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Study of Safety and Functional Imaging of cG250 and Sunitinib in Patients With Advanced Renal Cell Carcinoma

A Pilot Study of the Safety, Efficacy, and Effects on Functional Imaging of the Combination of cG250 and Sunitinib in Patients With Advanced Renal Cell Carcinoma

Status
Terminated
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00520533
Enrollment
8
Registered
2007-08-24
Start date
2008-02-29
Completion date
2012-09-30
Last updated
2022-10-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Renal Cell Carcinoma (RCC)

Keywords

Clinical trials, cG250 mAb, monoclonal antibody (mAb) G250, sunitinib, angiogenesis inhibitors, Positron-Emission Tomography, Pharmacokinetics, Pharmacodynamics

Brief summary

This clinical trial explores the safety, efficacy, and effects on functional imaging of cG250 monoclonal antibody (mAb) administered intravenously weekly in combination with daily oral sunitinib, in patients with advanced renal cell carcinoma.

Detailed description

This study explores the safety, efficacy and effects on functional imaging of the combination of cG250 and sunitinib in patients with advanced renal cell carcinoma (kidney cancer). When kidney cancer has spread beyond the kidney, it is usually not possible to cure it with surgery. Other treatments such as radiotherapy or chemotherapy are also of limited value. Kidney cancers often rely on certain proteins for their growth, particularly proteins that affect the ways that blood vessels grow into the cancer. Ingrowth of blood vessels supplies cancer cells with oxygen and nutrition; without the blood vessels, cancer deposits can not grow in size. When growth of the blood vessels is blocked, established cancers may stop growing or may shrink. This has been shown to work for some drugs that target this process in kidney cancers. One of these drugs is called sunitinib. A protein, called G250, is also thought to be important in helping kidney cancers to grow. G250 is found on the cell surface of many kidney cancers. One possible method of interfering with the function of G250 is to target G250 with an antibody known as cG250. Clinical trials with cG250 have shown it to be safe, to home in on kidney cancer cells, and to persist in the blood and the cancer tissue for a long period of time. The main purpose of this study is to explore whether the combination of sunitinib and cG250 is safe in patients with advanced kidney cancer. The study will also assess whether this combination is able to cause kidney cancer to shrink; will determine where cG250 travels within the body, whether the immune system reacts to the cG250 and whether sunitinib affects that; and whether the combination affects how kidney cancers grow or how blood flows within the tumour. Eligible patients will receive cG250 10 mg/m² by weekly intravenous infusion for five weeks, followed by a two-week break (one cycle). The first and fifth dose will be trace-labeled with a radioactive substance (124I-cG250) detectable by a special scan called a Positron Emission Tomography (PET scan) to allow studies of the distribution of cG250. Sunitinib 50 mg by daily oral dose will also be given for 4 weeks (commencing on day 8 of the first treatment cycle), followed by a two-week break. Up to two cycles of treatment will be given. If a second cycle is given, cG250 will be given as four weekly doses and daily sunitinib will start on the same day. No 124I-cG250 will be administered after the first treatment cycle. The extent of the kidney cancer will be assessed by Computed tomography (CT) at baseline and at the end of each treatment cycle. Safety assessments (physical examination, blood tests, gated cardiac blood pool scan, ECG-heart trace) will be performed at the beginning of each treatment cycle, repeated throughout the cycle and end of study. A number of blood tests and PET scans will be done in the first cycle to show how and in what amounts the 124I-cG250 distributes in the body. Other PET scans (18F-2-fluoro-2-deoxy-D-glucose fluorodeoxyglucose {\[18\]F-FDG}) and 15O-water {\[15\]O-H2O}) will be performed to allow assessment of tumour growth and blood flow. Blood tests will also show whether the immune system recognises the infused cG250 by making an antibody against it. A total of 14 patients were expected to be recruited; 8 were consented and 6 received study treatment.

Interventions

BIOLOGICALChimeric monoclonal antibody cG250

First Cycle: cG250 10 mg/m² intravenous infusion, weekly for five weeks, followed by a two-week break. 1st & 5th dose will be trace-labeled with a radioactive substance detectable on a PET scanner (124I-cG250). Second cycle (investigator discretion): cG250 10 mg/m² intravenous infusion, weekly for four weeks followed by a two-week break. No 124I-cG250 will be used in the 2nd cycle. Up to 2 cycles available.

DRUGSunitinib malate

First Cycle: Sunitinib 50 mg orally daily for 4 weeks (starts 8th day of 1st treatment cycle), followed by a two-week period off sunitinib. Second cycle (investigator discretion): Sunitinib 50 mg orally daily for 4 weeks (starts on 1st day of 2nd treatment cycle), followed by a two-week period off sunitinib. Up to 2 cycles available on-study.

Sponsors

Pfizer
CollaboratorINDUSTRY
Heidelberg Pharma AG
CollaboratorINDUSTRY
Ludwig Institute for Cancer Research
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Metastatic or unresectable Renal Cell Cancer (with clear cell component). * Measurable disease by RECIST on CT with at least one measurable lesion 2 cm or greater in diameter, which is deemed to be assessable by PET imaging. * At least 4 weeks after chemotherapy, radiotherapy or immunotherapy (6 weeks for nitrosourea drugs). * Expected survival at least 3 months. * Karnofsky performance status (KPS) of 70% or greater. * Age 18 years or older. * Vital laboratory parameters within normal, or protocol specified ranges. * Left ventricular ejection fraction greater than 55% on GCBP scan. * Systolic blood pressure ≤150mmHg and diastolic blood pressure ≤90mmHg. * Able to give written informed consent.

Exclusion criteria

* Prior exposure to cG250 monoclonal antibody (exception: no circulating human anti-chimeric antibody to cG250). * Prior treatment with vascular endothelial growth factor (VEGF)-targeting agents (e.g. bevacizumab) or multi-kinase inhibitors (e.g. sorafenib) not including sunitinib. (Patients currently receiving sunitinib may be eligible if tolerating a stable dose of sunitinib on a four week on / two week off regimen, with toxicity due to sunitinib ≤ CTCAE grade 2; and for whom the investigator deems it clinically reasonable to withhold sunitinib for at least four weeks prior to commencement of study treatment.) * Active central nervous system (CNS) metastases (exception: CNS metastases adequately treated (surgery or radiotherapy) with no progression for at least three months). * Known HIV positivity. * Clinically significant heart disease. * History of hypertension requiring hospitalisation. * Other serious illnesses, eg, serious infections requiring antibiotics, bleeding disorders. * Major surgery or radiation therapy within 4 weeks prior to, or planned within 6 weeks of starting the study treatment. (Prior palliative radiotherapy to metastatic lesion(s) permitted, provided at least one measurable lesion was not irradiated or has progressed following radiotherapy.) * Severe haemorrhage within 4 weeks prior to starting the study treatment. * Any of the following within the 12 months prior to study drug administration: myocardial infarction, severe/unstable angina, coronary/peripheral artery bypass graft, symptomatic congestive heart failure, cerebrovascular accident or transient ischemic attack, or pulmonary embolism. * Pre-existing thyroid abnormality with unstable thyroid function despite medication. * Ongoing moderate to severe cardiac dysrhythmias, any severity of atrial fibrillation, or prolongation of the corrected QT interval (QTc) to greater than 450 millisecond for males or 470 millisecond for females. * Participation in a clinical trial involving another investigational agent within 4 weeks. * Pregnancy or breastfeeding. * Women of childbearing potential not using a medically acceptable means of contraception. * Psychiatric or addictive disorders that may compromise the ability to give informed consent. * Not available for follow-up assessment.

Design outcomes

Primary

MeasureTime frameDescription
Number of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.up to 14 weeksToxicity was graded in accordance with the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. Adverse events (AEs) were reported based on clinical laboratory tests, vital sign, weight measurements, physical examinations, and performance status evaluations. Pre-existing symptoms were collected from the signing of informed consent until the first dose of study drug. Adverse events were collected from the first dose of study drug through the end of study assessment. Dose Limiting Toxicity (DLT): any of the following events occurring within 30 days of study drug administration related to cG250 or sunitinib. Grade 2 or greater allergic reaction. Grade 3 toxicity. Exceptions are: fever; asymptomatic hyperglycemia; hypophosphatemia; nausea, vomiting, or diarrhoea that resolve with medical therapy; leukopenia or thrombocytopenia that revert to baseline within three weeks of occurrence, or lymphopenia only. Any Grade 4 toxicity.

Secondary

MeasureTime frameDescription
Number of Patients With Tumor Metabolic Response as Assessed by Serial 18F-FDG-PET Scans.7 weeks18F-FDG-PET was performed at pre-study, between days 15-22 and at the end of cycle 1. At baseline, visual grading of the intensity of FDG uptake was scored. On follow-up PET scans, the greatest baseline maximum standard uptake value (SUVmax) of the reference lesion with the greatest baseline value and presence/absence of new sites of disease were recorded. Tumour metabolic response was calculated using the SUVmax and was categorized according to the EORTC guidelines (Young et al 1999). Complete metabolic remission (CMR) is the disappearance of tracer uptake in the target lesion and no new lesions; Partial metabolic remission (PMR) is a 20% or more decrease in the tracer uptake in the target lesion and no new lesions; Tumor progression was defined as a greater than 20% increase in FDG uptake or the appearance of new tumour lesions. Stable metabolic disease (SMD) was classified as no significant change in uptake.
Whole Body Clearance as Measured by Mean Biological Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.7 weeksBiological half-life is the clearance of the 124I from the whole body. Positron emission tomography (PET) imaging was performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-2-fluoro-2-deoxy-D-glucose fluorodeoxyglucose (18F-FDG) PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Whole body clearance of 124I-cG250 was calculated from the whole body PET volumetric images, obtained at the multiple imaging time points after infusion. VOIs were delineated to encompass the whole body regions in the images, and for the whole-body VOI at each time point, the total counts per minute was normalized to the first imaging time point on Day 1.
Whole Body Clearance as Measured by Mean Effective Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.7 weeksEffective half-life is the time it takes the radiolabel to be reduced by 50%. This takes into account the biological elimination and the radioactive decay of the 124I. PET imaging studies were performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Whole body clearance of 124I-cG250 was calculated from the whole body PET volumetric images, obtained at the multiple imaging time points after infusion. VOIs were delineated to encompass the whole body regions in the images, and for the whole-body VOI at each time point, the total counts per minute was normalized to the first imaging time point on Day 1.
Number of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.7 weeksPET imaging studies were performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging.
Serum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.7 weeksBlood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).
Number of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).up to 14 weeksTumor responses were evaluated using appropriate imaging and categorized according to RECIST at Screening (within 4 weeks of the first dose of study treatment), and after cycles 1 and 2 of study treatment. Per RECIST, target lesions are categorized as follows: complete response (CR): disappearance of all target lesions; partial response (PR): ≥ 30% decrease in the sum of the longest diameter of target lesions; progressive disease (PD): ≥ 20% increase in the sum of the longest diameter of target lesions; stable disease (SD): small changes that do not meet above criteria (Therasse et al 2000).
Serum Pharmacokinetics as Measured by Mean Area Under the Concentration Curve Extrapolated to Infinite Time (AUC) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.7 weeksBlood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).
Serum Pharmacokinetics as Measured by Mean Total Serum Clearance (CL) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.7 weeksBlood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).
Serum Pharmacokinetics as Measured by Mean Maximum Serum Concentration (Cmax) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.7 weeksBlood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).
Number of Patients With Decreases in Tumour Blood Flow on Week 3 Versus Baseline.7 weeks15O-H2O PET scans were performed up to 14 days prior to treatment and between days 15-22 in the first treatment cycle only. Approximately 750 megabecquerel (MBq) of 15O-H2O were administered intravenously and data was acquired dynamically over 5-10 minutes. The PET scan field of view was of an anatomical region containing a least one reference tumour lesion. Quantitation of blood flow within tumour was performed, and expressed in mL/mg/min. Follow-up 15O-H2O PET scan quantitated blood flow within the same reference lesion(s), allowing direct comparison of any change in quantitative tumour blood flow in response to treatment to be measured.
Number of Patients With Human Anti-chimeric Antibodies (HACA)7 - 14 weeksBlood samples (5 mL/sample) were drawn prior to each cG250 or 124I-cG250 infusion during cycle 1 and also at the End of Study visit. If a second cycle of treatment was administered, HACA was performed at the End of Study visit. The immunochemical measurement of anti-cG250 antibodies in human serum was performed by an enzyme-linked immunosorbent assay (ELISA). Samples with values greater than the limit of quantitation (16 ng/mL) were considered HACA positive. Samples at or below that level were reported as negative.
Serum Pharmacokinetics as Measured by Mean Volume of Central Compartment (V1) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.7 weeksBlood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Countries

Australia

Participant flow

Recruitment details

8 patients were recruited and signed informed consent; 2 patients were withdrawn prior to receiving study treatment. (One patient was withdrawn from the study because of requiring urgent radiotherapy and the other withdrew consent.) Six patients were enrolled and received study treatment. The study was terminated for safety reasons.

Participants by arm

ArmCount
cG250 + Sunitinib
Treatment (cycle 1): * cG250 10mg/m² IV weekly x 5 doses (1st & 5th doses trace-labelled with 124I) * Sunitinib 50 mg/day orally x 4 weeks commencing day 8 * Followed by two-week break Treatment (cycle 2 - investigator discretion): * cG250 10mg/m² IV weekly x4 doses * Sunitinib 50 mg/day orally x 4 weeks (commencing concurrently) * Followed by two-week break Up to 2 cycles available on-study.
6
Total6

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyDeath1
Overall StudyPhysician Decision1
Overall StudySuspension of the study for safety reasons1
Overall StudyWithdrawal by Subject1

Baseline characteristics

CharacteristiccG250 + Sunitinib
Age, Continuous64.3 years
STANDARD_DEVIATION 9.913
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
6 Participants
Region of Enrollment
Australia
6 participants
Sex: Female, Male
Female
2 Participants
Sex: Female, Male
Male
4 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
1 / 6
other
Total, other adverse events
6 / 6
serious
Total, serious adverse events
3 / 6

Outcome results

Primary

Number of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.

Toxicity was graded in accordance with the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. Adverse events (AEs) were reported based on clinical laboratory tests, vital sign, weight measurements, physical examinations, and performance status evaluations. Pre-existing symptoms were collected from the signing of informed consent until the first dose of study drug. Adverse events were collected from the first dose of study drug through the end of study assessment. Dose Limiting Toxicity (DLT): any of the following events occurring within 30 days of study drug administration related to cG250 or sunitinib. Grade 2 or greater allergic reaction. Grade 3 toxicity. Exceptions are: fever; asymptomatic hyperglycemia; hypophosphatemia; nausea, vomiting, or diarrhoea that resolve with medical therapy; leukopenia or thrombocytopenia that revert to baseline within three weeks of occurrence, or lymphopenia only. Any Grade 4 toxicity.

Time frame: up to 14 weeks

Population: All patients who received at least one dose of cG250.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.Number of Patients With at least 1 AE6 Participants
cG250 and SunitinibNumber of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.Number of Patients With at Least 1 Serious AE3 Participants
cG250 and SunitinibNumber of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.Number of Patients With a DLT2 Participants
cG250 and SunitinibNumber of Patients With Adverse Events (AEs), Serious Adverse Events (SAEs), Dose Limiting Toxicities (DLTs) or Adverse Events Leading to Discontinuation.Number of Patients with an AE leading to treatment discontinuation1 Participants
Secondary

Number of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.

PET imaging studies were performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging.

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the tumour uptake after the fifth infusion of 124I-cG250.

ArmMeasureGroupCategoryValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.First InfusionTumor uptake6 Participants
cG250 and SunitinibNumber of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.First InfusionNo Tumor uptake0 Participants
cG250 and SunitinibNumber of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.Fifth InfusionTumor uptake4 Participants
cG250 and SunitinibNumber of Patients With 124I-cG250 Tumor Uptake After the First and Fifth Infusions of 124I-cG250.Fifth InfusionNo Tumor uptake0 Participants
Secondary

Number of Patients With Decreases in Tumour Blood Flow on Week 3 Versus Baseline.

15O-H2O PET scans were performed up to 14 days prior to treatment and between days 15-22 in the first treatment cycle only. Approximately 750 megabecquerel (MBq) of 15O-H2O were administered intravenously and data was acquired dynamically over 5-10 minutes. The PET scan field of view was of an anatomical region containing a least one reference tumour lesion. Quantitation of blood flow within tumour was performed, and expressed in mL/mg/min. Follow-up 15O-H2O PET scan quantitated blood flow within the same reference lesion(s), allowing direct comparison of any change in quantitative tumour blood flow in response to treatment to be measured.

Time frame: 7 weeks

Population: Number of patients who received 15O-H2O PET scans at baseline and between days 15-22. One patient did not receive the 15O-H2O PET scans due to technical problems.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With Decreases in Tumour Blood Flow on Week 3 Versus Baseline.5 Participants
Secondary

Number of Patients With Human Anti-chimeric Antibodies (HACA)

Blood samples (5 mL/sample) were drawn prior to each cG250 or 124I-cG250 infusion during cycle 1 and also at the End of Study visit. If a second cycle of treatment was administered, HACA was performed at the End of Study visit. The immunochemical measurement of anti-cG250 antibodies in human serum was performed by an enzyme-linked immunosorbent assay (ELISA). Samples with values greater than the limit of quantitation (16 ng/mL) were considered HACA positive. Samples at or below that level were reported as negative.

Time frame: 7 - 14 weeks

Population: All patients who had one cG250 pre-treatment and at least one post-treatment sample taken.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With Human Anti-chimeric Antibodies (HACA)Number of patients with positive HACA0 Participants
cG250 and SunitinibNumber of Patients With Human Anti-chimeric Antibodies (HACA)Number of patients with negative HACA6 Participants
Secondary

Number of Patients With Tumor Metabolic Response as Assessed by Serial 18F-FDG-PET Scans.

18F-FDG-PET was performed at pre-study, between days 15-22 and at the end of cycle 1. At baseline, visual grading of the intensity of FDG uptake was scored. On follow-up PET scans, the greatest baseline maximum standard uptake value (SUVmax) of the reference lesion with the greatest baseline value and presence/absence of new sites of disease were recorded. Tumour metabolic response was calculated using the SUVmax and was categorized according to the EORTC guidelines (Young et al 1999). Complete metabolic remission (CMR) is the disappearance of tracer uptake in the target lesion and no new lesions; Partial metabolic remission (PMR) is a 20% or more decrease in the tracer uptake in the target lesion and no new lesions; Tumor progression was defined as a greater than 20% increase in FDG uptake or the appearance of new tumour lesions. Stable metabolic disease (SMD) was classified as no significant change in uptake.

Time frame: 7 weeks

Population: All patients who received at least one dose of cG250, completed cycle 1 and were evaluable for tumor metabolic response.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With Tumor Metabolic Response as Assessed by Serial 18F-FDG-PET Scans.CMR1 Participants
cG250 and SunitinibNumber of Patients With Tumor Metabolic Response as Assessed by Serial 18F-FDG-PET Scans.PMR0 Participants
cG250 and SunitinibNumber of Patients With Tumor Metabolic Response as Assessed by Serial 18F-FDG-PET Scans.SMD3 Participants
Secondary

Number of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).

Tumor responses were evaluated using appropriate imaging and categorized according to RECIST at Screening (within 4 weeks of the first dose of study treatment), and after cycles 1 and 2 of study treatment. Per RECIST, target lesions are categorized as follows: complete response (CR): disappearance of all target lesions; partial response (PR): ≥ 30% decrease in the sum of the longest diameter of target lesions; progressive disease (PD): ≥ 20% increase in the sum of the longest diameter of target lesions; stable disease (SD): small changes that do not meet above criteria (Therasse et al 2000).

Time frame: up to 14 weeks

Population: All patients who received at least one dose of cG250.and were evaluable for tumour response.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
cG250 and SunitinibNumber of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).Complete Response (CR)0 Participants
cG250 and SunitinibNumber of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).Partial Response (PR)1 Participants
cG250 and SunitinibNumber of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).Stable Disease (SD)3 Participants
cG250 and SunitinibNumber of Patients With Tumour Response Assessed by Response Evaluation Criteria in Solid Tumors (RECIST).Progressive Disease (PD)0 Participants
Secondary

Serum Pharmacokinetics as Measured by Mean Area Under the Concentration Curve Extrapolated to Infinite Time (AUC) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.

Blood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included the fifth infusion results. Two patients were not included in the ELISA analysis due to a disproportionate effect on the estimated parameter.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Area Under the Concentration Curve Extrapolated to Infinite Time (AUC) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.AUC as measured by blood 124I radioactivity after the first infusion520 hours*mcg/mLStandard Deviation 153
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Area Under the Concentration Curve Extrapolated to Infinite Time (AUC) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.AUC as measured by blood 124I radioactivity after the fifth infusion682 hours*mcg/mLStandard Deviation 240
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Area Under the Concentration Curve Extrapolated to Infinite Time (AUC) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.AUC as measured by ELISA after the first infusion759 hours*mcg/mLStandard Deviation 335
Secondary

Serum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.

Blood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the fifth infusion results. Two patients were not included in the T½ β ELISA analysis due to a disproportionate effect on the estimated parameter.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½ α as measured by blood 124I radioactivity after the first infusion9.83 hoursStandard Deviation 8.63
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½ β as measured by blood 124I radioactivity after the first infusion104.1 hoursStandard Deviation 52.2
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½α as measured by ELISA after the first infusion27.7 hoursStandard Deviation 34.4
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½ β as measured by ELISA after the first infusion105.2 hoursStandard Deviation 52.2
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½ α as measured by blood 124I radioactivity after the fifth infusion18.54 hoursStandard Deviation 14.04
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Initial Half-life (T½ α) and Mean Terminal Half-life (T½ β) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.T½ β as measured by blood 124I radioactivity after the fifth infusion146.9 hoursStandard Deviation 69.2
Secondary

Serum Pharmacokinetics as Measured by Mean Maximum Serum Concentration (Cmax) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.

Blood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the fifth infusion results.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Maximum Serum Concentration (Cmax) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.Cmax as measured by blood 124I radioactivity after the first infusion5.93 mcg/mLStandard Deviation 1.06
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Maximum Serum Concentration (Cmax) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.Cmax as measured by blood 124I radioactivity after the fifth infusion6.661 mcg/mLStandard Deviation 0.678
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Maximum Serum Concentration (Cmax) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.Cmax as measured by ELISA after the first infusion7.57 mcg/mLStandard Deviation 1.88
Secondary

Serum Pharmacokinetics as Measured by Mean Total Serum Clearance (CL) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.

Blood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the fifth infusion results. Two patients were not included in the ELISA analysis due to a disproportionate effect on the estimated parameter.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Total Serum Clearance (CL) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.CL as measured by blood 124I radioactivity after the first infusion38.7 mL/hourStandard Deviation 19.7
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Total Serum Clearance (CL) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.CL as measured by blood 124I radioactivity after the fifth infusion28.7 mL/hourStandard Deviation 15.7
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Total Serum Clearance (CL) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.CL as measured by ELISA after the first infusion25.7 mL/hourStandard Deviation 17.5
Secondary

Serum Pharmacokinetics as Measured by Mean Volume of Central Compartment (V1) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.

Blood samples were taken prior to 124I-cG250 infusion and 5 minutes, 1, 2, 4 and 24 hours post 124I-cG250 infusion. The pharmacokinetics of 124I-cG250 were calculated using gamma scintillation counting and by enzyme-linked immunosorbent assay (ELISA).

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the fifth infusion results.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Volume of Central Compartment (V1) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.V1 as measured by blood 124I radioactivity after the first infusion3067 mLStandard Deviation 705
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Volume of Central Compartment (V1) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.V1 as measured by blood 124I radioactivity after the fifith infusion2542 mLStandard Deviation 267
cG250 and SunitinibSerum Pharmacokinetics as Measured by Mean Volume of Central Compartment (V1) After the First and Fifth Infusions of 124I-cG250 as Measured by Blood 124I Radioactivity and After the First Dose as Measured by ELISA.V1 as measured by ELISA after the first infusion2286 mLStandard Deviation 678
Secondary

Whole Body Clearance as Measured by Mean Biological Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.

Biological half-life is the clearance of the 124I from the whole body. Positron emission tomography (PET) imaging was performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-2-fluoro-2-deoxy-D-glucose fluorodeoxyglucose (18F-FDG) PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Whole body clearance of 124I-cG250 was calculated from the whole body PET volumetric images, obtained at the multiple imaging time points after infusion. VOIs were delineated to encompass the whole body regions in the images, and for the whole-body VOI at each time point, the total counts per minute was normalized to the first imaging time point on Day 1.

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the Week 5 results.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibWhole Body Clearance as Measured by Mean Biological Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.Biological T1/2 Week 1121.12 daysStandard Deviation 20.68
cG250 and SunitinibWhole Body Clearance as Measured by Mean Biological Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.Biological T1/2 Week 5149.12 daysStandard Deviation 42.52
Comparison: Comparison of Biological T1/2 at Week 1 and Week 5.p-value: 0.194t-test, 2 sided
Secondary

Whole Body Clearance as Measured by Mean Effective Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.

Effective half-life is the time it takes the radiolabel to be reduced by 50%. This takes into account the biological elimination and the radioactive decay of the 124I. PET imaging studies were performed at 1 - 4 hours post infusion, and at two other time points over the ensuing one-week period. Quantitative uptakes of 124I-cG250 were assessed in one selected reference tumour lesion identified by 18F-FDG-PET imaging. Tumour volume of Interest (VOI) was delineated around the whole tumour mass on the consecutive transverse slices of FDG-PET/CT images at which the tumours were most clearly identified. Whole body clearance of 124I-cG250 was calculated from the whole body PET volumetric images, obtained at the multiple imaging time points after infusion. VOIs were delineated to encompass the whole body regions in the images, and for the whole-body VOI at each time point, the total counts per minute was normalized to the first imaging time point on Day 1.

Time frame: 7 weeks

Population: All patients who received the first and fifth infusion of 124I-cG250. Two patients received the first infusion but not the fifth infusion and as a result were not included in the Week 5 results.

ArmMeasureGroupValue (MEAN)Dispersion
cG250 and SunitinibWhole Body Clearance as Measured by Mean Effective Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.Effective T1/2 Week 154.46 hoursStandard Deviation 5
cG250 and SunitinibWhole Body Clearance as Measured by Mean Effective Half-life (T1/2) After the First and Fifth Infusions of 124I-cG250.Effective T1/2 Week 559.15 hoursStandard Deviation 6.4
Comparison: Comparison of Effective T1/2 at Week 1 and Week 5.p-value: 0.172t-test, 2 sided

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026