puncture, 68Ga-FAPI PET is a new tool for non-invasive, repeatable assessment of renal fibrotic activation.

Official Title
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Fibroblast Activating Protein Inhibitor PET Imaging for Molecular Assessment of Fibroblast Activation and Risk Evaluation in Patients With Lupus Nephritis

Conditions
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Lupus Nephritis

Intervention / Treatment
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* Diagnostic Test: 68Ga-FAPI-04 PET


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be between 18-80 years old; Confirmed SLE: meet the 2019 EULAR/ACR classification standards; There are signs of renal involvement and indications for renal puncture: proteinuria> 0.5g/24 hours (or urine protein creatine ratio (UPCR) >500mg/g), unexplained decrease of glomerular filtration rate (GFR) Exclusion Criteria: The pathology of renal puncture is not consistent with lupus nephritis; Previous history of other kidney diseases; There are contraindications to renal puncture: (1) obvious bleeding tendency, (2) severe hypertension, (3) psychosis or non-cooperative patients, (4) isolated kidney, (5) small kidney; History of malignant tumors within 5 years.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LN Patients group<br> | Diagnostic Test: 68Ga-FAPI-04 PET<br>* Activation of renal fibroblast is quantified using 68Ga-FAPI-04 PET in patients with LN.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Renal FAP expression level | Quantitative assessment of renal fibroblast activation on FAPI PET image | Baseline | 
| Renal FAP expression level | Quantitative assessment of renal fibroblast activation on FAPI PET image | 6 months after baseline | 
| Renal FAP expression level | Quantitative assessment of renal fibroblast activation on FAPI PET image | 12 months after baseline | 
| Renal FAP expression level | Quantitative assessment of renal fibroblast activation on FAPI PET image | 24 months after baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Renal fibrosis score | It's an immunohistochemical staining-based score after renal puncture. Higher score means a worse outcome. | Baseline | 
| Chronic activity score | It's an immunohistochemical staining-based scores after renal puncture. Higher score means a worse outcome. | Baseline |