Issues to Consider in Designing Immunotherapy Clinical Trials for Glioblastoma Management

Abstract

Glioblastoma (GBM) is the most common primary brain malignancy in adults and has a poor prognosis despite standard of care treatment. The mainstay of GBM treatment has relied on maximum surgical resection and chemotherapy and radiation. Cancer immunotherapy has made great strides since the advent of anti-PD-1, anti-CTLA-4, and other immune checkpoint inhibitors. With the advancement of novel therapeutics, more clinical trials for patients have opened as well. An important future direction of clinical trials is the ability to identify appropriate patients to optimize treatment response and minimize toxicities. This review describes considerations in designing future GBM clinical trials in not only immunotherapy but also with other promising treatments. We will discuss factors, such as pseudoprogression, genetic and circulating biomarkers, and the commensal microbiome of patients in the setting of clinical trial design.