Clinical Applications of FAPI PET in Solid Tumors

August 17, 2026 updated by: Ruijin Hospital

Clinical Applications of Novel FAPI PET in Diverse Solid Tumors

The study systematically evaluates the diagnostic performance of FAPI-RuiJ and FAPI-04 PET/CT or PET/MR in various solid tumor types, and is expected to provide a novel molecular imaging tool for early lesion detection, accurate staging, and recurrence surveillance in patients with solid tumors.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

This prospective study is designed to evaluate and compare the PET/CT or PET/MR imaging characteristics of two fibroblast activation protein (FAP)-targeted tracers-the novel tracer FAPI-RuiJ and the reference tracer FAPI-04-across a diverse range of solid tumors. All enrolled patients will undergo paired PET imaging with both FAPI-RuiJ and FAPI-04. For each tracer, semi-quantitative uptake parameters (including SUVmax, SUVmean, SUVpeak, tumor-to-background ratio [TBR]）will be measured and compared. Biodistribution characteristics of FAPI-RuiJ in normal organs will be assessed to determine its in vivo metabolic profile. Using histopathology or imaging follow-up as the reference standard, the diagnostic performance of FAPI-RuiJ PET will be compared with that of FAPI-04 PET, with evaluation metrics including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver operating characteristic curve (AUC). Correlation analyses will be performed between PET parameters and clinicopathological characteristics, including tumor markers, pathological subtype, and immunohistochemical markers.The study is expected to provide a novel molecular imaging tool to support early lesion detection, accurate staging, and recurrence surveillance in patients with solid tumors.

Study Type

Interventional

Enrollment (Estimated)

200

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • China
      • Shanghai, China
        • Recruiting
        • Ruijin Hospital, Shanghai Jiao Tong University School of Medicine
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Age ≥ 18 years and ≤ 80 years, regardless of gender.
  2. Participants with suspected, confirmed, or suspected recurrent solid tumors.
  3. Participants who agree to participate in this clinical trial and provide written informed consent.
  4. Participants with good compliance, who commit to adhering to the study procedures and cooperate with the full study process.
  5. No plans for pregnancy within 6 months.

Exclusion Criteria:

  1. Patients with severe medical conditions that, in the investigator's opinion, make them unsuitable for participation in this clinical study, including but not limited to: severe cardiopulmonary insufficiency, severe bone marrow suppression, and severe hepatic or renal insufficiency.
  2. Patients with claustrophobia, severe psychiatric symptoms, or impaired consciousness that precludes cooperation with the examination procedures.
  3. Patients who have received any anti-tumor therapy during the interval between the two PET imaging sessions.
  4. Pregnant or breastfeeding women.
  5. Patients with poor compliance.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Participants will undergo FAPI-RuiJ PET/CT or PET/MR, followed by FAPI-04 imaging on a separate day
Participants will undergo paired PET/CT or PET/MR imaging sequentially, with FAPI-RuiJ administered first and FAPI-04 on a separate day (interval: 1-7 days). For each tracer, a single intravenous injection will be given, followed by whole-body image acquisition at a standardized post-injection time. All images will be independently reviewed by two blinded nuclear medicine physicians. Histopathology or imaging follow-up serves as the reference standard.
Diagnostic test: FAPI-RuiJ
A novel FAP-targeted radiotracer for PET/CT or PET/MR imaging; administered intravenously.
Diagnostic test: FAPI-04
A FAP-targeted radiotracer for PET/CT or PET/MR imaging; administered intravenously.
Experimental: Participants will undergo FAPI-04 PET/CT or PET/MR, followed by FAPI-RuiJ imaging on a separate day
Participants will undergo paired PET/CT or PET/MR imaging sequentially, with FAPI-04 administered first and FAPI-RuiJ on a separate day (interval: 1-7 days). For each tracer, a single intravenous injection will be given, followed by whole-body image acquisition at a standardized post-injection time. All images will be independently reviewed by two blinded nuclear medicine physicians. Histopathology or imaging follow-up serves as the reference standard.
Diagnostic test: FAPI-RuiJ
A novel FAP-targeted radiotracer for PET/CT or PET/MR imaging; administered intravenously.
Diagnostic test: FAPI-04
A FAP-targeted radiotracer for PET/CT or PET/MR imaging; administered intravenously.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Diagnostic sensitivity, specificity, PPV, NPV, and accuracy of FAPI-RuiJ PET versus FAPI-04 PET
Time Frame: Through study completion, an average of 3 years
Overall and tumor type-specific diagnostic performance in solid tumors, using histopathology or imaging follow-up as the reference standard.
Through study completion, an average of 3 years
AUC of FAPI-RuiJ PET versus FAPI-04 PET
Time Frame: Through study completion, an average of 3 years
Overall and tumor type-specific AUC comparison between the two tracers in solid tumors, using histopathology or imaging follow-up as the reference standard.
Through study completion, an average of 3 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Comparison of SUVmax, SUVmean, and SUVpeak of FAPI-RuiJ PET versus FAPI-04 PET in solid tumor lesions
Time Frame: At the time of PET/CT scan
Semi-quantitative comparison of standardized uptake value (SUV) parameters (SUVmax, SUVmean, and SUVpeak) between the two tracers in solid tumor lesions.
At the time of PET/CT scan
Comparison of TBR of FAPI-RuiJ PET versus FAPI-04 PET in solid tumor lesions
Time Frame: At the time of PET/CT scan
Semi-quantitative comparison of TBR between the two tracers in solid tumor lesions. TBR is calculated as the ratio of tumor SUVmax to background SUVmean.
At the time of PET/CT scan
Biodistribution characteristics of FAPI-RuiJ PET in normal organs
Time Frame: At the time of PET/CT scan
Quantitative assessment of FAPI-RuiJ tracer biodistribution in major normal organs (including brain, submandibular gland, thyroid, lung, descending aorta, heart, liver, pancreas, stomach, spleen, kidney, bone, muscle, small intestine, gallbladder) measured by SUVmean and SUVmax on PET/CT images using ROI-based analysis.
At the time of PET/CT scan
Correlation between FAPI-RuiJ PET semi-quantitative parameters and clinicopathological characteristics in solid tumors
Time Frame: Through study completion, an average of 3 years
Correlation analysis between FAPI-RuiJ PET semi-quantitative uptake parameters (including SUVmax, SUVmean, SUVpeak, TBR and clinicopathological characteristics, including tumor markers (e.g., CEA, CA19-9, AFP, etc.), pathological subtype, and immunohistochemical markers (e.g., Ki-67, PD-L1, EGFR, etc.). Correlations will be assessed using Spearman's rank correlation coefficient (ρ), with statistical significance set at p < 0.05.
Through study completion, an average of 3 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Ruijin Hospital

Investigators

  • Principal Investigator: Biao Li, Ruijin Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 2, 2026

Primary Completion (Estimated)

March 31, 2029

Study Completion (Estimated)

March 31, 2029

Study Registration Dates

First Submitted

July 26, 2026

First Submitted That Met QC Criteria

August 17, 2026

First Posted (Actual)

August 20, 2026

Study Record Updates

Last Update Posted (Actual)

August 20, 2026

Last Update Submitted That Met QC Criteria

August 17, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • 2026 CER 311

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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