Temozolomide

證據等級: L5

預測適應症: 2 個

Temozolomide: From Glioblastoma to Adult Astrocytic Tumour

One-Sentence Summary

Temozolomide is an oral alkylating agent whose established use, as documented in the underlying trial and literature evidence, is newly diagnosed glioblastoma — the most common and aggressive primary brain tumour in adults. The TxGNN model predicts it may also be effective across the broader Adult Astrocytic Tumour category, a prediction already supported by 2 clinical trials and 20 publications, including the landmark Stupp-regimen randomized trial that underlies current glioma standard of care.

Quick Overview

Item	Content
Original Indication	Glioblastoma / malignant glioma (per evidence literature; no New Zealand license text available since the drug is not currently marketed there)
Predicted New Indication	Adult Astrocytic Tumour
TxGNN Prediction Score	99.36%
Evidence Level	L1
New Zealand Market Status	✗ Not marketed
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism-of-action data is not available in structured form. Based on information within the supporting literature, temozolomide is a second-generation imidazotetrazine alkylating agent that is administered orally and exerts a DNA-damaging (alkylating) effect on rapidly dividing tumour cells.

The relationship between the original and predicted indications is very close rather than distant: glioblastoma is itself classified as a grade IV astrocytic tumour, and anaplastic astrocytoma (grade III) is part of the same tumour family. The "Adult Astrocytic Tumour" prediction therefore largely reflects an extension of temozolomide's already-established efficacy across the full astrocytic tumour spectrum (e.g., recurrent WHO grade III/IV astrocytoma), rather than a mechanistically novel application.

Mechanistically, the alkylating/DNA-damaging activity of temozolomide is not specific to one histologic grade — it targets proliferating glial-lineage tumour cells broadly, which is consistent with activity across astrocytic tumours of varying grade, as reflected in the randomized trial evidence below (e.g., the NOA-08 and CeTeG/NOA-09 trials in anaplastic astrocytoma/glioblastoma populations).

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT00052455	Phase 3	Completed	500	Randomized trial comparing temozolomide alone vs. PCV (procarbazine, lomustine, vincristine) in recurrent WHO grade III/IV astrocytic tumours
NCT00960492	Phase 1	Completed	26	Dose-finding study of XL184 combined with temozolomide and radiotherapy in first-line glioblastoma

Literature Evidence

PMID	Year	Type	Journal	Key Findings
15758009	2005	RCT	N Engl J Med	Landmark EORTC-NCIC trial: radiotherapy plus concomitant/adjuvant temozolomide vs. radiotherapy alone in newly diagnosed glioblastoma
19269895	2009	RCT (5-yr follow-up)	Lancet Oncol	5-year survival analysis confirming durable benefit of temozolomide + radiotherapy in glioblastoma
26670971	2015	RCT	JAMA	Tumor-Treating Fields plus temozolomide vs. temozolomide alone as maintenance therapy for glioblastoma
30782343	2019	RCT	Lancet	CeTeG/NOA-09: lomustine-temozolomide vs. standard temozolomide in MGMT-methylated glioblastoma
22578793	2012	RCT	Lancet Oncol	NOA-08: temozolomide alone vs. radiotherapy alone in elderly malignant astrocytoma
24552317	2014	RCT	N Engl J Med	Randomized trial of bevacizumab added to standard temozolomide/radiotherapy in newly diagnosed glioblastoma
40779733	2025	RCT (Phase II/III)	J Clin Oncol	NRG Oncology BN007: dual immune checkpoint blockade in MGMT-unmethylated newly diagnosed glioblastoma
36809318	2023	Review	JAMA	Overview of glioblastoma and other primary adult brain malignancies, including temozolomide-based standard of care
29075865	2017	Review	Curr Oncol Rep	Review of glioblastoma treatment approaches in older adults
25920709	2015	Clinical trial report	J Neurooncol	Exploratory cohort of concurrent radiotherapy and temozolomide in anaplastic astrocytic gliomas

New Zealand Market Information

Temozolomide currently holds no product authorizations in New Zealand (market status: 未上市 / not marketed; total licenses: 0).

Cytotoxicity

Item	Content
Cytotoxicity Classification	Conventional cytotoxic (alkylating agent, imidazotetrazine class)
Myelosuppression Risk	Please refer to the package insert warnings and precautions
Emetogenicity Classification	Please refer to the package insert warnings and precautions
Monitoring Items	Please refer to the package insert warnings and precautions
Handling Protection	Cytotoxic drug handling precautions are expected given the alkylating-agent classification; specific institutional protocol requirements should follow package insert guidance

Safety Considerations

Please refer to the package insert for safety information.

Conclusion and Next Steps

Decision: Hold

Rationale: Efficacy evidence for the astrocytic tumour indication is strong (L1, multiple completed Phase 3 RCTs), but a Blocking data gap exists — TFDA/NZ package insert warnings and contraindications are unavailable, which prevents even a preliminary (S1) safety assessment. The drug also has no current market authorization in New Zealand.

To proceed, the following is needed:

Official package insert / label safety data (warnings, contraindications) from a regulatory source
Confirmed mechanism-of-action documentation (e.g., via DrugBank API)
Drug-drug interaction data (current DDI query returned no results)
Assessment of route/formulation availability for potential New Zealand market entry
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.