Low Grade Glioma Patients and Vorasidenib: A Potential Treatment

AIMS Low-grade gliomas (LGG) are characterised by: complex pathology, diverse clinical behaviour and challenging surgical and oncological management. NICE currently recommends for patients >40 years old: surgery, ra- diotherapy and adjuvant PCV chemotherapy for residual LGG disease. The INDIGO trial investigated the role of Vorasidenib, an IDH-mutant inhibitor, in LGG and showed significant improvement in progression-free survival (PFS) and time to intervention. Our aim was to determine the number of LGG patients eligible for Vorasidenib. METHODS A retrospective review of all LGG patients at The Walton Centre Hospital was performed using the: Neuro- oncology database, clinical records and pathology datasets. Only patients >16 years of age, diagnosed with WHO Grade II LGG: astrocytoma or oligodendroglioma as per the WHO Classification 2021, were included in the study. Data was collected from 2018 onwards to ensure treatment within the last 5-years. The inclusion and exclusion criteria were followed as per the INDIGO trial for eligibility: Karnofsky Perfor- mance Score >70, at least one previous surgery, no anti-cancer treatment and measurable non-enhancing dis- ease >1cm. RESULTS In total, 111 LGG patients were treated within the last 5-years. Of these, 24 patients were excluded due to re- location or progression of disease, leaving 87 patients. Male to female ratio was 55:45 with a median age of 39. The most common location was frontal (63%). Overall, 16% (14/87) of patients were eligible for Vorasidenib, with the main excluding factor being prior anti-cancer treatment. CONCLUSION At present, Vorasidenib is not available in the UK and is awaiting approval by the MHRA and subsequent cost- effectiveness review by NICE. If INDIGO is followed, a significant number of patients will be excluded. However, we aim to start treating patients eligible once the IDH dual inhibitor is available to use in the NHS in order to optimise care for our patients.