Joachim Feldwisch - Academia.edu (original) (raw)
Papers by Joachim Feldwisch
Proceedings of SPIE, the International Society for Optical Engineering, Mar 4, 2019
Microdose administration of ABY-029, an anti-epidermal growth factor receptor Affibody molecule c... more Microdose administration of ABY-029, an anti-epidermal growth factor receptor Affibody molecule conjugated to IRDye 800CW, is being studied in a Phase 0 trial for resection of soft-tissue sarcomas. The excised tissue of a single patient in the microdose administration group was imaged with both a wide-field fluorescence surgical system and a flat-bed scanning fluorescence imaging system. Here the resultant fluorescence from a breadloaf section of the primary tumor specimen and six region-specific tissue samples collected from that breadloaf are compared using these two imaging systems - a flatbed, black-box, fluorescence scanning system, the Odyssey CLx, and a open-air, wide-field, pre-clinical surgical imaging system, the Solaris. Florescence signal is compared using a variety of methods including: mean, standard deviation, variance, tumor-to-background ratio, biological-variance ratio, and contrast-to-noise ratio. The images produced from the Odyssey scanner have higher signal var...
The clinical utility of a human epidermal growth factor receptor 2 (HER2)–targeting Affibody mole... more The clinical utility of a human epidermal growth factor receptor 2 (HER2)–targeting Affibody molecule for detection and character-ization ofHER2-positive lesions was investigated in patients with recurrent metastatic breast cancer. Methods: Three patients re-ceived 111In- or 68Ga-labeled DOTA0-ZHER2:342-pep2 (ABY-002). g-Camera, SPECT, or PET/CT images were compared with ear-lier 18F-FDG PET/CT results. Results: Administration of radiola-beled ABY-002 was well tolerated. Blood kinetics of radiolabeled ABY-002 showed a first half-life of 4–14 min, second half-life of 1–4 h, and third half-life of 12–18 h. Radiolabeled ABY-002 detected 9 of 11 18F-FDG–positive metastases as early as 2–3 h after injection. Conclusion: Molecular imaging using 111In- or 68Ga-labeled ABY-002 has the potential to localize metastatic lesions in vivo, adds qualitative information not available today by conventional imaging techniques, and may allow the HER2 status to be determined for metastases not amenable...
The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tum... more The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tumors provides important infor-mation influencing patient management. Radionuclide in vivo imaging of HER2 may permit the detection of HER2 in both pri-mary tumors andmetastases by a single noninvasive procedure. Small (7 kDa) high-affinity anti-HER2 Affibody molecules may be suitable tracers for SPECT visualization of HER2-expressing tu-mors. The use of generator-produced 99mTc as a label would fa-cilitate the prompt translation of anti-HER2 Affibody molecules into use in clinics. Methods: A C-terminal cysteine was introduced into the Affibody molecule ZHER2:342 to enable site-specific labeling with 99mTc. Two recombinant variants, His6-ZHER2:342-Cys (dissociation constant [KD], 29 pM) and ZHER2:2395-Cys, lacking a His tag (KD, 27 pM), were labeled with 99mTc in yields exceeding 90%. The binding specificity and the
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](Purpose: Positron Emission Tomography (PET) imaging of HER2 expression could potentially be used ... more Purpose: Positron Emission Tomography (PET) imaging of HER2 expression could potentially be used to select patients for HER2-targed therapy, predict response based on uptake and be used for monitoring. In this phase I/II study the HER2-binding Affibody molecule ABY-025 was labeled with 68 Ga-gallium ([ 68 Ga]ABY-025) for PET to study effect of peptide mass, test-retest variability and correlation of quantified uptake in tumors to histopathology. Experimental design: Sixteen women with known metastatic breast cancer and on-going treatment were included and underwent FDG PET/CT to identify viable metastases. After iv injection of 212±46 MBq [ 68 Ga]ABY-025 whole-body PET was performed at 1, 2 and 4 h. In the first 10 patients (6 with HER2-positive and 4 with HER2-negative primary tumors), [ 68 Ga]ABY-025 PET/CT with two different doses of injected peptide was performed one week apart. In the last six patients (5 HER2-positive and 1 HER2-negative primary tumors), repeated [ 68 Ga]ABY-0...
American journal of nuclear medicine and molecular imaging, 2019
[68Ga]Ga-ABY-025/PET-CT targeting human epidermal growth factor receptor type 2 (HER2) has demons... more [68Ga]Ga-ABY-025/PET-CT targeting human epidermal growth factor receptor type 2 (HER2) has demonstrated its potential clinical value for the detection and quantification of HER2 in a phase I clinical study with breast cancer patients. Previously, the radiopharmaceutical was prepared manually, however larger scale of multicenter clinical trials and routine healthcare requires automation of the production process to limit the operator radiation dose, improve tracer manufacturing robustness, and provide on-line documentation for good manufacturing practice (GMP) compliance. The production of [68Ga]Ga-ABY-025 was implemented on the Modular-Lab PharmTrace synthesis platform (Eckert & Ziegler) and disposable cassettes were developed. Pharmaceutical grade 68Ge/68Ga generator (GalliaPharm®) was used in the study. The active pharmaceutical ingredient starting material ABY-025 (GMP grade) was provided by Affibody AB. The patient examinations were conducted using a Discovery MI PET/CT scanner (20 cm FOV, GE Healthcare). Reproducible and GMP compliant fully automated production of [68Ga]Ga-ABY-025 was developed. The radiochemical purity of the product was 98.7 ± 0.6% with total peptide content of 315 ± 15 µg (n = 3). Radionuclidic purity, sterility, endotoxin content, residual solvent content, and sterile filter integrity were controlled and met acceptance criteria. The product was stable at ambient temperature for at least 2 h. The primary tumor and metastasis were detected with SUVmax values of 8.3 and 16.0, respectively. Automated production of [68Ga]Ga-ABY-025 was established and the process was validated enabling standardized multicenter phase II and III clinical trials and routine clinical use. Patient examinations conformed to the radiopharmaceutical biodistribution observed in the previous phase I study.
Molecular-Guided Surgery: Molecules, Devices, and Applications VII
European Journal of Nuclear Medicine and Molecular Imaging, 2010
European Journal of Nuclear Medicine and Molecular Imaging, 2014
Accuracy of [Ga-68]ABY-025 PET/CT for determination of HER2-expression in metastatic breast cancer
Journal of Clinical Oncology
Non-invasive determination of HER2-expression in metastatic breast cancer by using Ga-68-ABY025 P... more Non-invasive determination of HER2-expression in metastatic breast cancer by using Ga-68-ABY025 PET/CT.
EJNMMI Research
Background High expression of human epidermal growth factor receptor type 2 (HER2) represents an ... more Background High expression of human epidermal growth factor receptor type 2 (HER2) represents an aggressive subtype of breast cancer. Anti-HER2 treatment requires a theragnostic approach wherein sufficiently high receptor expression in biopsy material is mandatory. Heterogeneity and discordance of HER2 expression between primary tumour and metastases, as well as within a lesion, present a complication for the treatment and require multiple biopsies. Molecular imaging using the HER2-targeting Affibody peptide ABY-025 radiolabelled with 68Ga-gallium for PET/CT is currently under investigation as a non-invasive tool for whole-body evaluation of metastatic HER2 expression. Initial studies demonstrated a high correlation between 68Ga-ABY-025 standardized uptake values (SUVs) and histopathology. However, detecting small liver lesions might be compromised by high background uptake. This study aimed to explore the applicability of kinetic modelling and parametric image analysis for absolute...
Journal of Surgical Oncology
Fluorescence‐guided surgery using epidermal growth factor receptor (EGFR) targeting has been perf... more Fluorescence‐guided surgery using epidermal growth factor receptor (EGFR) targeting has been performed successfully in clinical trials using a variety of fluorescent agents. We investigate ABY‐029 (anti‐EGFR Affibody® molecule labeled with IRDye 800CW) compared with a small‐molecule perfusion agent, IRDye 700DX carboxylate, in a panel of soft‐tissue sarcomas with varying levels of EGFR expression and vascularization.
Cancer control : journal of the Moffitt Cancer Center
The excision of tumors by wide local excision is challenging because the mass must be removed ent... more The excision of tumors by wide local excision is challenging because the mass must be removed entirely without ever viewing it directly. Positive margin rates in sarcoma resection remain in the range of 20% to 35% and are associated with increased recurrence and decreased survival. Fluorescence-guided surgery (FGS) may improve surgical accuracy and has been utilized in other surgical specialties. ABY-029, an anti-epidermal growth factor receptor Affibody molecule covalently bound to the near-infrared fluorophore IRDye 800CW, is an excellent candidate for future FGS applications in sarcoma resection; however, conventional methods with direct surface tumor visualization are not immediately applicable. A novel technique involving imaging through a margin of normal tissue is needed. We review the past and present applications of FGS and present a novel concept of indirect FGS for visualizing tumor through a margin of normal tissue and aiding in excising the entire lesion as a single, co...
European Journal of Nuclear Medicine and Molecular Imaging, 2017
In phase I/II-studies radiolabelled ABY-025 Affibody molecules identified human epidermal growth ... more In phase I/II-studies radiolabelled ABY-025 Affibody molecules identified human epidermal growth factor receptor 2 (HER2) expression in breast cancer metastases using PET and SPECT imaging. Here, we wanted to investigate the utility of a simple intra-image normalization using tumour-to-reference tissue-ratio (T/R) as a HER2 status discrimination strategy to overcome potential issues related to cross-calibration of scanning devices. Methods Twenty-three women with pre-diagnosed HER2positive/negative metastasized breast cancer were scanned with [ 111 In]-ABY-025 SPECT/CT (n = 7) or [ 68 Ga]-ABY-025 PET/CT (n = 16). Uptake was measured in all metastases and in normal spleen, lung, liver, muscle, and blood pool. Normal tissue uptake variation and T/R-ratios were established for various time points and for two different doses of injected peptide from a total of 94 whole-body image acquisitions. Immunohistochemistry (IHC) was used to verify HER2 expression in 28 biopsied metastases. T/R-ratios were compared to IHC findings to establish the best reference tissue for each modality and each imaging time-point. The impact of shed HER2 in serum was investigated. Results Spleen was the best reference tissue across modalities, followed by blood pool and lung. Spleen-T/R was highly correlated to PET SUV in metastases after 2 h (r = 0.96, P < 0.001) and reached an accuracy of 100% for discriminating IHC HER2-positive and negative metastases at 4 h (PET) and 24 h (SPECT) after injection. In a single case, shed HER2 resulted in intense tracer retention in blood. In the remaining patients shed HER2 was elevated, but without significant impact on ABY-025 biodistribution. Conclusion T/R-ratios using spleen as reference tissue accurately quantify HER2 expression with radiolabelled ABY-025 imaging in breast cancer metastases with SPECT and PET. Tracer binding to shed HER2 in serum might affect quantification in the extreme case.
Molecular Imaging and Biology, 2016
ABY-029, a synthetic Affibody peptide, Z03115-Cys, labeled with a near-infrared fluorophore, IRDy... more ABY-029, a synthetic Affibody peptide, Z03115-Cys, labeled with a near-infrared fluorophore, IRDye® 800CW, targeting epidermal growth factor receptor (EGFR) has been produced under good manufacturing practices for a US Food and Drug Administration-approved first-in-use human study during surgical resection of glioma, as well as other tumors. Here, the pharmacology, phototoxicity, receptor activity, and biodistribution studies of ABY-029 were completed in rats, prior to the intended human use. Male and female Sprague Dawley rats were administered a single intravenous dose of varying concentrations (0, 245, 2449, and 24,490 μg/kg corresponding to 10×, 100×, and 1000× an equivalent human microdose level) of ABY-029 and observed for up to 14 days. Histopathological assessment of organs and tissues, clinical chemistry, and hematology were performed. In addition, pharmacokinetic clearance and biodistribution of ABY-029 were studied in subgroups of the animals. Phototoxicity and ABY-029 binding to human and rat EGFR were assessed in cell culture and on immobilized receptors, respectively. Histopathological assessment and hematological and clinical chemistry analysis demonstrated that single-dose ABY-029 produced no pathological evidence of toxicity at any dose level. No phototoxicity was observed in EGFR-positive and EGFR-negative glioma cell lines. Binding strength and pharmacokinetics of the anti-EGFR Affibody molecules were retained after labeling with the dye. Based on the successful safety profile of ABY-029, the 1000× human microdose 24.5 mg/kg was identified as the no observed adverse effect level following intravenous administration. Conserved binding strength and no observed light toxicity also demonstrated ABY-029 safety for human use.
Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 31, 2016
While extent of tumor resection is an important predictor of outcome in glioma, margin delineatio... more While extent of tumor resection is an important predictor of outcome in glioma, margin delineation remains challenging due to lack of inherent contrast between tumor and normal parenchyma. Fluorescence-guided surgery is promising for its ability to enhance contrast through exogenous fluorophores, however, the specificity and sensitivity of the underlying contrast mechanism and tumor delivery and uptake vary widely across approved and emerging agents. Rats with orthotopic F98 wild-type and F98 EGFR-positive gliomas received in vivo administration of IRDye680RD, 5-aminioleuvulinic acid, and ABY-029-markers of perfusion, protoporphyrin metabolism, and EGFR expression, respectively. Ex vivo imaging demonstrates the contrast mechanism-dependent spatial heterogeneity and enables within-animal comparisons of tumor-to-background ratio (TBR). Generally, ABY-029 outperformed PpIX in F98EGFR orthotopic tumor margins and core (50% and 60% higher TBR, respectively). PpIX outperformed ABY-029 in ...
Society of Nuclear Medicine Annual Meeting Abstracts, May 1, 2012
Proceedings of SPIE, the International Society for Optical Engineering, Mar 4, 2019
Microdose administration of ABY-029, an anti-epidermal growth factor receptor Affibody molecule c... more Microdose administration of ABY-029, an anti-epidermal growth factor receptor Affibody molecule conjugated to IRDye 800CW, is being studied in a Phase 0 trial for resection of soft-tissue sarcomas. The excised tissue of a single patient in the microdose administration group was imaged with both a wide-field fluorescence surgical system and a flat-bed scanning fluorescence imaging system. Here the resultant fluorescence from a breadloaf section of the primary tumor specimen and six region-specific tissue samples collected from that breadloaf are compared using these two imaging systems - a flatbed, black-box, fluorescence scanning system, the Odyssey CLx, and a open-air, wide-field, pre-clinical surgical imaging system, the Solaris. Florescence signal is compared using a variety of methods including: mean, standard deviation, variance, tumor-to-background ratio, biological-variance ratio, and contrast-to-noise ratio. The images produced from the Odyssey scanner have higher signal var...
The clinical utility of a human epidermal growth factor receptor 2 (HER2)–targeting Affibody mole... more The clinical utility of a human epidermal growth factor receptor 2 (HER2)–targeting Affibody molecule for detection and character-ization ofHER2-positive lesions was investigated in patients with recurrent metastatic breast cancer. Methods: Three patients re-ceived 111In- or 68Ga-labeled DOTA0-ZHER2:342-pep2 (ABY-002). g-Camera, SPECT, or PET/CT images were compared with ear-lier 18F-FDG PET/CT results. Results: Administration of radiola-beled ABY-002 was well tolerated. Blood kinetics of radiolabeled ABY-002 showed a first half-life of 4–14 min, second half-life of 1–4 h, and third half-life of 12–18 h. Radiolabeled ABY-002 detected 9 of 11 18F-FDG–positive metastases as early as 2–3 h after injection. Conclusion: Molecular imaging using 111In- or 68Ga-labeled ABY-002 has the potential to localize metastatic lesions in vivo, adds qualitative information not available today by conventional imaging techniques, and may allow the HER2 status to be determined for metastases not amenable...
The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tum... more The detection of human epidermal growth factor receptor type 2 (HER2) expression in malignant tumors provides important infor-mation influencing patient management. Radionuclide in vivo imaging of HER2 may permit the detection of HER2 in both pri-mary tumors andmetastases by a single noninvasive procedure. Small (7 kDa) high-affinity anti-HER2 Affibody molecules may be suitable tracers for SPECT visualization of HER2-expressing tu-mors. The use of generator-produced 99mTc as a label would fa-cilitate the prompt translation of anti-HER2 Affibody molecules into use in clinics. Methods: A C-terminal cysteine was introduced into the Affibody molecule ZHER2:342 to enable site-specific labeling with 99mTc. Two recombinant variants, His6-ZHER2:342-Cys (dissociation constant [KD], 29 pM) and ZHER2:2395-Cys, lacking a His tag (KD, 27 pM), were labeled with 99mTc in yields exceeding 90%. The binding specificity and the
Purpose: Positron Emission Tomography (PET) imaging of HER2 expression could potentially be used ... more Purpose: Positron Emission Tomography (PET) imaging of HER2 expression could potentially be used to select patients for HER2-targed therapy, predict response based on uptake and be used for monitoring. In this phase I/II study the HER2-binding Affibody molecule ABY-025 was labeled with 68 Ga-gallium ([ 68 Ga]ABY-025) for PET to study effect of peptide mass, test-retest variability and correlation of quantified uptake in tumors to histopathology. Experimental design: Sixteen women with known metastatic breast cancer and on-going treatment were included and underwent FDG PET/CT to identify viable metastases. After iv injection of 212±46 MBq [ 68 Ga]ABY-025 whole-body PET was performed at 1, 2 and 4 h. In the first 10 patients (6 with HER2-positive and 4 with HER2-negative primary tumors), [ 68 Ga]ABY-025 PET/CT with two different doses of injected peptide was performed one week apart. In the last six patients (5 HER2-positive and 1 HER2-negative primary tumors), repeated [ 68 Ga]ABY-0...
American journal of nuclear medicine and molecular imaging, 2019
[68Ga]Ga-ABY-025/PET-CT targeting human epidermal growth factor receptor type 2 (HER2) has demons... more [68Ga]Ga-ABY-025/PET-CT targeting human epidermal growth factor receptor type 2 (HER2) has demonstrated its potential clinical value for the detection and quantification of HER2 in a phase I clinical study with breast cancer patients. Previously, the radiopharmaceutical was prepared manually, however larger scale of multicenter clinical trials and routine healthcare requires automation of the production process to limit the operator radiation dose, improve tracer manufacturing robustness, and provide on-line documentation for good manufacturing practice (GMP) compliance. The production of [68Ga]Ga-ABY-025 was implemented on the Modular-Lab PharmTrace synthesis platform (Eckert & Ziegler) and disposable cassettes were developed. Pharmaceutical grade 68Ge/68Ga generator (GalliaPharm®) was used in the study. The active pharmaceutical ingredient starting material ABY-025 (GMP grade) was provided by Affibody AB. The patient examinations were conducted using a Discovery MI PET/CT scanner (20 cm FOV, GE Healthcare). Reproducible and GMP compliant fully automated production of [68Ga]Ga-ABY-025 was developed. The radiochemical purity of the product was 98.7 ± 0.6% with total peptide content of 315 ± 15 µg (n = 3). Radionuclidic purity, sterility, endotoxin content, residual solvent content, and sterile filter integrity were controlled and met acceptance criteria. The product was stable at ambient temperature for at least 2 h. The primary tumor and metastasis were detected with SUVmax values of 8.3 and 16.0, respectively. Automated production of [68Ga]Ga-ABY-025 was established and the process was validated enabling standardized multicenter phase II and III clinical trials and routine clinical use. Patient examinations conformed to the radiopharmaceutical biodistribution observed in the previous phase I study.
Molecular-Guided Surgery: Molecules, Devices, and Applications VII
European Journal of Nuclear Medicine and Molecular Imaging, 2010
European Journal of Nuclear Medicine and Molecular Imaging, 2014
Accuracy of [Ga-68]ABY-025 PET/CT for determination of HER2-expression in metastatic breast cancer
Journal of Clinical Oncology
Non-invasive determination of HER2-expression in metastatic breast cancer by using Ga-68-ABY025 P... more Non-invasive determination of HER2-expression in metastatic breast cancer by using Ga-68-ABY025 PET/CT.
EJNMMI Research
Background High expression of human epidermal growth factor receptor type 2 (HER2) represents an ... more Background High expression of human epidermal growth factor receptor type 2 (HER2) represents an aggressive subtype of breast cancer. Anti-HER2 treatment requires a theragnostic approach wherein sufficiently high receptor expression in biopsy material is mandatory. Heterogeneity and discordance of HER2 expression between primary tumour and metastases, as well as within a lesion, present a complication for the treatment and require multiple biopsies. Molecular imaging using the HER2-targeting Affibody peptide ABY-025 radiolabelled with 68Ga-gallium for PET/CT is currently under investigation as a non-invasive tool for whole-body evaluation of metastatic HER2 expression. Initial studies demonstrated a high correlation between 68Ga-ABY-025 standardized uptake values (SUVs) and histopathology. However, detecting small liver lesions might be compromised by high background uptake. This study aimed to explore the applicability of kinetic modelling and parametric image analysis for absolute...
Journal of Surgical Oncology
Fluorescence‐guided surgery using epidermal growth factor receptor (EGFR) targeting has been perf... more Fluorescence‐guided surgery using epidermal growth factor receptor (EGFR) targeting has been performed successfully in clinical trials using a variety of fluorescent agents. We investigate ABY‐029 (anti‐EGFR Affibody® molecule labeled with IRDye 800CW) compared with a small‐molecule perfusion agent, IRDye 700DX carboxylate, in a panel of soft‐tissue sarcomas with varying levels of EGFR expression and vascularization.
Cancer control : journal of the Moffitt Cancer Center
The excision of tumors by wide local excision is challenging because the mass must be removed ent... more The excision of tumors by wide local excision is challenging because the mass must be removed entirely without ever viewing it directly. Positive margin rates in sarcoma resection remain in the range of 20% to 35% and are associated with increased recurrence and decreased survival. Fluorescence-guided surgery (FGS) may improve surgical accuracy and has been utilized in other surgical specialties. ABY-029, an anti-epidermal growth factor receptor Affibody molecule covalently bound to the near-infrared fluorophore IRDye 800CW, is an excellent candidate for future FGS applications in sarcoma resection; however, conventional methods with direct surface tumor visualization are not immediately applicable. A novel technique involving imaging through a margin of normal tissue is needed. We review the past and present applications of FGS and present a novel concept of indirect FGS for visualizing tumor through a margin of normal tissue and aiding in excising the entire lesion as a single, co...
European Journal of Nuclear Medicine and Molecular Imaging, 2017
In phase I/II-studies radiolabelled ABY-025 Affibody molecules identified human epidermal growth ... more In phase I/II-studies radiolabelled ABY-025 Affibody molecules identified human epidermal growth factor receptor 2 (HER2) expression in breast cancer metastases using PET and SPECT imaging. Here, we wanted to investigate the utility of a simple intra-image normalization using tumour-to-reference tissue-ratio (T/R) as a HER2 status discrimination strategy to overcome potential issues related to cross-calibration of scanning devices. Methods Twenty-three women with pre-diagnosed HER2positive/negative metastasized breast cancer were scanned with [ 111 In]-ABY-025 SPECT/CT (n = 7) or [ 68 Ga]-ABY-025 PET/CT (n = 16). Uptake was measured in all metastases and in normal spleen, lung, liver, muscle, and blood pool. Normal tissue uptake variation and T/R-ratios were established for various time points and for two different doses of injected peptide from a total of 94 whole-body image acquisitions. Immunohistochemistry (IHC) was used to verify HER2 expression in 28 biopsied metastases. T/R-ratios were compared to IHC findings to establish the best reference tissue for each modality and each imaging time-point. The impact of shed HER2 in serum was investigated. Results Spleen was the best reference tissue across modalities, followed by blood pool and lung. Spleen-T/R was highly correlated to PET SUV in metastases after 2 h (r = 0.96, P < 0.001) and reached an accuracy of 100% for discriminating IHC HER2-positive and negative metastases at 4 h (PET) and 24 h (SPECT) after injection. In a single case, shed HER2 resulted in intense tracer retention in blood. In the remaining patients shed HER2 was elevated, but without significant impact on ABY-025 biodistribution. Conclusion T/R-ratios using spleen as reference tissue accurately quantify HER2 expression with radiolabelled ABY-025 imaging in breast cancer metastases with SPECT and PET. Tracer binding to shed HER2 in serum might affect quantification in the extreme case.
Molecular Imaging and Biology, 2016
ABY-029, a synthetic Affibody peptide, Z03115-Cys, labeled with a near-infrared fluorophore, IRDy... more ABY-029, a synthetic Affibody peptide, Z03115-Cys, labeled with a near-infrared fluorophore, IRDye® 800CW, targeting epidermal growth factor receptor (EGFR) has been produced under good manufacturing practices for a US Food and Drug Administration-approved first-in-use human study during surgical resection of glioma, as well as other tumors. Here, the pharmacology, phototoxicity, receptor activity, and biodistribution studies of ABY-029 were completed in rats, prior to the intended human use. Male and female Sprague Dawley rats were administered a single intravenous dose of varying concentrations (0, 245, 2449, and 24,490 μg/kg corresponding to 10×, 100×, and 1000× an equivalent human microdose level) of ABY-029 and observed for up to 14 days. Histopathological assessment of organs and tissues, clinical chemistry, and hematology were performed. In addition, pharmacokinetic clearance and biodistribution of ABY-029 were studied in subgroups of the animals. Phototoxicity and ABY-029 binding to human and rat EGFR were assessed in cell culture and on immobilized receptors, respectively. Histopathological assessment and hematological and clinical chemistry analysis demonstrated that single-dose ABY-029 produced no pathological evidence of toxicity at any dose level. No phototoxicity was observed in EGFR-positive and EGFR-negative glioma cell lines. Binding strength and pharmacokinetics of the anti-EGFR Affibody molecules were retained after labeling with the dye. Based on the successful safety profile of ABY-029, the 1000× human microdose 24.5 mg/kg was identified as the no observed adverse effect level following intravenous administration. Conserved binding strength and no observed light toxicity also demonstrated ABY-029 safety for human use.
Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 31, 2016
While extent of tumor resection is an important predictor of outcome in glioma, margin delineatio... more While extent of tumor resection is an important predictor of outcome in glioma, margin delineation remains challenging due to lack of inherent contrast between tumor and normal parenchyma. Fluorescence-guided surgery is promising for its ability to enhance contrast through exogenous fluorophores, however, the specificity and sensitivity of the underlying contrast mechanism and tumor delivery and uptake vary widely across approved and emerging agents. Rats with orthotopic F98 wild-type and F98 EGFR-positive gliomas received in vivo administration of IRDye680RD, 5-aminioleuvulinic acid, and ABY-029-markers of perfusion, protoporphyrin metabolism, and EGFR expression, respectively. Ex vivo imaging demonstrates the contrast mechanism-dependent spatial heterogeneity and enables within-animal comparisons of tumor-to-background ratio (TBR). Generally, ABY-029 outperformed PpIX in F98EGFR orthotopic tumor margins and core (50% and 60% higher TBR, respectively). PpIX outperformed ABY-029 in ...
Society of Nuclear Medicine Annual Meeting Abstracts, May 1, 2012