Lapatinib
| Evidence Level: L5 | Predicted Indications: 1 |
Table of Contents
Lapatinib: From HER2-Positive Breast Carcinoma to Dermatofibrosarcoma Protuberans
One-Sentence Summary
Lapatinib was originally used to treat HER2-positive breast carcinoma. The TxGNN model predicts it may be effective for dermatofibrosarcoma protuberans (DFSP), but no clinical trials or publications currently support this prediction, so it rests on the model score alone.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | HER2-positive breast carcinoma |
| Predicted New Indication | Dermatofibrosarcoma protuberans |
| TxGNN Prediction Score | 0.9930 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (11 of 11) – CDSCO approval status is not included in this data |
| Number of Listed Products | 11 (valid: 11) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Lapatinib is known to be a dual EGFR/HER2 tyrosine kinase inhibitor, and its efficacy in HER2-positive breast carcinoma is established.
DFSP is typically driven by the COL1A1-PDGFB fusion, which causes constitutive PDGFR-beta activation, and it is usually treated with imatinib. A direct link between lapatinib’s EGFR/HER2 inhibition and this driver pathway has not been established. A plausible but unverified connection is through downstream signaling shared among receptor tyrosine kinases (such as PI3K/AKT and MAPK), or through EGFR involvement in some sarcomas.
The prediction should therefore be treated as a hypothesis, requiring preclinical validation before any clinical consideration.
India Market Information
Lapatinib is marketed in India as single-ingredient oral tablets. The approved indication text is not available for these registrations. The first five of the 11 are listed below.
| Authorization Number | Product Name | Dosage Form | Manufacturer |
|---|---|---|---|
| 125749 | Lanib 250 Tablet | Bottle of 30 tablets | BDR Pharmaceuticals Internationals Pvt |
| 75607 | Etibo 250mg Tablet | Bottle of 30 tablets | Samarth Life Sciences Pvt Ltd |
| 122886 | Libset Tablet | Bottle of 30 tablets | Intas Pharmaceuticals Ltd |
| 124425 | Lapahope 250mg Tablet | Bottle of 30 tablets | Glenmark Pharmaceuticals Ltd |
| 216089 | Tykerb 250mg Tablet | Bottle of 30 tablets | Glaxo SmithKline Pharmaceuticals Ltd |
Cytotoxicity
| Item | Content |
|---|---|
| Cytotoxicity Classification | Targeted therapy (EGFR/HER2 tyrosine kinase 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 | Liver function, cardiac function (including QT interval), electrolytes (notably potassium), and respiratory symptoms, based on the disease associations listed below |
| Handling Protection | Please refer to the package insert warnings and precautions |
Safety Considerations
- Disease associations flagged in the knowledge graph (not label text): long QT syndrome, familial long QT syndrome, torsades de pointes, liver failure, drug-induced liver injury, potassium deficiency disease, interstitial lung disease, heart failure.
- Drug Interactions: 549 interactions were identified. Major-level interactions include:
- Loperamide
- Clarithromycin
Moderate-level interactions include acid-suppressing agents (famotidine, ranitidine, cimetidine, omeprazole, rabeprazole, dexlansoprazole), corticosteroids (hydrocortisone, dexamethasone, betamethasone, triamcinolone, budesonide), aprepitant, pioglitazone, saxagliptin, and several laxatives or bowel-preparation agents.
Package insert warnings and contraindications were not available for this report; please refer to the package insert for label safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction rests only on a high TxGNN score. There are no clinical trials or publications, and no established mechanistic link between EGFR/HER2 inhibition and the PDGFB-driven biology of DFSP. Imatinib already addresses that driver pathway.
To proceed, the following is needed:
- Preclinical validation (for example, lapatinib activity in DFSP cell lines or models, and EGFR/HER2 expression in DFSP tissue)
- Mechanism of action data for lapatinib
- India package insert warnings and contraindications for safety screening
- Route compatibility assessment (oral tablets are marketed)
- A comparison against standard DFSP therapy (imatinib) to define any unmet need
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.