CompletedNCT04743310Updated Jul 10, 2026Results posted

Fluorescence Detection of Adult Primary Central Nervous System Tumors With Tozuleristide and the Canvas System

A Phase 2 interventional study of tozuleristide and Canvas imaging system in Central Nervous System Tumor, sponsored by John Yu. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-10.

Sponsored by John Yu · Phase 2, Interventional, and Treatment

Phase: Phase 2
Study type: Interventional
Enrollment: 50
Allocation: Not applicable
Ages: 18 Years and older
Sex: All

Study summary

The purpose of this study is to examine the use of a single dose of tozuleristide (24 or 36 mg) and the Canvas imaging system during surgical resection of primary central nervous system (CNS) tumors: Primary gadolinium enhancing (high grade) CNS tumors, primary non-gadolinium enhancing CNS tumors, and primary vestibular schwannoma.

The primary objectives of the study is to see how well tozuleristide and the Canvas imaging system during surgical resection will show fluorescence among primary enhancing/high grade CNS tumors; and among the tumors that demonstrate tozuleristide fluorescence, to estimate the true positive rate and true negative rate of fluorescence in tissue biopsies, as well as sensitivity and specificity of tozuleristide fluorescence for distinguishing tumor from non-tumoral tissue.

The secondary objectives of the study include evaluating the safety of tozuleristide and the Canvas imaging system, and to determine if the presence of remaining fluorescence at the time of surgery corresponds to remaining tumor evident on post-operative MRI images, or if the absence of fluorescence corresponds to evidence of no gross residual tumor on post-operative magnetic resonance imaging (MRI).

Conditions studied

Central Nervous System Tumor

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Keywords

neurosurgery
brain tumor
spinal cord tumor
surgical resection
glioma
astrocytoma
glioblastoma
ependymoma
medulloblastoma
pineocytoma
meningioma
germ cell tumor
craniopharyngioma
oligoastrocytoma
pineoblastoma
extent of resection
maximal safe resection
neuropathology
vestibular schwannomas

In context

Central Nervous System Neoplasms

699 studies on the registry are indexed under Central Nervous System Neoplasms; 66 are open to participants now.

This study's enrollment of 50 is above the median of 35 across 487 interventional studies indexed under Central Nervous System Neoplasms.

Browse Central Nervous System Neoplasms studies →

Lead sponsor

This is the only study on the registry with John Yu as lead sponsor.

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

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

MRI obtained within 30 days of study enrollment documents a consistent with a primary malignant central nervous system tumor for which maximal safe resection is indicated OR MRI obtained within 30 days of study enrollment documents a measurable lesion consistent with a primary schwannoma enhancing tumor in the cerebellopontine angle for which maximal safe resection is indicated.
Adequate renal and liver function
Subjects with prior therapy are eligible provided they have recovered from any acute toxic effects of prior therapy and have sufficient time interval prior to enrollment.

Exclusion criteria

Exclusion Criteria:

Pregnant, breast-feeding, or planning to conceive a child within 30 days
Ongoing serious medical conditions such that participation in the study could put the subject at increased risk of worsening their condition
Subjects planned to undergo only a diagnostic procedure, without intent to resect tissue for therapeutic purposes
Subjects for whom radiographic evidence suggests a non-intra-axial primary brain tumor

Terms in these criteria, in plain language(2)

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.

Measurable disease

The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.

The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.

Biopsy and archival tissue

A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.

Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Enrollment: 50 participants (actual)

Study arms

Experimental
Tozuleristide with Canvas imaging system
Drug: tozuleristide · Device: Canvas imaging system · Procedure: Surgical resection of tumor

Interventions

Drugtozuleristide
tozuleristide 24 or 36 mg administered intravenously 1-24 hours prior to surgery
DeviceCanvas imaging system
imaging device attached to surgical microscope
ProcedureSurgical resection of tumor
Standard of care surgical resection of tumor

What researchers measure

Primary outcomes

Percentage of Patients With Fluorescence-positive Primary Tumor Biopsy
Time frame: At the time of surgery
True Positive Rate of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Tumor-positive Tissue Biopsies
Time frame: At the time of surgery
True Negative Rate of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Tumor-negative Tissue Biopsies
Time frame: At the time of surgery

Secondary outcomes

Positive Predictive Value of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Fluorescence-positive Tissue Biopsies
Time frame: At the time of surgery
Negative Predictive Value of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Fluorescence-negative Tissue Biopsies
Time frame: At the time of surgery
Extent of Residual Tumor Measured on Post-operative Magnetic Resonance Imaging Scans Among All Patients With Evidence of Residual Fluorescence at the Time of Surgery
To preliminarily determine if the presence of residual fluorescence at the time of surgery corresponds to residual tumor evident on post-operative MRI images, or if the absence of fluorescence corresponds to evidence of no gross residual tumor on post-operative MRI. This measure reports the number of participants that met the criteria for each extent of resection category based on post-operate MRI findings. In order from best to worst in terms of extent of resection: Gross total resection means no residual gadolinium enhancing tumor on postoperative MRI, Near gross total resection means minimal residual gadolinium enhancing tumor on MRI, less than 0.5 cm cubed, Subtotal resection means residual gadolinium enhancing tumor noted on post operative MRI, and Biopsy only means residual tumor from a biopsy only of the tumor.
Time frame: At the time of surgery

Other outcomes

Incidence of Adverse Events
Recorded and graded according to the National Cancer Institute's Common Terminology Criteria for Adverse Events Version 5
Time frame: From the time of study drug administration 1-24 hours prior to surgery, until 30 days after surgery or until receiving additional therapy for the central nervous system tumor, whichever comes first

Results

Posted Jul 10, 2026

Participant flow

The trial opened to accrual on 9/27/2021 with first subject enrolled on study 9/30/2021. A total of 56 patients consented; 6 subjects failed screening; 50 subjects were enrolled/went on study/on treatment, 46 completed study intervention, and 45 were deemed evaluable. The last subject went off treatment on 3/5/2025. Last data collection for primary endpoint confirmed on 3/6/2025 as the primary completion date. 0 subjects are in follow-up.

Participant flow — Overall Study
Milestone	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Started	38	8	4
Completed	34	8	4
Not completed	4	0	0
Withdrew: Withdrawal by subject	1	0	0
Withdrew: Canvas device deficiency	1	0	0
Withdrew: Physician decision	2	0	0

Outcome measures

PrimaryPercentage of Patients With Fluorescence-positive Primary Tumor Biopsy

Time frame:: At the time of surgery
Reported as:: Number · percentage of participants

Percentage of Patients With Fluorescence-positive Primary Tumor Biopsy
percentage of participants	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Percentage of Patients With Fluorescence-positive Primary Tumor Biopsy	82.35	14.29	100

PrimaryTrue Positive Rate of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Tumor-positive Tissue Biopsies

Time frame:: At the time of surgery
Reported as:: Number · % tumor+ & fluor + / Tumor+ biopsies

True Positive Rate of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Tumor-positive Tissue Biopsies
% tumor+ & fluor + / Tumor+ biopsies	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
True Positive Rate of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Tumor-positive Tissue Biopsies	83.97	20	100

PrimaryTrue Negative Rate of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Tumor-negative Tissue Biopsies

Time frame:: At the time of surgery
Reported as:: Number · % tumor- & fluor - /Tumor- biopsies

True Negative Rate of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Tumor-negative Tissue Biopsies
% tumor- & fluor - /Tumor- biopsies	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
True Negative Rate of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Tumor-negative Tissue Biopsies	21.43	—	0

SecondaryPositive Predictive Value of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Fluorescence-positive Tissue Biopsies

Time frame:: At the time of surgery
Reported as:: Number · % tumor+ & fluor + /Flour+ biopsies

Positive Predictive Value of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Fluorescence-positive Tissue Biopsies
% tumor+ & fluor + /Flour+ biopsies	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Positive Predictive Value of Fluorescence, Defined as the Percentage of Tumor-positive and Fluorescence-positive Tissue Biopsies Among All Fluorescence-positive Tissue Biopsies	83.46	100	95

SecondaryNegative Predictive Value of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Fluorescence-negative Tissue Biopsies

Time frame:: At the time of surgery
Reported as:: Number · % tumor-& fluor -/Flour- biopsies

Negative Predictive Value of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Fluorescence-negative Tissue Biopsies
% tumor-& fluor -/Flour- biopsies	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Negative Predictive Value of Fluorescence, Defined as the Percentage of Tumor-negative and Fluorescence-negative Tissue Biopsies Among All Fluorescence-negative Tissue Biopsies	22.22	—	—

SecondaryExtent of Residual Tumor Measured on Post-operative Magnetic Resonance Imaging Scans Among All Patients With Evidence of Residual Fluorescence at the Time of Surgery

To preliminarily determine if the presence of residual fluorescence at the time of surgery corresponds to residual tumor evident on post-operative MRI images, or if the absence of fluorescence corresponds to evidence of no gross residual tumor on post-operative MRI. This measure reports the number of participants that met the criteria for each extent of resection category based on post-operate MRI findings. In order from best to worst in terms of extent of resection: Gross total resection means no residual gadolinium enhancing tumor on postoperative MRI, Near gross total resection means minimal residual gadolinium enhancing tumor on MRI, less than 0.5 cm cubed, Subtotal resection means residual gadolinium enhancing tumor noted on post operative MRI, and Biopsy only means residual tumor from a biopsy only of the tumor.

Time frame:: At the time of surgery
Reported as:: Number · Participants

Extent of Residual Tumor Measured on Post-operative Magnetic Resonance Imaging Scans Among All Patients With Evidence of Residual Fluorescence at the Time of Surgery
Participants	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Gross total resection (GTR)	2	—	1
Near total resection	7	—	1
Subtotal resection	4	—	1
Biopsy Only	0	—	0

Other pre-specifiedIncidence of Adverse Events

Recorded and graded according to the National Cancer Institute's Common Terminology Criteria for Adverse Events Version 5

Time frame:: From the time of study drug administration 1-24 hours prior to surgery, until 30 days after surgery or until receiving additional therapy for the central nervous system tumor, whichever comes first
Reported as:: Number · adverse events

Incidence of Adverse Events
adverse events	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Incidence of Adverse Events	152	24	23

Adverse events

Collected over The investigator or designee is responsible for ensuring that all adverse events (both serious and non-serious) observed by the clinical team or reported by the subject, which occur from start of first dose of study drug and until 30 days following surgery or until subject begins another cancer therapy (whichever occurs first), are fully recorded in the subject's medical records. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Cohort 1: Enhancing (High Grade) CNS Tumors	0/38 (0%)	5/38 (13.2%)	31/38 (81.6%)
Cohort 2: Non-enhancing CNS Tumors	0/8 (0%)	2/8 (25%)	6/8 (75%)
Cohort 3: Vestibular Schwannomas	0/4 (0%)	1/4 (25%)	4/4 (100%)

Most frequent serious events

Showing 10 of 13

Most frequent serious events
Event	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
Wound InfectionInfections and infestations	0/38	0/8	1/4
FeverGeneral disorders	0/38	1/8	0/4
Periorbital EdemaInfections and infestations	0/38	1/8	0/4
MyalgiaMusculoskeletal and connective tissue disorders	0/38	1/8	0/4
DysphasiaNervous system disorders	2/38	0/8	0/4
DysphagiaGastrointestinal disorders	1/38	0/8	0/4
FatigueGeneral disorders	1/38	0/8	0/4
Generalized Muscle WeaknessMusculoskeletal and connective tissue disorders	1/38	0/8	0/4
EncephalopathyNervous system disorders	1/38	0/8	0/4
HydrocephalusNervous system disorders	1/38	0/8	0/4

Most frequent other events

Showing 10 of 52

Most frequent other events
Event	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas
HeadacheNervous system disorders	11/38	3/8	2/4
Hearing ImpairedEar and labyrinth disorders	0/38	0/8	2/4
DizzinessNervous system disorders	3/38	0/8	2/4
ConstipationGastrointestinal disorders	5/38	3/8	1/4
FatigueGeneral disorders	5/38	3/8	1/4
NauseaGastrointestinal disorders	3/38	2/8	1/4
HypertensionBlood and lymphatic system disorders	0/38	0/8	1/4
Eyelid Function DisorderEye disorders	0/38	0/8	1/4
VomitingGastrointestinal disorders	0/38	0/8	1/4
Facial PainGeneral disorders	0/38	0/8	1/4

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
<=18 years	0	0	0	0
Between 18 and 65 years	26	7	1	34
>=65 years	12	1	3	16

Age, Continuous
Age, Continuous(years)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
Median	60 (23 to 82)	47 (26 to 76)	67 (37 to 68)	59.5 (23 to 82)

Sex: Female, Male
Sex: Female, Male(Participants)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
Female	17	0	0	17
Male	21	8	4	33

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
Hispanic or Latino	8	0	0	8
Not Hispanic or Latino	30	8	4	42
Unknown or Not Reported	0	0	0	0

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
American Indian or Alaska Native	0	0	0	0
Asian	3	2	1	6
Native Hawaiian or Other Pacific Islander	0	0	0	0
Black or African American	3	1	0	4
White	26	5	3	34
More than one race	5	0	0	5
Unknown or Not Reported	1	0	0	1

Region of Enrollment
Region of Enrollment(participants)	Cohort 1: Enhancing (High Grade) CNS Tumors	Cohort 2: Non-enhancing CNS Tumors	Cohort 3: Vestibular Schwannomas	Total
United States	38	8	4	50

Study locations

1 site

Cedars-Sinai Medical Center
Los Angeles, California 90048, United States

References and documents

Study documents

Protocol and statistical analysis plan ↗ · Sep 4, 2024
Informed consent form ↗ · Mar 4, 2025

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

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

Ran from Sep 2021 to primary completion in Mar 2025, 41 months.

Results were first posted in Jul 2026, 1 year 4 months after primary completion.

Of 50 non-industry phase 2 interventional studies under Central Nervous System Neoplasms, half reached primary completion within 56 months of starting (the median), counting those still running; a quarter within 44 and three quarters within 77. This study's 41 months is below that.

Counting every sponsor, half of 54 studies reached it within 58 months; a quarter within 44 and three quarters within 77.

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

Registered: Feb 4, 2021
First posted: Feb 8, 2021
StartActual: Sep 30, 2021
Primary completionActual: Mar 6, 2025
CompletionActual: Mar 6, 2025
Results first posted: Jul 10, 2026
Last update: Jul 10, 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 10, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04743310
Lead sponsor: John Yu
Collaborators: Blaze Bioscience Inc.
Responsible party: John Yu (Director, Surgical Neuro-Oncology, Cedars-Sinai Medical Center) — Sponsor-investigator
First posted: Feb 8, 2021
Start date: Sep 30, 2021
Primary completion: Mar 6, 2025
Completion: Mar 6, 2025
Results posted: Jul 10, 2026
Last update: Jul 10, 2026

Study contacts

John Yu, MD

principal investigator · Cedars-Sinai Medical Center

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: Yes

View the source record on ClinicalTrials.gov ↗

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