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RecruitingNCT07664397Updated Oct 1, 2026

Imaging Study of [89Zr]DFO-YS5 for Cancer Detection

A Phase 1 interventional study of [89Zr]DFO-YS5 and Positron Emission Tomography (PET)-Computerized tomography (CT) in Bladder Cancer, Nerve Sheath Tumor and Nerve Sheath Tumors, sponsored by Robert Flavell, MD, PhD. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-01.

Sponsored by Robert Flavell, MD, PhD · Phase 1, Interventional, and Diagnostic

From the registry’s dates

  • Started Jun 2026; still recruiting 3 months later.
Updated Oct 1, 2026Now RecruitingSite recruiting status changed+3 moreGo to Updates ↓
Phase
Phase 1
Study type
Interventional
Enrollment
40
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This is a single-center, pilot, PET-imaging study of the novel radiotracer 89Zirconium-89 DFO conjugated to the YS5 monoclonal antibody ([89Zr]DFO-YS5) in participants with nerve sheath tumor, bladder cancer, or advanced solid tumor neoplasms.

Read the detailed description

PRIMARY OBJECTIVE:

I. To descriptively report patterns of [89Zr]DFO-YS5 uptake on whole-body PET.

SECONDARY OBJECTIVE:

II. To determine the safety of [89Zr]DFO-YS5.

OUTLINE:

Participants will be administered a single dose of [89Zr]DFO-YS5 followed by whole-body positron emission tomography (PET) imaging at a single time point. All participants will be followed for adverse events for approximately Participants in the main study will be followed for adverse events for approximately 1 month after [89Zr]DFO-YS5 radiotracer administration.

02

Conditions studied

  • Bladder Cancer
  • Nerve Sheath Tumor
  • Nerve Sheath Tumors
  • Solid Tumor Malignancies
  • Solid Tumor Cancer
  • Solid Tumor Neoplasms
  • Advanced Solid Tumor
  • Bladder Neoplasm
  • Nerve Sheath Neoplasms
  • Nerve Sheath Tumor, Nos
  • Solid Tumor, Adult
  • Solid Carcinoma

Keywords

  • Imaging Study
03

In context

Urinary Bladder Neoplasms

1,616 studies on the registry are indexed under Urinary Bladder Neoplasms; 421 are open to participants now.

This study's planned enrollment of 40 is below the median of 60 across 1,163 interventional studies indexed under Urinary Bladder Neoplasms.

Browse Urinary Bladder Neoplasms studies →

Lead sponsor

Robert Flavell, MD, PhD is the lead sponsor of 6 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

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

Inclusion criteria

  1. Histological or cytological confirmation of malignant peripheral nerve sheath tumor, bladder cancer, or solid tumor neoplasm.
  2. At least one soft tissue lesion measurable at 1 cm or greater in short axis measurement on cross sectional imaging such as Computerized tomography (CT), magnetic resonance imaging (MRI), or Positron Emission Tomography (PET)/CT (scan imaging as documented in the medical record). Exception: For participants with localized bladder cancer (pre-cystectomy), lesions smaller than 1 centimeter (cm) are permitted, provided there is cystoscopic confirmation of a bladder mass.
  3. Clinically able to undergo PET-CT imaging.
  4. Age ≥ 18 years.
  5. Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 2 or Karnofsky ≥ 50% (see Appendix 1).
  6. Adequate organ function as defined below:

    • Total bilirubin: ≤ 1.5 x institutional upper limit of normal (ULN) (unless elevated due to Gilbert's syndrome and direct bilirubin is within normal limits).
    • Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase (SGOT)): ≤ 3 x ULN.
    • Alanine aminotransferase (ALT) (serum glutamic-pyruvic transaminase (SGPT)): ≤ 3 x ULN.
    • Estimated creatinine clearance: ≥ 30 mL/min, calculated using the Cockcroft-Gault equation.
  7. Females of reproductive potential (defined below) must be willing to undergo a urine or serum pregnancy test (i.e., human chorionic gonadotropin test) within 72 hours before administration of [89Zr]DFO-YS5. A female is considered to NOT be of reproductive potential (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice), if they meet either of the following two criteria: (1) has reached a postmenopausal state (≥ 12 continuous months of amenorrhea with no identified cause other than menopause); or (2) has undergone surgical sterilization (i.e., hysterectomy and/or bilateral oophorectomy for removal of uterus and/or ovaries). The result of the urine or serum pregnancy test must be negative in order to initiate the [89Zr]DFO-YS5 administration. If a urine pregnancy test is positive or equivocal, a confirmatory a serum pregnancy test is required. The individual must be excluded from participation if the serum pregnancy result is positive. Pregnant individuals are excluded from this study because there is an unknown but potential risk for adverse effects in the unborn child secondary to treatment of the study participant with [89Zr]DFO-YS5.
  8. Individuals with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or endpoints of this study are eligible.
  9. Ability to understand and the willingness to sign a written informed consent document.

Exclusion criteria

Exclusion Criteria:

  1. Individuals with a contraindication to PET-CT imaging (e.g., severe claustrophobia) (e.g., implanted devices, metallic objects, or other implants). Participants must be able to undergo either PET-CT.
  2. Individuals who are pregnant or breastfeeding/chest-feeding.

    • Breastfeeding/chestfeeding should be discontinued before administration of [89Zr]DFO-YS5.
    • Females of childbearing potential (defined below) must have a negative urine or serum pregnancy test (i.e., human chorionic gonadotropin test) within 72 hours prior to administration of [89Zr]DFO-YS5. If the urine pregnancy test is positive or equivocal, a confirmatory serum pregnancy test is required. In such cases, the individual must be excluded from participation if the serum pregnancy result is positive.

    A female is considered to be of childbearing potential (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice), unless it is documented that the individual meets either of the following two criteria: (1) has reached a postmenopausal state (≥ 12 continuous months of amenorrhea with no identified cause other than menopause); or (2) has undergone surgical sterilization (i.e., hysterectomy and/or bilateral oophorectomy for removal of uterus and/or ovaries).

    Individuals who are pregnant or breastfeeding/chestfeeding are excluded because there is an unknown but potential risk for adverse effects in the unborn/nursing child secondary to treatment of the study participant with [89ZR]-DFO-YS5.

  3. Hypersensitivity to [89Zr]DFO-YS5 or any of its excipients.
  4. Individuals with any condition or social circumstance that, in the opinion of the investigator, would impair the participant's ability to comply with study procedures.
05

Study design

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

Study arms

  • Experimental
    Treatment ([89Zr]DFO-YS5)

    Participants will be administered a single, intravenous microdose (1.0 - 3.0 mCi) of \[89Zr\]DFO-YS5, followed by whole-body positron emission tomography (PET) imaging conducted 120-168 hours after \[89Zr\]DFO-YS5 administration (i.e., on Day 6-8). Participants will be followed for treatment-emergent adverse events for up to 35 days.

    Drug: [89Zr]DFO-YS5 · Procedure: Positron Emission Tomography (PET)-Computerized tomography (CT)

Interventions

  • Drug[89Zr]DFO-YS5

    Given intravenously (IV)

    Also known as: 89Zirconium-89 DFO conjugated to the YS5 monoclonal antibody

  • ProcedurePositron Emission Tomography (PET)-Computerized tomography (CT)

    Participants may receive a whole-body PET-CT or a whole-body PET-MRI

    Also known as: PET/CT, PET-CT

06

What researchers measure

Primary outcomes

  1. Mean maximum standard uptake value (SUVmax-avg) on Positron Emission Tomography (PET) scan

    A volume of interest (VOI) will be placed around each lesion, and the calculated maximum standard uptake value (SUVmax) will be recorded for each lesion. Adjusted SUVmax data will then be averaged across up to 15 lesions within a given patient (SUVmax-avg) at each time point. In order to avoid clustering effects, analyses will be limited to the five largest osseous metastases, five largest lymph node metastases, and five largest visceral/soft tissue metastases. Metastatic lesion location, size (bidimensional axial measurement), and SUVmax will be tabulated. This will be conducted for all lesions.

    Time frame: Up to 8 days

  2. Median intra-tumoral SUVmax

    The median and range for intra-tumoral SUVmax within metastatic lesions will be descriptively reported, to assess for intra-tumoral heterogeneity and differences in uptake by site of disease.

    Time frame: Up to 8 days

  3. Tumor-to-background signal (Ratio)

    The tumor-to-background signal refers to comparing the standardized uptake value (SUV) of a lesion (tumor) to the SUV of a nearby normal organ or tissue that serves as a "background" reference. The ratio of the tumor-to-background signal on PET scan (normal organ as background uptake values) will be calculated as the SUVmax of tumor divided by the SUV of background organ

    Time frame: Up to 8 days

Secondary outcomes

  1. Proportion of participants with reported treatment-emergent adverse events

    The proportion of participants with reported treatment-emergent Adverse events (AEs) will be classified and graded according to the NCI CTCAE version. 5.0 by severity and type evaluated from the time of administration through the Day 6-8 Visit (120-168 hours post-dose).

    Time frame: Up to 8 days

07

Study locations

1 of 1 sites recruiting
  • University of California, San Francisco
    San Francisco, California 94143, United States
    Recruiting
08

References and documents

Individual participant data

Plan to share: Yes — De-identified data may be shared with study collaborators during the course of data collection.

Supporting information: Study protocol, Sap

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Status
Not yet recruiting→Recruiting
changed Oct 1, 2026
Sites
University of California, San Francisco is now Recruiting
Oct 1, 2026
Start date
Aug 1, 2026→Jun 15, 2026 (actual)
Oct 1, 2026
Also revised
eligibility and interventions
Show all 1 update
  1. Oct 1, 2026
    Not yet recruiting→Recruiting
    University of California, San Francisco is now Recruiting
    Start date Aug 1, 2026→Jun 15, 2026 (now actual)
    Eligibility Criteria revised
    Interventions Arms or interventions changed
    + 1 other change: verification date

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07664397
Lead sponsor
Robert Flavell, MD, PhD
Collaborators
Kyntra Bio, Fortis Therapeutics, Inc.
Responsible party
Robert Flavell, MD, PhD (Principal Investigator, University of California, San Francisco) — Sponsor-investigator
First posted
Jun 24, 2026
Start date
Jun 15, 2026
Primary completion
Sep 30, 2029 (estimated)
Completion
Sep 30, 2029 (estimated)
Last update
Oct 1, 2026

Study contacts

Maya Aslam
Contact
Maya.Aslam@ucsf.edu
877-827-3222
Robert Flavell, MD
principal investigator · University of California, San Francisco

Oversight

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

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