Methotrexate

證據等級: L5

預測適應症: 10 個

Methotrexate: From Unspecified Original Indications to Pulmonary Blastoma

One-Sentence Summary

Methotrexate (DrugBank DB00563) is a long-established antifolate agent, but this evidence pack does not contain a documented original indication, mechanism of action, or German marketing record for the drug. The TxGNN model predicts a possible new application in Pulmonary Blastoma, but this signal is currently supported by 0 clinical trials and 0 publications — it is a pure computational prediction with no corroborating clinical or mechanistic evidence.

Quick Overview

Item	Content
Original Indication	Not available — no approved indication text on record (drug currently not marketed in Germany)
Predicted New Indication	Pulmonary Blastoma
TxGNN Prediction Score	99.45%
Evidence Level	L5
Germany Market Status	✗ Not Marketed
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Detailed mechanism-of-action documentation for methotrexate is not available in this evidence pack (original_moa: Data Gap). Contextual information drawn from other candidate indications in this same dataset indicates that methotrexate acts as a dihydrofolate reductase (DHFR) inhibitor, blocking purine and thymidylate synthesis — a mechanism widely used in hematologic and CNS malignancies (e.g., CNS lymphoma, non-Hodgkin lymphoma, rhabdomyosarcoma) documented elsewhere in this dataset.

For the specific candidate indication evaluated here, pulmonary blastoma, no mechanistic rationale, clinical trial, or literature evidence was identified. The evidence pack's own rationale states: "Only a TxGNN model prediction score is available; there is no clinical trial or literature evidence supporting a mechanistic link or clinical use of methotrexate for this rare pulmonary blastoma." This means the prediction currently rests entirely on the graph-neural-network signal (Evidence Level L5), with no disease-specific scientific or clinical basis.

Clinical Trial Evidence

Currently no related clinical trials registered

Literature Evidence

Currently no related literature available

Germany Market Information

Methotrexate currently holds no marketing authorization in Germany in this dataset (0 licenses on record; market status: Not Marketed).

Cytotoxicity

Methotrexate is classified as an antineoplastic/cytotoxic agent (antimetabolite class), based on its established use in multiple chemotherapy regimens referenced throughout this evidence pack (e.g., CNS lymphoma, non-Hodgkin lymphoma, rhabdomyosarcoma, small cell lung carcinoma).

Item	Content
Cytotoxicity Classification	Conventional cytotoxic (Antimetabolite / Antifolate, DHFR inhibitor)
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	Must follow standard cytotoxic drug handling regulations (antimetabolite chemotherapy agent)

Safety Considerations

Please refer to the package insert for safety information.

Conclusion and Next Steps

Decision: Hold

Rationale: The TxGNN score for pulmonary blastoma is high, but there is no clinical trial or literature evidence specific to this rare tumor type, and drug-level data (MOA, TFDA/BfArM label warnings, contraindications, market status) are all unavailable, blocking any safety pre-assessment.

To proceed, the following is needed:

Resolve DG001 (Blocking): obtain TFDA/BfArM label warnings and contraindications
Resolve DG002 (High): confirm methotrexate's mechanism of action via DrugBank or equivalent source
Conduct a targeted literature/trial search specific to methotrexate in pulmonary blastoma
Confirm German marketing/licensing status, since 0 authorizations are currently on record

Note: This evidence pack also contains other candidate indications for methotrexate with substantially stronger evidence — notably Hodgkin lymphoma (Evidence Level L2, "Proceed with Guardrails," multiple historical Phase 2/3 regimens) and rhabdomyosarcoma (Evidence Level L2, "Research Question," Phase 2 trial evidence). These may warrant prioritized evaluation over the pulmonary blastoma signal assessed above.

Disclaimer

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