Thiotepa
| Evidence Level: L2 | Predicted Indications: 10 |
Table of Contents
Thiotepa: From High-Dose Conditioning Chemotherapy to Adult Germ Cell Tumor
One-Sentence Summary
Thiotepa is an alkylating agent long used as part of high-dose conditioning chemotherapy regimens before autologous stem cell transplantation, though no formal original indication or EU marketing authorization is recorded in this Evidence Pack. The TxGNN model predicts it may be effective for Adult Germ Cell Tumor, a use already reflected in real-world clinical practice, with 17 clinical trials and 19 publications currently supporting this direction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not formally registered in this Evidence Pack; clinical trial data show thiotepa is established as an off-label component of high-dose conditioning chemotherapy prior to autologous stem cell transplantation |
| Predicted New Indication | Adult Germ Cell Tumor |
| TxGNN Prediction Score | 98.51% |
| Evidence Level | L2 |
| EU Market Status | Not Marketed |
| Number of Authorizations | 0 |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data for thiotepa is not available in this Evidence Pack (flagged as a High-severity data gap). Based on the information that is available, thiotepa is an alkylating agent that inhibits tumour cell replication via DNA cross-linking. It is a core component of high-dose chemotherapy (HDCT) conditioning regimens used before autologous stem cell transplantation (ASCT), typically combined with agents such as carboplatin and etoposide (e.g., the TVCa or BET regimens).
Germ cell tumours are highly chemosensitive, and salvage HDCT with ASCT is an established treatment strategy for relapsed or refractory disease. The clinical trial and literature evidence collected here show that thiotepa-based regimens have already been used in real-world practice for germ cell tumours, including both testicular/ovarian and central nervous system (CNS) germ cell tumours, following relapse after conventional platinum-based chemotherapy. This means the TxGNN prediction is not proposing an entirely novel mechanism, but rather reinforces and consolidates existing off-label clinical experience into a structured indication signal.
Because the original indication and formal MOA are not documented in this pack, the mechanistic rationale above relies on the model’s own supporting evidence (clinical trials and literature) rather than an approved label reference.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00432094 | Phase 2 | Completed | 23 | Autologous peripheral blood stem cell transplant specifically for germ cell tumours; high-dose chemotherapy as salvage therapy for poor-risk/relapsed disease |
| NCT04684368 | Phase 2 | Recruiting | 160 | Chemotherapy followed by response-based whole ventricular & spinal canal irradiation for localized non-germinomatous CNS germ cell tumours |
| NCT00025324 | Phase 2 | Unknown | N/A | Third International CNS Germ Cell Tumor Study Group protocol combining chemotherapy, surgery, radiotherapy and stem cell transplantation |
| NCT00536601 | NA | Completed | 174 | High-dose chemotherapy regimens with/without TBI before autologous stem cell transplant across hematologic and solid tumours |
| NCT00060255 | Phase 2 | Completed | 451 | Eight high-dose chemotherapy regimens combined with autologous BMT/stem cell transplant for hematologic malignancies and selected solid tumours |
| NCT00007982 | Phase 2 | Completed | 30 | CAMP004A BET (thiotepa-containing) intensive chemotherapy regimen for selected malignant CNS tumours |
| NCT00003173 | Phase 2 | Completed | 36 | High-dose thiotepa plus autologous stem cell rescue in patients with refractory solid tumours |
| NCT00008008 | Phase 2 | Completed | 40 | Tandem thiotepa regimen (CAMP013) for malignant gliomas refractory to standard chemotherapy |
| NCT00003081 | Phase 1 | Completed | 16 | Busulfan, thiotepa and melphalan followed by autologous/syngeneic PBSCT and total marrow irradiation in high-risk Ewing’s sarcoma, PNET or rhabdomyosarcoma |
| NCT00336024 | Phase 3 | Completed | 91 | Randomized comparison of methotrexate-containing vs non-containing induction chemotherapy followed by stem cell rescue in young children with PNET/high-risk medulloblastoma |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 31454045 | 2019 | RCT | JAMA | Tandem vs single autologous stem cell transplant improves event-free survival in high-risk neuroblastoma, supporting the transplant-conditioning role of alkylating agents such as thiotepa |
| 11801470 | 2002 | Review | Haematologica | Reviews the status of high-dose chemotherapy with hematopoietic stem cell transplantation as salvage or first-line therapy in poor-prognosis germ cell tumour patients |
| 28463397 | 2017 | Cohort | International Journal of Cancer | Large UK/German cohort of relapsed intracranial germ cell tumours; assesses value of HDCT plus autologous stem cell rescue and re-irradiation |
| 16503505 | 2006 | Cohort | Biology of Blood and Marrow Transplantation | 64 patients with high-, intermediate- and low-risk germ cell tumours treated with intensive chemotherapy and autologous PBSCT over 10 years |
| 15143087 | 2004 | Cohort | Journal of Clinical Oncology | Thiotepa-based high-dose chemotherapy with autologous stem-cell rescue in patients with recurrent/progressive CNS germ cell tumours |
| 23824533 | 2013 | Cohort | Journal of Neuro-Oncology | Korean Society of Pediatric Neuro-Oncology (KSPNO) study of myeloablative chemotherapy and autologous stem cell transplantation in relapsed/progressed CNS germ cell tumours |
| 15803005 | 2005 | Cohort | American Journal of Clinical Oncology | High-dose etoposide, thiotepa and dose-adjusted carboplatin (TVCa) with autologous hematopoietic stem cell rescue for relapsed/refractory germ cell cancer |
| 28905508 | 2018 | Cohort | Pediatric Blood & Cancer | Feasibility and tolerability of tandem high-dose thiotepa with autologous hematopoietic cell rescue in recurrent/refractory solid tumours |
| 9440746 | 1998 | Cohort | Journal of Clinical Oncology | High-dose carboplatin, thiotepa and etoposide with autologous stem-cell rescue for recurrent medulloblastoma (Children’s Cancer Group) |
| 20167818 | 2010 | Cohort | Neuro-Oncology | High-dose carboplatin, thiotepa and etoposide with autologous stem cell rescue in previously irradiated recurrent medulloblastoma |
EU Market Information
No EU marketing authorizations are currently registered for this product in the Evidence Pack (market status: Not Marketed; total authorizations: 0).
Cytotoxicity
| Item | Content |
|---|---|
| Cytotoxicity Classification | Conventional cytotoxic (alkylating agent) |
| Myelosuppression Risk | High — the collected trial evidence consistently uses thiotepa at myeloablative, high-dose levels requiring autologous stem cell rescue, indicating substantial bone marrow suppression |
| Emetogenicity Classification | Please refer to the SmPC warnings and precautions |
| Monitoring Items | Complete blood count (CBC) with differential; renal and hepatic function, given use in high-dose conditioning regimens |
| Handling Protection | Cytotoxic drug handling precautions required, consistent with its classification as an alkylating chemotherapy agent |
Safety Considerations
Please refer to the SmPC for safety information. Key warnings, contraindications and drug interaction data are not available in this Evidence Pack; the missing prescribing label information (TFDA/EMA warnings and contraindications) has been flagged as a Blocking data gap that must be resolved before any safety pre-assessment (S1) can proceed.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: The predicted indication is supported by an L2 evidence level, including multiple completed Phase 2 trials and cohort studies that already use thiotepa-based high-dose chemotherapy in germ cell tumour patients — indicating the prediction largely formalizes existing off-label clinical practice rather than proposing a mechanistically novel use. However, the drug currently has no EU marketing authorization and lacks documented mechanism of action and safety label data, which prevents unconditional advancement.
To proceed, the following is needed:
- Resolve the Blocking data gap: obtain the official prescribing label (warnings, contraindications) from the relevant regulatory source
- Resolve the mechanism of action data gap via DrugBank or equivalent authoritative source
- Clarify current regulatory/marketing pathway, given the product has zero EU authorizations on record
- Note: nine related yolk sac tumour subtype predictions (ranks 2–9) generated by the same model carry no clinical trial or literature support (L5, Hold) and should not be advanced without further evidence
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.