Testing the Addition of an Anti-Cancer Drug, Triapine, to the Usual Radiation Therapy for Recurrent Glioblastoma or Astrocytoma

Phase 1

Not yet recruiting

• Conditions: Astrocytoma, IDH-Mutant, Grade 2; Recurrent Astrocytoma, IDH-Mutant; Recurrent Astrocytoma, IDH-Mutant, Grade 3; Recurrent Astrocytoma, IDH-Mutant, Grade 4; Recurrent Diffuse Midline Glioma; Recurrent Glioblastoma, IDH-Wildtype
• Interventions: Procedure: Biospecimen Collection; Procedure: Computed Tomography; Radiation: Intensity-Modulated Radiation Therapy; Procedure: Magnetic Resonance Imaging; Drug: Triapine

• Registration Number: NCT06860594
• Lead Sponsor: National Cancer Institute (NCI)

Brief Summary

This phase I trial tests the safety, side effects, and best dose of triapine in combination with radiation therapy in treating patients with glioblastoma or astrocytoma that has come back after a period of improvement (recurrent). Triapine may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Radiation therapy uses high energy x-rays, particles, or radioactive seeds to kill cancer cells and shrink tumors. Giving triapine in combination with radiation therapy may be safe, tolerable, and/or effective in treating patients with recurrent glioblastoma or astrocytoma.

Detailed Description

PRIMARY OBJECTIVE:

I. To identify the safety and maximally tolerated dose (MTD) of oral triapine used in combination with radiation therapy for patients with recurrent glioblastoma (GBM) or astrocytoma.

SECONDARY OBJECTIVES:

I. To observe and record anti-tumor activity. II. To determine the pharmacokinetics of oral triapine in plasma and the central nervous system (CNS).

III. To evaluate the efficacy of triapine when administered in combination with radiation therapy by assessing:

IIIa. Progression-free survival (PFS); IIIb. Overall survival (OS); IIIc. The proportion of patients requiring bevacizumab for symptom control; IIId. The correlation of genetic mutations in select genes (e.g., p53, p16, KRAS, and Pi3k/mTOR/AKT) with tumor response and clinical outcomes.

OUTLINE: This is a dose-escalation study of triapine in combination with radiation therapy.

Patients undergo intensity-modulated radiation therapy (IMRT) once daily (QD) 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine orally (PO) 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo computed tomography (CT) and/or magnetic resonance imaging (MRI) throughout the study as well as blood sample collection during screening and on study. Patients may undergo cerebrospinal fluid (CSF) sample collection during screening.

After completion of study treatment, patients are followed up at 2 weeks after radiation therapy, then every 3 months for up to 2 years.

Study Timeline

• Study First Submitted: 2025-03-05
• Study First Submitted QC: 2025-03-05
• Study First Posted: 2025-03-06
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-08
• Last Update Posted: 2025-04-09
• Study Start: 2025-06-04
• Primary Completion: 2027-06-01
• Study Completion: 2027-06-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Patients must have histologically, molecularly, or cytologically confirmed recurrent astrocytic tumors including:

  • GBM or variants, IDH-wildtype, grade 2-4 (standard curative measures available or not)
  • Astrocytoma, IDH-mutant, grade 2-4 (standard curative measures available or not)
  • Diffuse midline gliomas, including pediatric-type H3K G34 or E3 K27 mutant tumors.

• Tumors ≤ 6 cm in maximal diameter.

• Patients must have at least a 6-month break from last dose of radiation therapy.

Re-irradiation within 6 months may increase risk for radiation necrosis/edema, which will affect toxicity assessment and patient safety. Additionally, GBM and other high-grade astrocytic tumors can exhibit pseudo-progression within 6 months from completing definitive, 1st line radiation therapy, and re-irradiation during this period will increase risk for misattribution of effect.

• Prior history of standard dose radiation for gliomas of 59.4-60 gray (Gy) in 1.8-2 Gy per fraction (or equivalent or lower) is allowed.

• Patients who received non-standard radiation such as stereotactic radiosurgery are eligible as long as there is:

  • A new tumor outside the original radiotherapy field as determined by the investigator.
  • There is histologic confirmation of tumor on biopsy or resection.
  • Imaging findings on MRI spectroscopy/perfusion imaging/nuclear medicine imaging are consistent with true progressive disease.

• Age ≥ 18 years. Because no dosing or adverse event data are currently available on the use of triapine in patients < 18 years of age, children are excluded from this study.

• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 (Karnofsky ≥ 60%).

• Absolute neutrophil count ≥ 1,500/mcL.

• Hemoglobin ≥ 8 g/dL.

• Platelets ≥ 100,000/mcL.

• Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN).

• Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase [SGOT])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) ≤ 3 x institutional ULN.

• Creatinine ≤ 1.5 x ULN OR glomerular filtration rate (GFR) ≥ 50 mL/min/1.73 m^2.

• Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial.

• For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated.

• Patients with a history of hepatitis C virus (HCV) infection must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load.

• Patients with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial.

• Patients with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, should have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification. To be eligible for this trial, patients should be class II or better.

• Patients must be able to swallow whole capsules.

• Patients must be able to undergo MRIs. Patients with non-compatible devices with MRI can be eligible if CT scans of sufficient quality are obtained. However, patients without non-compatible devices may not use CT scans to meet this requirement.

• The effects of triapine on the developing human fetus are unknown. For this reason and because ribonucleotide reductase (RNR) inhibitor agent and radiation are known to be teratogenic, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study participation, and for 12 months after finishing study treatment. People of child-bearing potential must have a negative serum or urine pregnancy test (minimum sensitivity 25 IU/L or equivalent units of human chorionic gonadotropin [HCG]) within 2 weeks of registration. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. Men treated or enrolled on this protocol must also agree to use adequate contraception prior to the study, for the duration of study participation, and 12 months after completion of triapine administration.

• Ability to understand and the willingness to sign a written informed consent document. Legally authorized representatives may sign and give informed consent on behalf of study participants.

Exclusion Criteria

• Patients who have not recovered from adverse events due to prior anti-cancer therapy (i.e., have residual toxicities > grade 1) with the exception of alopecia.
• Patients who are receiving any other investigational agents.
• Patients who are actively taking medications that are known to induce methemoglobinemia (e.g. sulfonamides, nitrofurans, anti-malarials [primaquine, chloroquine], cyclophophsamide, and ifosfamide).
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to triapine.
• Patients with known G6PD deficiency. Testing for G6PD deficiency is not required.
• Patients with uncontrolled intercurrent illness, active infections, or any other significant condition(s) that would make participation in this protocol unreasonably hazardous.
• Pregnant women are excluded from this study because triapine is a RNR inhibitor agent with the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with triapine, breastfeeding should be discontinued if the mother is treated with triapine. These potential risks may also apply to the radiation used in this study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Treatment (IMRT, triapine)	Biospecimen Collection	Patients undergo IMRT QD 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine PO 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo CT and/or MRI throughout the study as well as blood sample collection during screening and on study. Patients may undergo CSF sample collection during screening.
Treatment (IMRT, triapine)	Computed Tomography	Patients undergo IMRT QD 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine PO 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo CT and/or MRI throughout the study as well as blood sample collection during screening and on study. Patients may undergo CSF sample collection during screening.
Treatment (IMRT, triapine)	Intensity-Modulated Radiation Therapy	Patients undergo IMRT QD 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine PO 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo CT and/or MRI throughout the study as well as blood sample collection during screening and on study. Patients may undergo CSF sample collection during screening.
Treatment (IMRT, triapine)	Magnetic Resonance Imaging	Patients undergo IMRT QD 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine PO 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo CT and/or MRI throughout the study as well as blood sample collection during screening and on study. Patients may undergo CSF sample collection during screening.
Treatment (IMRT, triapine)	Triapine	Patients undergo IMRT QD 5 days per week (Monday-Friday) for a total of 10 treatment days over 2 weeks and receive triapine PO 2 hours prior to IMRT on each radiation treatment day in the absence of disease progression or unacceptable toxicity. Patients also undergo CT and/or MRI throughout the study as well as blood sample collection during screening and on study. Patients may undergo CSF sample collection during screening.

Primary Outcome Measures

Name	Time	Method
Incidence of dose-limiting toxicity	Up to 28 days	Will be graded in severity according to the Common Terminology Criteria for Adverse Events version 5.0. Frequency and severity of adverse events and tolerability of the regimen will be collected and summarized with descriptive statistics. The maximum grade for each type of toxicity will be recorded for each patient and frequency tables will be reviewed to determine toxicity patterns. Will employ the Backfill Bayesian Optimal Interval design to guide dose escalation and establish the maximal tolerated dose (MTD). The target toxicity rate for the MTD is = 0.25.

Secondary Outcome Measures

Name	Time	Method
Response rate	Up to 2 years	Response rate will be categorized based on the Response Assessment in Neuro-Oncology criteria, in which tumor response is based on clinical history, physical exam, and imaging findings. The total number of patients in each response category divided by the total number of evaluable patients determines response rate. An evaluable patient is defined as an eligible patient who received at least one dose of triapine. The response rates will be calculated with corresponding 95% exact Clopper-Pearson confidence intervals.
Plasma pharmacokinetic (PK) parameters	Up to 2 weeks	Triapine in plasma and peri-tumoral dialysate will be quantified using a validated liquid chromatography-tandem mass spectrometry assay. Plasma PK parameters will be derived and compared to historical controls. Dialysate concentrations will be calculated at multiple time points. Exploratorily, exposure-response relationships will be evaluated.
Overall survival	From study enrollment to date of death, assessed up to 2 years	Will be estimated using Kaplan Meier curves.
Proportion of patients who initiated bevacizumab for symptom control	Up to 2 years	Will be calculated using descriptive statistics.
Progression-free survival	From study enrollment to date of either disease progression or death, assessed up to 2 years	Will be estimated using Kaplan Meier curves.
Tumor tissue biomarkers	Up to 2 years	The presence of genetic alterations, expression of RRM2, and other molecular gene expression signatures will be descriptive in relation to tumor response and clinical outcomes.