Health Technology Assessment on Gleolan for High-Grade Gliomas

Condition Description – High-grade gliomas are aggressive and life-threatening tumors that arise from glial cells in the brain or spinal cord. Symptoms significantly affect quality of life and may include headaches, seizures, cognitive changes, behavioral changes, and motor deficits. The median survival rate for the most severe high-grade gliomas is approximately 15 months, with a 5-year survival rate of 5-10% for grade IV gliomas. The incidence of high-grade gliomas is rare, affecting approximately 3-5 individuals per 100,000 and occurring more frequently in men than women.

Current treatment options – Standard treatment for high-grade gliomas includes surgery, radiation therapy, and chemotherapy, used alone or in combination. Conventional surgical resection utilizes intraoperative imaging technologies, such as a standard operating microscope under white light. The primary goals of surgery are to obtain a tissue diagnosis, relieve intracranial pressure, and maximize tumour resection while preserving critical brain function. However, complete tumour resection is challenging due to the difficulty in distinguishing tumour tissue from healthy brain tissue.

Description of the Assessed Technology(ies) - Gleolan (5-aminolevulinic acid), also known as Gliolan, is an orally administered dye given 2-4 hours before anesthesia. It enables the visualization of tumour cells by causing them to fluoresce, thereby assisting surgeons in differentiating malignant tumour tissue from normal brain tissue. This improved visualization aims to facilitate maximal safe resection of high-grade gliomas.

Health Technology Assessment Committee’s Findings: 

After review of the HTA, the Health Technology Assessment Committee found that Gleolan is at least as clinically effective compared to standard surgical resection using a white-light operating microscope, with the following key findings:

• Limited evidence suggests improved overall survival outcomes, including higher survival rates, longer median survival, and lower hazard ratio of mortality when Gleolan is used in surgery.

• The risks of Gleolan are considered low.

• The quality of available evidence is limited with a high potential for bias.

While the cost of Gleolan is low compared to the treatment costs for this patient population and the evidence suggests improved patient outcomes, the evidence is limited and potentially biased. It will be at the discretion of each health authority to assess the value of potential benefits in comparison to the additional implementation cost of Gleolan.