Novel Urokinase-Type Plasminogen Activator Receptor-Targeting Optical Imaging Agent ICG-Glu-Glu-AE105 for Visualization of Malignant Glioma During Surgery: First-in-Human Study in 35 Patients with Brain Cancer

BACKGROUND AND OBJECTIVES: Glioblastoma is an aggressive form of brain cancer for which surgery is the keystone in treatment before oncological treatment. Improving surgical resection without jeopardizing the outcome is eminent, and a fluorescent drug to aid surgical outcome is warranted. To evaluate the safety and the efficacy of a novel urokinase-type Plasminogen Activator Receptor-targeting near-infrared optical imaging agent, ICG-Glu-Glu-AE105 (FG001), in patients with malignant glioma (glioblastoma).

METHODS: First-in-human phase I dose escalation and time elaboration study in 35 patients undergoing surgery for glioblastoma. The tumor-to-background ratio (TBR) was measured on near-infrared images as an objective measure of image contrast. Biopsies were taken during surgery from areas with and without fluorescence (FG001) and compared with pathology as reference. Efficacy was evaluated as sensitivity and specificity of FG001 to detect tumor tissue. The study was conducted with close safety monitoring.

RESULTS: Administration of FG001 at a dose of 36 mg, 12 to 17 hours before surgery, resulted in optimal image contrast between tumor and normal brain tissue, with a mean TBR of 3.6. A high sensitivity (79%) and specificity (100%) for the detection of tumor tissue was found. Safety monitoring during the study identified only a few related adverse events, all of which were of mild grade.

CONCLUSION: FG001 was found to be safe and well tolerated in the patients included in the study. The optimal dose of FG001 was selected on the basis of videos taken during the surgery and the measured TBR values. A dose of 36 mg administered 16 hours (mean) before the surgery showed the best contrast (TBR values) and optimal visualization of the tumor delineation. Histology demonstrated good sensitivity of FG001.