Recruiting
Phase 1

\[89Zr\]DFO-YS5

Sponsor:

Robert Flavell, MD, PhD

Code:

NCT07664397

Conditions

Bladder Cancer

Nerve Sheath Tumor

Nerve Sheath Tumors

Solid Tumor Malignancies

Solid Tumor Cancer

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

[89Zr]DFO-YS5

Positron Emission Tomography (PET)-Computerized tomography (CT)

Study Details

Brief 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.

Conditions

Bladder Cancer

Nerve Sheath Tumor

Nerve Sheath Tumors

Solid Tumor Malignancies

Solid Tumor Cancer

Study ID

NCT07664397

Start date

Jun 15, 2026

Status verified date

Sep, 2026

Completion date

Sep 30, 2029

Anticipated

Primary completion date

Sep 30, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

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:

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.

Study Design

Enrollment

40 participants

Anticipated

Intervention Model

Single group

Primary purpose

Diagnostic

Interventions and Outcome Measures

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.

Interventions

[89Zr]DFO-YS5

Given intravenously (IV)

Positron Emission Tomography (PET)-Computerized tomography (CT)

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

Primary outcome measure

  • Mean maximum standard uptake value (SUVmax-avg) on Positron Emission Tomography (PET) scan [ Time Frame: Up to 8 days ]
  • Median intra-tumoral SUVmax [ Time Frame: Up to 8 days ]
  • Tumor-to-background signal (Ratio) [ Time Frame: Up to 8 days ]

Central Contacts and Locations

Central contacts

Locations

University of California, San Francisco

Recruiting

San Francisco, California, United States, 94143

Contacts

Principal Investigator:

Robert Flavell, MD

More Information

Sponsor

Robert Flavell, MD, PhD

Last update posted

Oct 1, 2026

Last verified

Sep, 2026

Keywords

  • Imaging Study

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-02. This information was provided to ClinicalTrials.gov by Robert Flavell, MD, PhD on 2026-10-01. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.