Glioblastoma Clinical Trials: Current Landscape and Opportunities for Improvement

Abstract

Therapeutic advances for glioblastoma have been minimal over the past 2 decades. In light of the multitude of recent phase III trials that have failed to meet their primary endpoints following promising preclinical and early-phase programs, a Society for Neuro-Oncology Think Tank was held in November 2020 to prioritize areas for improvement in the conduct of glioblastoma clinical trials. Here, we review the literature, identify challenges related to clinical trial eligibility criteria and trial design in glioblastoma, and provide recommendations from the Think Tank. In addition, we provide a data-driven context with which to frame this discussion by analyzing key study design features of adult glioblastoma clinical trials listed on ClinicalTrials.gov as "recruiting" or "not yet recruiting" as of February 2021.

Figure 1.

Type of systemic therapy administered in glioblastoma clinical trials that include a systemic therapy component (n = 136).

Figure 2.

Key eligibility criteria in current glioblastoma clinical trials. A, Required minimum performance status (all trials; N = 157). B, Number of prior relapses permitted (recurrent glioblastoma trials; n = 93). C, Allowance for prior bevacizumab (recurrent glioblastoma trials; n = 93). D, Allowance of TTFields (newly diagnosed glioblastoma trials; n = 73).