Assessment of the clinical effectiveness and safety of immune checkpoint inhibitors for glioblastoma: A systematic review

Abstract

Glioblastoma (GBM) is a malignant primary brain tumor which is commonly found in humans. Conventional therapeutic approaches for GBM offer only a short median overall survival (MOS), thereby accentuating its poor clinical outcome. Despite the promising potential shown by use of immune checkpoint inhibitor (ICI) in animal models to treat GBM, human trials result remains inconclusive. This systematic review evaluated the safety and clinical efficacy of ICIs in GBM patients. A literature search from Embase and MEDLINE (Ovid) was completed in October 2023. A total of 10 suitable articles, which encompass 168 patients (164 recurrent and 4 newly-diagnosed GBM), are taken into account. 3 studies assessed the OS, 7 studies assessed the PFS and/or response assessment in neuro-oncology (RANO) criteria and 8 studies assessed the safety, tolerability and/or adverse events. These studies show that the range of MOS of ICI treatments was between 2.6-10.4 months (MOS using current standard treatment for recurrent GBM = 3.5-12.5 months). The median PFS and the median period until patients reach partial response score based on RANO criteria are ranging from 1.5 months to 4.6 months (PFS using current standard treatment is 5.5 months). In conclusion, ICIs are safe in patients with GBM. Reported adverse effects only include mild fatigue, headache, hyperglycemia, and diarrhea. However, ICIs display suboptimal clinical efficacy compared to conventional GBM treatments. Therefore, further research is needed in order to improve the clinical efficacy of ICIs.