Cytarabine

證據等級: L5

預測適應症: 9 個

Cytarabine: From Acute Leukemia to Small Cell Lung Carcinoma

One-Sentence Summary

Cytarabine is a pyrimidine antimetabolite classically used in the treatment of acute leukemia (AML/ALL). The TxGNN model predicts it may be effective for Small Cell Lung Carcinoma, with 3 clinical trials and 20 publications currently supporting this direction — though most of this evidence originates from historical (1980s–1990s) chemotherapy regimens rather than the current standard of care for SCLC.

Quick Overview

Item	Content
Original Indication	Not available from license/regulatory records (no German market authorization on file); classical literature-documented indication is acute leukemia (AML)
Predicted New Indication	Small Cell Lung Carcinoma
TxGNN Prediction Score	99.78%
Evidence Level	L3
Germany 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 (DrugBank MOA field is a data gap). Based on known pharmacology, cytarabine is a cytidine analog that is intracellularly phosphorylated to Ara-CTP, which is incorporated into DNA and inhibits DNA polymerase, blocking DNA synthesis in the S-phase of the cell cycle. This S-phase specificity makes it broadly cytotoxic to rapidly dividing malignant cells, which historically supported its use against leukemias.

Small cell lung carcinoma is one of the most rapidly proliferating solid tumors, sharing the high-growth-fraction biology that made cytarabine effective in leukemia. This mechanistic overlap was explored clinically in the 1980s, when cytarabine (Ara-C) was combined with cisplatin, vindesine, or cyclophosphamide/doxorubicin/vincristine (CAV) regimens for both SCLC and NSCLC.

However, the current standard of care for SCLC (etoposide plus platinum) has since superseded cytarabine-containing regimens, and no contemporary registered trial tests cytarabine specifically in SCLC. The mechanistic rationale is biologically plausible but reflects a clinical role that has already been replaced by newer agents — supporting a research/hypothesis-generating framing rather than a near-term repurposing candidate.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT03507244	Phase 1/2	Completed	34	Intrathecal pemetrexed (not cytarabine) combined with radiotherapy for leptomeningeal metastasis from solid tumors; low direct relevance to cytarabine/SCLC
NCT03101579	Phase 1	Completed	13	Intrathecal pemetrexed for recurrent leptomeningeal metastasis from NSCLC; cytarabine mentioned only as a historical comparator drug, not tested
NCT00863512	Phase 3	Terminated	34	Adjuvant chemotherapy (vinorelbine/cisplatin/docetaxel/gemcitabine/pemetrexed) vs. observation in early-stage NSCLC; cytarabine not part of the tested regimens, disease is NSCLC not SCLC

Note: None of the currently registered trials directly test cytarabine in small cell lung carcinoma; all three are low-relevance (Grade C).

Literature Evidence

PMID	Year	Type	Journal	Key Findings
232239	1979	Clinical trial (historic)	Medical and Pediatric Oncology	Cyclophosphamide + Adriamycin + cytosine arabinoside plus radiotherapy in 20 previously untreated SCLC patients
6095640	1984	Clinical study	American Journal of Clinical Oncology	Continuous-infusion Ara-C alone showed no responses with severe toxicity in relapsed SCLC; Ara-C added to CAV in extensive-stage disease
2841844	1988	Clinical study	American Journal of Clinical Oncology	Etoposide (VP-16) + infusional Ara-C in 17 patients with combination-refractory relapsed SCLC
2157307	1990	Phase II trial (NSCLC)	Tumori	Cisplatin + vindesine + cytarabine in 32 advanced NSCLC patients; 18% response rate
2156598	1990	Phase II trial (NSCLC)	Cancer	High-dose cytarabine (3 g/m²) + cisplatin in chemo-naive NSCLC; 14% response rate, but Grade IV myelosuppression in 32% of patients
2820740	1987	Pilot study (NSCLC)	European Journal of Cancer & Clinical Oncology	Cisplatin + cytarabine combination pilot study in advanced NSCLC
6264785	1981	Case series	American Journal of Medicine	Intensive chemotherapy (historically including cytarabine) for meningeal carcinomatosis in SCLC; 78% response rate
28223673	2017	Case report	Gan to Kagaku Ryoho	Multidisciplinary treatment of meningeal carcinomatosis in a SCLC patient
75105	1978	Phase II trial (EORTC)	European Journal of Cancer	Phase II study of anhydro-ara-5-fluorocytidine (an Ara-C analog) across several tumor types including SCLC
348088	1978	Review	Antibiotics and Chemotherapy	Review of Ara-C analogs (cyclocytidine, AAFC, N4-acyl derivatives) developed to overcome cytidine deaminase inactivation

Germany Market Information

Cytarabine currently has no marketing authorization on file in Germany (total_licenses = 0). No authorization number, product name, dosage form, or approved indication data is available for this dataset.

Cytotoxicity

Item	Content
Cytotoxicity Classification	Conventional cytotoxic (pyrimidine antimetabolite / nucleoside analog)
Myelosuppression Risk	High — literature-documented Grade III/IV myelosuppression in up to 46% of patients with high-dose regimens (PMID 2156598)
Emetogenicity Classification	Moderate to High (dose-dependent; high-dose regimens are classified as highly emetogenic)
Monitoring Items	CBC with differential and platelets, liver and renal function, neurologic exam (cerebellar toxicity risk with high-dose therapy), ocular exam (conjunctivitis risk with high-dose therapy)
Handling Protection	Must follow cytotoxic/hazardous drug handling regulations

Safety Considerations

Please refer to the package insert for safety information. (Detailed German/EU label warnings, contraindications, and drug interaction data are not yet available for this candidate — see Data Gap DG001, flagged as Blocking for safety evaluation.)

Conclusion and Next Steps

Decision: Hold

Rationale: Evidence for cytarabine in small cell lung carcinoma is limited to historical (1980s) chemotherapy regimens that have since been superseded by platinum/etoposide as standard of care, no currently registered trial tests cytarabine specifically in SCLC, and a Blocking data gap (missing label warnings/contraindications) prevents this candidate from formally entering the S1 safety evaluation stage.

To proceed, the following is needed:

Resolve DG001: obtain German/EU-approved label safety data (warnings, contraindications) from BfArM
Resolve DG002: obtain detailed mechanism of action data from DrugBank
Identify whether any contemporary (post-2000) trials or real-world evidence support cytarabine's role in SCLC, given the field has moved to newer regimens
Confirm route compatibility, since route_compatibility.status is currently unresolved for this indication
Disclaimer

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