Exploring the Novel Value of PSMA PET in Sjögren's Syndrome: Integrated Analysis With Established FAPI PET Imaging

NCT07324733 | Recruiting

• 1 other identifier: PUMCH-PSS-PSMA
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Primary Sjögren's syndrome (pSS) is a chronic autoimmune exocrinopathy characterized by lymphocytic infiltration, progressive destruction of salivary gland acini, and varying degrees of functional impairment and fibrosis. Conventional imaging provides limited ability to simultaneously evaluate glandular function and inflammatory activity, leading to challenges in disease staging and treatment decision-making. This study explores a conceptual dual-tracer imaging framework using PSMA PET and FAPI PET to delineate complementary biological processes in pSS.

Conditions

Primary Sjögren Syndrome; PET

Outcome Measures

Primary Outcomes (1)

• Difference in Salivary Gland PSMA Uptake Across Groups

  Quantitative comparison of PSMA PET uptake parameters (SUVmax, SUVmean) of the parotid glands among three groups: pSS patients, individuals with normal salivary glands, and prostate cancer patients.

  Baseline

Secondary Outcomes (3)

• Multiglandular PSMA Uptake Comparison

  Baseline

• Correlation Between PSMA Uptake and Clinical Indicators

  Baseline

• Quantitative and Spatial Relationship Between PSMA and FAPI Uptake Definition

  Baseline

Study Arms (2)

pSS Dual-Tracer Imaging Arm (PSMA + FAPI PET)

EXPERIMENTAL

This arm includes patients diagnosed with primary Sjögren's syndrome. All participants undergo both PSMA PET and FAPI PET imaging. The PSMA PET scan is used to assess the functional integrity of salivary gland acinar cells, while the FAPI PET scan evaluates inflammatory and fibroblast activity within the same glands. The purpose of this arm is to characterize the functional-inflammatory relationship in pSS and to develop the combined PSMA/FAPI Index for disease staging and activity assessment.

Diagnostic Test: ⁶⁸Ga-PSMA PET/CT; Diagnostic Test: ⁶⁸Ga-FAPI PET/CT

Prostate Cancer PSMA-Only Comparator Arm

ACTIVE COMPARATOR

This arm consists of patients with prostate cancer who undergo PSMA PET imaging only, representing a population with preserved or physiologic salivary gland PSMA uptake. These scans serve as a reference group for establishing normal or baseline PSMA expression in salivary glands. This comparator arm allows differentiation between disease-related PSMA reduction in pSS and normal tracer distribution observed in patients without salivary gland pathology.

Diagnostic Test: ⁶⁸Ga-PSMA PET/CT

Interventions

⁶⁸Ga-PSMA PET/CT DIAGNOSTIC_TEST

PSMA PET imaging performed for clinical evaluation in prostate cancer patients, used as a comparator for physiologic salivary gland PSMA uptake.

Prostate Cancer PSMA-Only Comparator Arm; pSS Dual-Tracer Imaging Arm (PSMA + FAPI PET)

⁶⁸Ga-FAPI PET/CT DIAGNOSTIC_TEST

FAPI PET imaging to assess inflammatory activity (FAPI) in patients with primary Sjögren's syndrome.

pSS Dual-Tracer Imaging Arm (PSMA + FAPI PET)

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-80 years;
• Fulfillment of the 2016 ACR-EULAR Classification Criteria for pSS at enrollment. OR diagnosis of a solid tumor scheduled for FAPI PET imaging

You may not qualify if:

• Combined with tumors or other connective tissue diseases (for SS group);
• Patients who are currently using hormones/biological agents (for both groups)；
• Pregnancy or lactation

Sponsors & Collaborators

• Peking Union Medical College Hospital: lead

Study Sites (1)

Peking Union Medical College Hospital

Beijing, China

RECRUITING

Central Study Contacts

Zhaohui Zhu, MD

CONTACT

13611093752; 13611093752@163.com

Jiarou Wang, MD

CONTACT

13628477019; ChristinaWang97@163.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 24, 2025
• First Posted: January 7, 2026
• Study Start: September 1, 2025
• Primary Completion: January 30, 2026
• Study Completion (Estimated): May 30, 2026
• Last Updated: January 7, 2026

Record last verified: 2025-12

Locations

CN (1)