Tipiracil

Evidence Level: L5

Predicted Indications: 9

Tipiracil

Pharmacist Assessment Report

Tipiracil: From Colorectal Cancer to Cecum Villous Adenoma

One-Sentence Summary

Tipiracil is a component of the trifluridine/tipiracil combination (marketed in Canada as LONSURF), originally used to treat colorectal cancer. The TxGNN model predicts it may be effective for cecum villous adenoma, but no clinical trials and no publications currently support this prediction, so it rests on the model score alone.

Quick Overview

Item	Content
Original Indication	Colorectal cancer (malignant colon neoplasm, colonic neoplasm, squamous cell carcinoma of colon)
Predicted New Indication	Cecum villous adenoma
TxGNN Prediction Score	0.9999
Evidence Level	L5
Canada Market Status	Marketed (marketed DINs: 2 of 2)
Number of DINs	2 (marketed: 2)
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available in the data compiled for this report. Based on known information, tipiracil is a thymidine phosphorylase inhibitor. It is marketed only in combination with trifluridine, a cytotoxic nucleoside analogue, for metastatic colorectal cancer. Tipiracil prevents rapid breakdown of trifluridine, which raises its exposure and antitumour activity.

A villous adenoma of the cecum is anatomically and histologically related to colorectal neoplasia, which probably explains the high model score. However, it is a benign, premalignant lesion. There is no evidence that a cytotoxic combination would be appropriate for it, and the mechanism has not been documented for this indication. The prediction should be treated as a hypothesis only.

Other top-ranked predictions show the same pattern:

Benign lesions (colon lipoma, leiomyoma, lymphangioma, cavernous hemangioma): no plausible link to the drug’s mechanism.
Cecum neuroendocrine tumor G1: low proliferative index, so antimetabolite activity is unlikely to be effective.
Colorectal gastrointestinal stromal tumor: driven by KIT/PDGFRA mutations and generally resistant to conventional cytotoxic chemotherapy.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

No literature directly supports the predicted indication of cecum villous adenoma. Publications retrieved for other lower-ranked predictions only concern the approved colorectal cancer use or its safety, for example:

PMID	Year	Type	Journal	Key Findings
32655959	2020	Case report	Case Rep Oncol Med	Readministration of cancer drugs in a patient with chemorefractory metastatic colorectal cancer (cecal carcinoma)
30677817	2018	Case report	Dermatol Online J	Leukocytoclastic vasculitis with late-onset Henoch-Schönlein purpura after trifluridine/tipiracil in metastatic appendiceal cancer

These are not evidence for the predicted indication.

Canada Market Information

DIN	Product Name	Dosage Form	Approved Indication
02472104	LONSURF	Not specified	Not specified
02472112	LONSURF	Not specified	Not specified

Cytotoxicity

Tipiracil is used only in combination with the cytotoxic agent trifluridine, which is used for colorectal cancer.

Item	Content
Cytotoxicity Classification	Conventional cytotoxic combination (trifluridine, a nucleoside analogue, plus tipiracil, a thymidine phosphorylase 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; haematological parameters (CBC) are generally monitored with cytotoxic agents
Handling Protection	Follow cytotoxic drug handling regulations

Safety Considerations

Drug Interactions: 14 interaction records were found. Thirteen are rated Moderate:
- Cimetidine
- Tafenoquine
- Ketoconazole
- Brigatinib
- Crizotinib
- Encorafenib
- Ethinylestradiol
- Lenvatinib
- Medroxyprogesterone acetate
- Megestrol acetate
- Ribociclib
- Rucaparib
- Vandetanib
The remaining record is a pharmacology entry showing tipiracil binding to the SARS-CoV-2 non-structural protein 15 target, with no severity rating.
Literature safety signal: One case report described leukocytoclastic vasculitis with Henoch-Schönlein purpura after trifluridine/tipiracil treatment.

Please refer to the package insert for warnings and contraindications.

Conclusion and Next Steps

Decision: Hold

Rationale: The prediction for cecum villous adenoma is supported by model score only (L5), with no trials or literature. The disease is a benign, premalignant lesion, and exposing patients to a cytotoxic combination is hard to justify without supporting evidence. None of the other top-ranked predictions has direct evidence either.

To proceed, the following is needed:

Mechanism of action data and a documented rationale for a premalignant or benign lesion
Health Canada package insert warnings and contraindications, which are required before any safety screening
Preclinical or early clinical data for the predicted indication
A risk-benefit assessment of cytotoxic treatment for a benign lesion
Approved indication text and dosage form details for the two DINs
Disclaimer

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