68Ga-FAPi-46 PET/CT Scan in Imaging Patients With Sarcoma

July 16, 2026 updated by: Jonsson Comprehensive Cancer Center

PET Biodistribution Study of 68Ga-FAPI-46 in Patients With Sarcoma: An Exploratory Biodistribution Study With Histopathology Validation

This early phase I trial studies an imaging technique called 68Ga-FAPi-46 PET/CT to determine where and to which degree the FAPI tracer (68Ga-FAPi-46) accumulates in normal and cancer tissues in patients with sarcoma. PET is an established imaging technique that utilizes small amounts of radioactivity attached to very minimal amounts of tracer, in the case of this research, 68Ga-FAPi. Because some cancers take up 68Ga-FAPi it can be seen with PET. CT utilizes x-rays that traverse body from the outside. CT images provide an exact outline of organs and potential inflammatory tissue where it occurs in patient's body.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

PRIMARY OBJECTIVE:

I. To define the biodistribution of gallium Ga 68 fibroblast activation protein inhibitor (FAPi)-46 (68Ga-FAPi-46) in normal and cancer tissues of patients with sarcoma with histopathology validation.

SECONDARY OBJECTIVES:

I. To evaluate whether 68Ga-FAPi-46 accumulation observed by positron emission tomography (PET) reflects geography, extent and degree of FAP expression determined by immuno-histochemistry (IHC).

II. To assess the 68Ga-FAPI-46 biodistribution correlation with fludeoxyglucose F-18 (18F-FDG) biodistribution and to define the frequency of the following phenotypes (FAP positive [+]/ FDG+, FAP negative [-]/ FDG+, FAP+/ FDG-, FAP-/ FDG-).

III. 3. To determine FAP expression profile and identify activating and loss of function mutations and gene rearrangement in available tumor tissue samples from patients with localized or metastatic sarcoma using RNA sequencing

OUTLINE:

Patients receive 68Ga-FAPi-46 intravenously (IV), and then undergo PET/computed tomography (CT) over 20-90 minutes. On another day, patients receive 18F-FDG and then undergo PET/computed tomography (CT) according to standard of care procedures (if applicable).

Study Type

Interventional

Enrollment (Actual)

18

Phase

  • Early Phase 1

Contacts and Locations

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

Study Locations

  • United States
    • California
      • Los Angeles, California, United States, 90095
        • UCLA / Jonsson Comprehensive Cancer Center

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

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients who are scheduled to undergo surgical excision or biopsy of a suspected sarcoma primary, or a suspected recurrent or metastatic lesion.
  • Patients who are ≥ 18 years old at the time of the radiotracer administration.
  • Patients who can provide written informed consent.
  • Patients who are able to remain still for duration of imaging procedures (up to one hour for each).

Exclusion Criteria:

  • Patient is pregnant or nursing.
  • Patients with any new cancer therapy between the baseline 18F-FDG PET/CT and the investigational FAPI PET/CT
  • Patient has underlying disease which, based on the judgment of the investigator, might interfere with the collection of high quality data.

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: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Diagnostic (68Ga-FAPI-46 PET/CT)
Patients receive 68Ga-FAPi-46 intravenously (IV), and then undergo PET/computed tomography (CT) over 20-90 minutes. On another day, patients receive 18F-FDG and then undergo PET/computed tomography (CT) according to standard of care procedures (if applicable).
Procedure: Computed Tomography
Undergo PET/CT
Other Names:
  • CT
  • CAT
  • CAT Scan
  • Computerized Axial Tomography
  • Computerized Tomography
  • CT Scan
  • tomography
Procedure: Positron Emission Tomography
Undergo PET/CT
Other Names:
  • Medical Imaging, Positron Emission Tomography
  • PET
  • PET Scan
  • Positron Emission Tomography Scan
  • Positron-Emission Tomography
  • proton magnetic resonance spectroscopic imaging
Drug: Gallium Ga 68 FAPi-46
Given IV
Other Names:
  • 68Ga-FAPi-46
  • Gallium-68-FAPi-46
Radiation: 18F-FDG
Given IV
Other Names:
  • 18F-fluorodeoxyglucose

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Biodistribution of gallium Ga 68 fibroblast activation protein inhibitor (FAPi)-46 (68Ga-FAPi-46) in normal and cancer tissues
Time Frame: At 20-90 minutes after injection
Will be quantified by mean and maximum standardized uptake values (SUVmean and SUVmax).
At 20-90 minutes after injection

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
68Ga-FAPi-46 accumulation observed by positron emission tomography (PET)/computed tomography (CT)
Time Frame: Up to year 2
Will be correlated with and validated by FAP expression in surgically removed or biopsy derived tumor tissue.
Up to year 2
Frequency of the following phenotypes (FAP positive [+]/ fludeoxyglucose [FDG]+, FAP negative [-]/ FDG+, FAP+/ FDG-, FAP-/ FDG-)
Time Frame: Up to year 2
To assess the 68Ga-FAPI-46 biodistribution correlation with 18F-FDG biodistribution and to define the frequency of the following phenotypes (FAP+/ FDG+, FAP-/ FDG+, FAP+/ FDG-, FAP-/ FDG-)
Up to year 2

Collaborators and Investigators

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

Sponsor

Jonsson Comprehensive Cancer Center

Collaborators

National Cancer Institute (NCI)

Investigators

  • Principal Investigator: Jeremie Calais, MD, UCLA / Jonsson Comprehensive Cancer Center

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)

September 8, 2020

Primary Completion (Estimated)

December 2, 2026

Study Completion (Estimated)

December 2, 2027

Study Registration Dates

First Submitted

June 30, 2020

First Submitted That Met QC Criteria

June 30, 2020

First Posted (Actual)

July 7, 2020

Study Record Updates

Last Update Posted (Actual)

July 17, 2026

Last Update Submitted That Met QC Criteria

July 16, 2026

Last Verified

August 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 20-000623 (UCLA / Jonsson Comprehensive Cancer Center)
  • NCI-2020-03767 (Registry Identifier: CTRP (Clinical Trial Reporting Program))

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

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.

Subscribe