Targeting metabolic vulnerabilities in Astrocytoma, IDH-mutant, Grade 4

PROJECT SUMMARY
Gliomas represent 80% of the 26,000 newly diagnosed cases of malignant brain and central nervous system
tumors in the United States each year and are among the most lethal and treatment-resistant human cancers.
Although there is a dire need for effective therapies for this disease, the standard treatment for gliomas has not
changed since 2005 and no new medical therapies have been approved for adult gliomas in the last decade. In
response to this challenge, we have devised a new way to treat gliomas that have a mutation in either of the
IDH1 or IDH2 genes. Collectively, IDH mutations are present in ~20% of adult diffuse gliomas, indicating that
any treatment advance in this patient population would have broad impact. Based on our knowledge that IDH
mutations cause profound metabolic reprogramming in glioma cells, we used a novel pharmacological
screening platform to systematically identify vulnerabilities that result from this process. We discovered that a
class of drugs targeting nucleotide metabolism preferentially kill glioma cells with IDH mutations, thereby
revealing an avenue for tumor-selective, biomarker-guided therapy that is poised for rapid clinical translation.
To build on this discovery and translate exploitation of this vulnerability to the clinic, we propose to conduct a
phase 0 surgical window clinical trial of a brain-penetrant nucleotide metabolism inhibitor in IDH-mutant grade
4 glioma patients. We will characterize response to this agent by addressing three Specific Aims. Specific Aim
#1 is to use matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI), conventional
liquid chromatography-mass spectrometry, and magnetic resonance spectroscopy to comprehensively
characterize the pharmacokinetic and pharmacodynamic properties of this targeted therapeutic in glioma
patients. Specific Aim #2 is to investigate how this inhibitor alters the biology of IDH-mutant grade 4 gliomas at
the molecular and cellular levels by analyzing resected primary tissue samples via single-cell RNA sequencing
and immunohistochemistry. Finally, Specific Aim #3 is to evaluate the safety and tolerability of this drug in a
focused cohort of IDH-mutant grade 4 glioma patients. Taken together, our work will outline and test a new
treatment strategy for glioma patients that could be expanded to a larger multi-center phase II study if our trial
is successful. Furthermore, our efforts to elucidate key components of the mechanism of action of this
nucleotide metabolism inhibitor are expected to inform the rational design of combination therapies centered
on this agent that can be explored in future studies.

Grant Number: 5U19CA264504-05
NIH Institute/Center: NIH
Principal Investigator: Tracy Batchelor