Gleolan for Visualization of Newly Diagnosed or Recurrent Meningioma

This Phase 3 open-label single-arm study is designed to investigate the safety, diagnostic performance, and clinical usefulness of the imaging agent Gleolan™ (Aminolevulinic Acid Hydrochloride, ALA HCl, ALA, 5-ALA), an orally administered imaging agent for the real time detection and visualization of meningiomas during tumor resection surgery. ALA is a prodrug that is metabolized intracellularly to form the fluorescent molecule Protoporphyrin IX (PpIX). The exogenous application of ALA leads to a highly selective accumulation of PpIX in tumor cells. Following excitation with blue light (BL) (λ = 375 - 440 nm), the PpIX, which has accumulated selectively in tumor tissue, emits a red-violet light. This phenomenon allows for the real-time visualization of tumor tissue during resection surgery. Patients about to undergo resection for suspected meningioma \[World Health Organization (WHO) Grade I, II, III\] will be screened and informed consent will be obtained prior to surgery and prior to study participation. Eligible study participants will receive an oral solution of Gleolan (20 mg/kg body weight) 3 hours, (target range 2-4 hours) prior to anesthesia, and then undergo surgery for meningioma resection. During the surgery, the surgeon will use a microscope equipped with WL and BL for visualization of Gleolan-induced PpIX fluorescence for the selection of protocol-driven tissue locations and to assess fluorescence status. Study participants will be evaluated within 48 hours post procedure, 2 weeks post procedure, and 6 weeks post procedure for study safety assessment.