# Phase II Clinical Trial of G207 HSV To Treat Children with High Grade Gliomas

> **NIH NIH R44** · TREOVIR, INC · 2023 · $890,765

## Abstract

Treovir, LLC is requesting Small Business Innovation Research (SBIR) support to conduct a single arm Phase II
clinical trial in children (age 3-18 years) who have been diagnosed with recurrent or progressive high grade
glioma (HGG). We propose to determine efficacy of a cGMP-produced (clinical grade) G207 Herpes Simplex
Virus (HSV) in children with recurrent HGG. Our rationale is based on a Phase I clinical trial of G207 in children
with recurrent HGG that has (1) established safety of intratumoral infusion of G207 HSV, alone or with a 5Gy
fraction of radiotherapy and (2) resulted in an apparent significant increase in overall survival. We have orphan
drug designations for G207 HSV for treatment of HGG (glioblastoma multiforme, Ependymomas),
Medulloblastoma, and Primitive Neuroectodermal Tumors (PNETs). G207 has been used safely in 3 clinical
trials in 35 adults with recurrent HGG with 17 obvious radiographic responses and at least 2 long term survivors
(>5.5 years) in a patient population with an expected median survival of 5.5–6.5 months. We have published
compelling preclinical data using in vitro cultures and mouse models of pediatric brain tumors that demonstrated
an increased sensitivity to G207 compared with adult brain tumors. In children with HGG, we have observed
radiographic, neuropathologic and/or clinical responses in 9 of 10 patients and a median survival of 12.2 months
(95% CI=5.05–19.4) with 3 patients surviving long-term (18.3, 20+ and 32+ months). A recent meta-analysis
(Kline et al., 2018) reported an average median survival of 5.6 months (95% CI=3.9-7.3) for 129 children with
recurrent HGG in 17 clinical trials. G207 is not just producing an oncolytic effect but is obviously eliciting a potent
immune inflammatory cell-based response. Immunohistochemical examination of 4 paired samples (pre- vs.
post-virus tumor) revealed extensive infiltration of immune-related inflammatory cells in all 4 post-treatment
tumor even 5 months post-G207. We propose that G207 infection of tumor cells converts an immunologically
“cold” tumor to a “hot” one. We propose to conduct a Phase II trial to determine efficacy of a single intratumoral
G207 infusion plus a single 5Gy fraction of radiation. The lead institution will be Children's of Alabama, University
of Alabama at Birmingham together with other Pediatric Hospitals with experience in immunotherapy/virotherapy
for brain tumors. This Phase II trial will involve a total of 32 subjects accrued according to the same
inclusion/exclusion criteria as in the current Phase I trial (NCT02457845). The Recommended Phase II Dose
(RP2D) will be 1 x 108 plaque-forming units (pfu) infused into multiple sites of the enhancing portions of the brain
tumor in a total volume of 2.4cc. The overall clinical PI will be Gregory K. Friedman, MD, who has conducted the
Phase I trial with G207 provided by Treovir, LLC. We hypothesize that 38 (both Phase I and II) subjects will
provide >85% power to detect a significant dif...

## Key facts

- **NIH application ID:** 10244948
- **Project number:** 5R44CA250883-03
- **Recipient organization:** TREOVIR, INC
- **Principal Investigator:** George Yancey Gillespie
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2023
- **Award amount:** $890,765
- **Award type:** 5
- **Project period:** 2020-09-01 → 2025-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10244948

## Citation

> US National Institutes of Health, RePORTER application 10244948, Phase II Clinical Trial of G207 HSV To Treat Children with High Grade Gliomas (5R44CA250883-03). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10244948. Licensed CC0.

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