ClinicalTrials.gg
Not yet recruitingNCT07705074FAPIPETUpdated Jul 15, 2026

FAPI PET Imaging - An Exploratory Study

A Phase 1/2 interventional study of [18F]FAPI-74 PET/CT in Thyroid Pathology, Head and Neck Cancer (H&N) and Sinonasal Tract Tumor, sponsored by Martin Huellner. Not yet recruiting at 5 sites in Switzerland. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-15.

Primary conditionThyroid NeoplasmsRegistry: Head and Neck NeoplasmsReclassifiedWhy we changed it
Registry
Head and Neck Neoplasms — the first condition term the registry derived for this study.
ClinicalTrials.gg
Thyroid Neoplasms
Why
  1. The study's listed conditions name Thyroid Neoplasms, a narrower term within Head and Neck Neoplasms.
Confidence
High: the new condition is named in the study's own listed conditions. Of 351 hand-checked studies reclassified this way, 68% were exactly right and 84% in the right disease family; the registry's first term was right for 5% (measured 2026-10-21). How we classify →
Wrong?
Tell us the study's main condition →

Sponsored by Martin Huellner · Phase 1/2, Interventional, and Diagnostic

Phase
Phase 1/2
Study type
Interventional
Enrollment
770
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This study is testing a new imaging tracer called [18F]FAPI-74 with PET scans. Researchers want to find out how well this tracer shows certain diseases in the body, including several types of cancer and some non-cancer conditions like fibrosis and sarcoidosis.

[18F]FAPI-74 attaches to a protein found on cells that are active in tumors and areas of scarring or inflammation. This may help doctors see these areas more clearly than with imaging methods used today, especially in diseases where current scans do not work well.

People who join this study will get one injection of the tracer into a vein, then have one PET/CT or PET/MR scan. This takes about 2 hours in total. Researchers will compare the results with imaging the participant already had as part of their regular care, such as other PET scans, CT, or MRI. No extra treatment is given, and no other visits are needed.

The study will take place at 5 hospitals in Switzerland and plans to include about 770 adults with a confirmed or suspected diagnosis of one of the conditions being studied. The main goal is to see how clearly the tracer shows up on the scan. Researchers will also look at whether this new scan changes how confident doctors feel about a diagnosis, or changes the patient's treatment plan.

Read the detailed description

Background and Rationale:

Fibroblast Activation Protein (FAP) is highly expressed in cancer-associated fibroblasts and in a range of fibrotic and inflammatory diseases. [18F]FAPI-74 is a novel PET radiotracer that binds selectively to FAP, enabling visualization of fibroblast activity. Early clinical studies have demonstrated promising tumour-to-background contrast, superior detectability compared with FDG in several tumours, and potential value in diseases where no adequate PET tracers exist. This multicentre study aims to systematically evaluate biodistribution, uptake patterns, and diagnostic usefulness of [18F]FAPI-74 across a broad spectrum of oncologic and non-oncologic indications.

Study Design:

This is an open-label, non-randomized, single-arm, exploratory diagnostic study conducted at five Swiss centres. Each participant undergoes a single administration of [18F]FAPI-74 followed by one PET/CT or PET/MR scan. No therapeutic interventions, follow-up visits, or repeat tracer administrations are planned. Standard-of-care imaging (e.g., FDG-PET/CT, PSMA-PET/CT, CT or MRI) already available for each participant is used as the reference for intra-individual comparison. The total radiation dose is approximately 7 mSv (≈3.5 mSv PET + ≈3.5 mSv low-dose CT), comparable to standard clinical PET/CT exposure.

Population:

Approximately 770 participants (age ≥18) will be recruited consecutively across 17 indication-specific subgroups: thyroid pathology; head and neck cancer (including cancer of unknown primary); neck node metastases from cancer of unknown primary; sinonasal tract tumor; sarcoidosis; thyroid cancer (suspected recurrence/persistence); breast cancer; hepatocellular carcinoma; gastric cancer; pancreatic cancer; prostate cancer (biochemical recurrence with negative PSMA-PET); urothelial carcinoma; multiple myeloma/plasmocytoma; mesothelioma; hepatic fibrosis; endometriosis; and lung fibrosis. Full eligibility criteria and per-indication enrollment targets are provided in the Eligibility Criteria module.

Investigational Medicinal Product:

[18F]FAPI-74 is a fluorine-18-labelled small-molecule inhibitor targeting FAP. Administered activity is approximately 250 MBq, with a permissible site-specific range of 200-300 MBq. Route of administration is intravenous slow bolus injection (5-15 seconds). The product is manufactured at the USZ Radiopharmacy under GMP conditions, using precursor material supplied by SOFIE Biosciences. Imaging is performed 45-60 minutes post-injection.

Procedures:

Screening includes eligibility assessment, informed consent, collection of demographic and clinical information, and review of historical imaging. Study Visit (Day 0) includes reconfirmation of eligibility, radiotracer injection, a 45-60 minute uptake phase, PET/CT or PET/MR acquisition, adverse event assessment, and discharge. This is a single-visit study; no follow-up visits are planned.

Outcomes:

Primary and secondary outcome definitions, including uptake classification, image quality rating, and comparison methodology against reference imaging, are provided in full in the Outcome Measures module.

Statistical Methods:

The study is descriptive and exploratory in nature. No hypothesis-driven power calculation was performed; sample size was determined based on prior experience with comparable diagnostic imaging studies, published literature, and feasibility considerations.

Quality Assurance:

Monitoring is performed by the Clinical Trials Center (CTC), University Hospital Zurich, in accordance with ICH-GCP and the Swiss Ordinance on Clinical Trials (ClinO). Study data are collected in REDCap® and pseudonymised; imaging data remain stored in institutional PACS systems under standard institutional access controls.

Funding and Insurance:

Each participating centre covers its own operational costs. Precursor material for [18F]FAPI-74 is supplied by SOFIE Biosciences under contractual agreement. Insurance coverage is provided through the Sponsor-Investigator's institutional policy (Baloise Versicherung AG), in accordance with ClinO Annex 2.

02

Conditions studied

  • Thyroid Pathology
  • Head and Neck Cancer (H&N)
  • Sinonasal Tract Tumor
  • Sarcoidosis
  • Thyroid Cancer
  • Breast Cancer
  • Hepatocellular Carcinoma (HCC)
  • Gastric Cancer (GC)
  • Pancreatic Cancer, Adult
  • Urothelial Carcinoma (UC)
  • Multiple Myeloma or Plasmacytoma
  • Mesothelioma
  • Hepatic Fibrosis
  • Endometriosis (Diagnosis)
  • Lung Fibrosis
  • Neck Node Metastasis
  • Prostate Cancer (CRPC)

Keywords

  • [18F]FAPI-74
  • Fibroblast Activation Protein
  • FAP-targeted imaging
  • PET/CT
  • Radiotracer
  • Diagnostic imaging
  • Multicentric study
  • Radiopharmaceutical
  • FAPI
  • FAPI-74
  • nuclear medicine
  • University Hospital Zurich
  • swiss multicenter trial
  • Cancer-associated fibroblast imaging
  • oncologic imaging
  • non-oncologic imaging
03

In context

Thyroid Neoplasms Reclassified

785 studies on the registry are indexed under Thyroid Neoplasms; 204 are open to participants now.

This study's planned enrollment of 770 is above the median of 53 across 520 interventional studies indexed under Thyroid Neoplasms.

Browse Thyroid Neoplasms studies →

Lead sponsor

This is the only study on the registry with Martin Huellner as lead sponsor.

Compared within Thyroid Neoplasms, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Head and Neck Neoplasms. The counts are of registry records indexed under each term, refreshed daily. How we classify →

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Written obtained and documented by the participant's signature.
  • Age ≥18 years at the time of consent.
  • Clinically established or suspected diagnosis or recurrence of an oncologic or non-oncologic disease as defined in chapter 7.1 of study protocol.
  • Availability of standard-of-care imaging (e.g., clinically established PET tracer or anatomical imaging such as CT/MRI) to allow comparative evaluation.

Exclusion criteria

Exclusion Criteria:

  • Severe claustrophobia that would preclude PET imaging.
  • Inability to remain still for the duration of the PET/MR examination.
  • Current pregnancy or breastfeeding; no pregnancy test is required for women who are for ≥12 months or have undergone surgical sterilization, bilateral oophorectomy, or hysterectomy.
  • Previous reactions to radiotracer administration
  • Inability to understand the study information, for example due to language barriers.
  • Subjects incapable of judgment (e.g. individuals under legal or medical incapacity).
  • Participants scheduled for PET/MR imaging: Presence of MRI-incompatible metallic implants, electronic devices (e.g. pacemakers, cochlear implants), or other ferromagnetic foreign bodies.
Terms in these criteria, in plain language(3)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

05

Study design

Phase
Phase 1 / Phase 2
Primary purpose
Diagnostic
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
770 participants (estimated)

Study arms

  • Experimental
    [18F]FAPI-74 PET Imaging

    Participants receive a single intravenous injection of approximately 250 MBq \[18F\]FAPI-74 (fluorine-18 labelled FAP-targeted PET radiotracer), followed by one PET/CT or PET/MR scan performed 45-60 minutes post-injection. For PET/CT acquisitions, a low-dose CT is performed for attenuation correction and anatomical localization. No therapeutic intervention, randomization, or repeat tracer administration is involved. Uptake and diagnostic image quality are assessed qualitatively by a nuclear medicine physician from the local study team. Findings are compared with each participant's own previously acquired standard-of-care imaging (e.g., FDG-PET/CT, PSMA-PET/CT, CT, or MRI), which serves as the reference standard rather than a concurrent study arm. Total participation time is approximately 2 hours on a single study day.

    Drug: [18F]FAPI-74 PET/CT

Interventions

  • Drug[18F]FAPI-74 PET/CT

    Drug page: Fluorine F 18 FAPI-74

    18F\]FAPI-74 is a fluorine-18 labelled, quinoline-based small-molecule inhibitor targeting fibroblast activation protein (FAP), a transmembrane glycoprotein selectively expressed on cancer-associated fibroblasts and in fibrotic/inflammatory tissue. Each participant receives a single intravenous slow-bolus injection (5-15 seconds) of approximately 250 MBq (permissible range 200-300 MBq), followed by a 45-60 minute uptake period and one PET/CT or PET/MR acquisition. The product is manufactured under GMP at the USZ Radiopharmacy using precursor material supplied by SOFIE Biosciences. Unlike clinically established PET tracers (e.g., FDG, PSMA-ligands), \[18F\]FAPI-74 is not yet authorized in Switzerland and is administered exclusively within this investigational protocol for diagnostic evaluation purposes only.

    Also known as: FAPI PET

06

What researchers measure

Primary outcomes

  1. Diagnostic Interpretability and Uptake Classification of [18F]FAPI-74 PET Imaging

    Qualitative assessment of \[18F\]FAPI-74 uptake by a local nuclear medicine physician, classified as FAPI-positive or FAPI-negative in target lesions or disease-specific regions. Overall diagnostic image quality will additionally be rated using a 4-point scale: fully diagnostic, almost fully diagnostic, diagnostically limited, or non-diagnostic. The primary analysis will report the proportion of participants with diagnostically interpretable \[18F\]FAPI-74 images, per indication and pooled across indications.

    Time frame: At the time of [18F]FAPI-74 PET/CT or PET/MR image acquisition and interpretation, performed 45-60 minutes after tracer injection, on the single study visit day.

Secondary outcomes

  1. Lesion-Wise Comparison of [18F]FAPI-74 Uptake with Standard-of-Care Reference Imaging

    Qualitative and semi-quantitative comparison of \[18F\]FAPI-74 uptake with each participant's available standard-of-care reference imaging (e.g., FDG-PET/CT, PSMA-PET/CT, or morphological imaging such as CT/MRI), performed on a lesion-wise basis. Comparative ratings will classify \[18F\]FAPI-74 findings as providing more, comparable, or less diagnostic information relative to the reference imaging. Where available, histopathology or composite clinical/imaging follow-up will serve as the reference standard for calculating sensitivity, specificity, and positive predictive value per indication.

    Time frame: At the time of [18F]FAPI-74 image interpretation, compared against each participant's most recent standard-of-care reference imaging obtained as part of routine clinical care

  2. Change in Diagnostic Confidence and Clinical Management Following [18F]FAPI-74 Imaging

    Change in diagnostic confidence and clinical management recommendations, determined by comparing physician assessments performed before versus after review of \[18F\]FAPI-74 imaging. Diagnostic confidence will be rated on a defined scale; management change will be recorded as a binary indicator (yes/no), with the type of change categorized (e.g., additional biopsy recommended, therapy switch, change in staging). Clinical impact of \[18F\]FAPI-74 findings will additionally be classified as major impact (change in diagnosis or management), minor impact (additional findings not altering management), or no impact.

    Time frame: Diagnostic confidence and management recommendations assessed immediately before and after review of [18F]FAPI-74 imaging, on the single study visit day.

07

Study locations

5 sites
08

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Start is estimated for Aug 2026; primary completion for Sep 2029, 37 months later.

Of 21 phase 1/2 interventional studies under Thyroid Neoplasms, half reached primary completion within 36 months of starting (the median), counting those still running; a quarter within 28 and three quarters within 81. This study's planned 37 months is close to that.

How these figures are worked out, and which studies are left out of them.

Registered
Jul 1, 2026
First posted
Jul 15, 2026
StartEst.
Aug 2026
Primary completionEst.
Sep 2029
CompletionEst.
Sep 2029
Last update
Jul 15, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jul 15, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT07705074
Lead sponsor
Martin Huellner
Collaborators
University Hospital, Zürich
Responsible party
Martin Huellner (Prof. Dr. med., University of Zurich) — Sponsor-investigator
First posted
Jul 15, 2026
Start date
Aug 2026 (estimated)
Primary completion
Sep 2029 (estimated)
Completion
Sep 2029 (estimated)
Last update
Jul 15, 2026

Study contacts

Martin Hüllner, Prof. Dr. med.
Contact
martin.huellner@usz.ch
0041442552580
Patrick Perron, Masters Degree
Contact
patrick.perron@usz.ch
0041442552827
Martin Hüllner, Prof. Dr. med.
principal investigator · Department for Nuclear Medicine, University Hospital Zurich

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.

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Discussion

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Studies of the drug tested here: Fluorine F 18 FAPI-74

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