An Early Phase 1 interventional study of 89Zr-DFO-N-Suc-F8scFv and 89Zr-DFO-N-Suc-C9scFv in Solid Tumor, Colon Carcinoma and Rectal Carcinoma, sponsored by Var2 Pharmaceuticals. Recruiting at 1 site in Netherlands. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-29.
Sponsored by Var2 Pharmaceuticals · Early Phase 1, Interventional, and Other
VARTUTRACE is a first-in-human PET/CT molecular imaging study in patients with solid tumors. This study will investigate the biodistribution and pharmacology of two antibody fragments binding oncofetal Chondroitin Sulfate (CS).
Oncofetal CS are tumor-specific carbohydrate motifs present in proteoglycans and identified by VAR2 Pharmaceuticals as expressed during fetal development. Oncofetal CS reappears in the vast majority of cancers while remaining largely absent from normal tissues.
VAR2 Pharmaceuticals recently developed antibodies specific for oncofetal CS. VARTUTRACE uses two of these as radiolabeled antibody fragments to study biodistribution, tumor accumulation, pharmacodynamics and clearance pathways in a diverse patient population.
VARTUTRACE aims to investigate the biodistribution and pharmacology in patients with solid tumors of two antibody fragments specific for oncofetal CS.
VAR2 Pharmaceuticals has identified and characterized oncofetal CS as a group of tumor-specific carbohydrate motifs that appear in placental tissue during fetal development and in most cancers while remaining largely absent from healthy tissue. VAR2 Pharmaceuticals recently developed a panel of antibodies specific for oncofetal CS and characterized their tumor specificity, therapeutic, and safety in pre-clinical models under various formats.
VARTUTRACE is a Phase 0 microdosing study of a single administration of \<30 nmol of one of the two most promising antibody fragments identified by VAR2 Pharmaceuticals - C9 and F8. Both antibody fragments will be used as short chain variable fragments (scFvs) labelled with the radioisotope Zirconium-89 (89Zr) and are therefore respectively named 89Zr-C9scFv or 89Zr-F8scFv. As it remains unclear from the pre-clinical in vitro and in vivo data which of the two will have the most optimal tumor targeting properties in patients with solid tumors, both scFvs will be evaluated.
The biodistribution, pharmacokinetics, pharmacodynamics, and clearance of two of these antibody fragments is planned to be studied in up to 32 patients with various cancers (i.e. a basket-trial).
2,457 studies on the registry are indexed under Colonic Neoplasms; 458 are open to participants now.
This study's planned enrollment of 32 is below the median of 75 across 1,711 interventional studies indexed under Colonic Neoplasms.
Browse Colonic Neoplasms studies →This is the only study on the registry with Var2 Pharmaceuticals as lead sponsor.
Counted across the registry records on this site, refreshed daily.
General Inclusion Criteria:
Adequate liver- and kidney function, defined by the following laboratory results obtained during screening visit:
Medical inclusion Criteria:
Colon Carcinoma:
Rectal Carcinoma:
Bone- and soft-tissue sarcoma
Breast carcinoma
Lung Carcinoma:
Head and Neck Squamous Cell carcinoma (HNSCC):
Oesophageal and gastric carcinoma:
Pancreas carcinoma:
Bladder carcinoma:
Glioblastoma:
General Exclusion Criteria:
Medical Exclusion Criteria:
Current evidence or history of bacterial, viral or fungal infections within 7 days before 89Zr-DFON-Suc-scFv (F8 or C9) administration as judged by the Investigator.
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.
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.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
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).
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
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.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The first 3 patients of this arm will receive a single i.v. microdose (1 mg) administration of 89Zr-F8scFv 15 MBq, followed by three whole-body PET/CT scans on day 1, 2 and 4. After the first three patients, an interim analysis will be conducted to determine the optimal scanning time point and radiation dose. The following 13 patients will receive a single i.v. microdose administration of 89Zr-F8scFv between 15 - 30 MBq, followed by one whole-body PET/CT scan on the optimal scanning day (day 1-7). Each subject will have a follow-up visit approximately 28 days after IMP administration.
Biological: 89Zr-DFO-N-Suc-F8scFv · Radiation: PET/CT scan
The first 3 patients of this arm will receive a single i.v. microdose (1 mg) administration of 89Zr-C9scFv 15 MBq, followed by three whole-body PET/CT scans on day 1, 2 and 4. After the first three patients, an interim analysis will be conducted to determine the optimal scanning time point and radiation dose. The following 13 patients will receive a single i.v. microdose administration of 89Zr-C9scFv between 15 - 30 MBq, followed by one whole-body PET/CT scan on the optimal scanning day (day 1-7). Each subject will have a follow-up visit approximately 28 days after IMP administration.
Biological: 89Zr-DFO-N-Suc-C9scFv · Radiation: PET/CT scan
89-Zirconium labeled short-chain variable fragment F8 targeting oncofetal CS.
89-Zirconium labeled short-chain variable fragment C9 targeting oncofetal CS.
IMP administration will be followed by PET/CT scans on day 1, 2 and 4.
Biodistribution and pharmacokinetics of the radiolabeled IMP
Biodistribution and pharmacokinetics of the IMP are defined by the amount of IMP that is taken up per target organ or tissue over time. The radioactive dose absorbed per target organ or tissue over time is determined using whole-body PET/CT imaging at various time points post-injection. In addition, blood samples will be taken at various time points post-injection to determine IMP plasma level concentrations. The ICRP 89 values will be used to calculate the effective dose in each organ. Descriptive statistics of absorbed doses to target organs and tissues specified will be tabulated. The blood concentrations will be presented using descriptive summary statistics.
Time frame: Day 1, 2, and 4 after dosing
Tumor-specific uptake of the IMP
Tumor-specific uptake of the IMP is defined as the amount of IMP that tumors uptake compared to normal tissue. Tumor-specific uptake of the IMP is captured using PET/CT imaging and quantified by calculating the tumor-to-background ratio (TBR), which is determined by the ratio of radioactivity taken up by the tumor and radioactivity taken up by healthy reference tissue. A qualified PET investigator will obtain the raw data. PET/CT-derived TBR will be quantified for each patient and compared to standard of care imaging techniques. Variables will be presented as qualitative data. Data interpretation is considered descriptive.
Time frame: Day 1 - 7 after dosing
Incidence of treatment emergent adverse events (AE) (safety and tolerability)
Safety and tolerability will be assessed by the number of participants with treatment-emergent AEs, with abnormal laboratory tests results (including the occurrence of anti-drug antibodies), abnormal vital signs, abnormal ECG readings, and abnormal physical examination findings from the time of i.v. administration of the IMP until the end of the follow-up period. For this objective, variables will be presented as qualitative data. Interpretations of this data will be descriptive
Time frame: Study duration (up to 56 days)
Tumor-specific uptake of the IMP per cancer type
Tumor-specific uptake of the IMP will be quantified, as described in outcome measure 2, for each cancer type and compared across cancer types included in this study. Variables will be presented as qualitative data. Data interpretation is considered descriptive.
Time frame: Day 1 -7 after dosing
Presence of IMP and target in patient-derived tumor tissue
The presence of the IMP and the oncofetal CS target in tumor tissue will be determined ex vivo and compared to the tracer signal measured in the tumor tissue in vivo. Presence of the IMP and the oncofetal CS target in patient-derived tissue slices will be determined using immunohistochemical stainings. Tumor-specific uptake of the IMP in vivo will be quantified using PET/CT imaging as described in outcome measure 2. For this objective, variables will be presented as qualitative data. Interpretations of this data will be descriptive.
Time frame: Day 1 - 7 after dosing
Plan to share: No
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