OS05.9.A TUMOR DELINEATION IN MENINGIOMA WITH FG001, A NOVEL UPAR-TARGETING FLUORESCENT AGENT FOR OPTIMIZING SURGERY

Abstract BACKGROUND The principle of using a fluorescent agent for optimizing glioma surgery is well known. In surgery for meningioma this is less investigated. While FG001 (ICG-glu-glu-AE105), a uPAR-targeting peptide ligand, has proved high efficacy as a fluorescent aid in surgery for glioblastoma its ability to visualize pathological tissue in meningioma has so far only been demonstrated in a published case. Hence, the aim of our study is to investigate the capability of FG001 to demonstrate meaningful intraoperative visualization with both fluorescence in the tumor and a delineation towards the surrounding healthy dura to distinguish “dural tail” from reactive tissue in the meninges.. MATERIAL AND METHODS The trial is an open-label, non-randomized, single dose, phase II trial of FG001 for localization of meningiomas or presumed Low-Grade Gliomas scheduled for neurosurgery, here only results from meningioma are presented. The primary endpoint was to evaluate the sensitivity for detection of tumor tissue using histology as a reference. The fluorescent signal was judged as Tumor-to-Background Ratio (TBR). Kinevo 900 (Zeiss) with NIR imaging was used as surgical microscope. A total of 10 patients, mean age 59 (29-78y); 5 male and 5 female with a WHO grade 1 (6ptt) or WHO grade 2 (4 ptt) meningioma were included with FG001 administered with a mean time 23.5 h prior to surgery. RESULTS A positive fluorescence signal was detected in 9 of 10 patients on the dura and in all tumors with a high TBR (range 2.5-8.3). In the one patient with no fluorescence in the dura, the meningioma was attached to the falx and not the convexity, thus, the meninges were not invaded by meningioma cells. A total of 79 tissue samples from surgery (tumor and surrounding tissue) was scored double blinded by two neuropathologists. On a per-tissue-sample basis, we found an overall sensitivity of 97 % with 86 % specificity. On a per tumor basis, the sensitivity was 100%. Post-surgical imaging with MR showed complete removal of the tumor in all cases. CONCLUSION FG001 demonstrated a high sensitivity for detection of not only tumor but also invasion into meningeal tissue known as dural tail. The potential benefit using FG001 in surgery for meningioma is to tailor the removal of tumor and only the part of meninges with a true invasion of meningeal cells hindering recurrence to the largest possible extent while keeping the adverse events of healthy dura removal to a minimum. DISCLOSURE This study is an investigator initiated study performed in the Neurosurgical Department, Rigshospitalet, Copenhagen. Study grant includes: Life Science Innovation North Denmark; Læge Sofus Carl Emil Friis og Hustru Olga Doris Friis Legat; FluoGuide delievered the study drug free of charges in return for Safety Data with no further sponsoring of the study. KS is an employee at, and AK is a co-founder of FluoGuide.