Avapritinib

Evidence Level: L5

Predicted Indications: 9

Avapritinib

Pharmacist Assessment Report

Avapritinib: KIT/PDGFRA kinase inhibitor → axial spondylometaphyseal dysplasia

One-Sentence Summary

Avapritinib is a KIT/PDGFRA kinase inhibitor marketed in Canada under the brand AYVAKYT. The TxGNN model predicts it may be relevant to axial spondylometaphyseal dysplasia, a rare skeletal disorder, but no clinical trials and no publications were found to support this prediction, so it remains a model-only signal.

Quick Overview

Item	Content
Original Indication	Not recorded in the local data
Predicted New Indication	axial spondylometaphyseal dysplasia
TxGNN Prediction Score	0.9992
Evidence Level	L5
Canada Market Status	Marketed (marketed DINs: 4 of 4)
Number of DINs	4 (marketed: 4)
Recommended Decision	Hold

Why is This Prediction Reasonable?

Detailed mechanism of action data is not available in the data compiled for this report. Avapritinib is generally known as an inhibitor of the KIT and PDGFRA kinases.

Axial spondylometaphyseal dysplasia is a rare skeletal disorder reported to be linked to CFAP410 (C21orf2). No involvement of KIT or PDGFRA is known, so no mechanistic link can be established from the available data. The TxGNN score reflects a computational prediction only and should not be read as evidence of efficacy. A kinase inhibitor given after birth is also unlikely to correct a structural developmental skeletal condition.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

Currently no related literature available.

Canada Market Information

DIN	Product Name	Dosage Form	Approved Indication
02551764	AYVAKYT	Not recorded	Not recorded
02551780	AYVAKYT	Not recorded	Not recorded
02551799	AYVAKYT	Not recorded	Not recorded
02551772	AYVAKYT	Not recorded	Not recorded

All four single-ingredient licences are currently valid.

Cytotoxicity

Item	Content
Cytotoxicity Classification	Targeted therapy (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	Please refer to the package insert warnings and precautions; typically includes blood counts and liver function
Handling Protection	Please refer to the package insert warnings and precautions

Safety Considerations

Drug Interactions: 100 potential interactions were identified in the interaction database; 20 are listed in the data compiled for this report.
- Major: aprepitant, acetylsalicylic acid, clarithromycin, dexamethasone, cobicistat, deferasirox, deferiprone, ibritumomab tiuxetan, tositumomab (I-131), samarium (153Sm) lexidronam
- Moderate: cimetidine, clotrimazole, dexfenfluramine, fenfluramine, glycerol phenylbutyrate, metreleptin, miconazole, sibutramine, troglitazone, strontium chloride Sr-89

Please refer to the package insert for warnings and contraindications.

Conclusion and Next Steps

Decision: Hold

Rationale: The prediction has no supporting trials or publications (Evidence Level L5), and no plausible mechanistic link between KIT/PDGFRA inhibition and this disorder could be established. The very high score is a model output only.

To proceed, the following is needed:

Package insert warnings and contraindications from Health Canada
Detailed mechanism of action data
Preclinical or genetic evidence linking KIT/PDGFRA signalling to the disease
A safety and risk-benefit assessment for the target population, including the major drug interactions listed above
Disclaimer

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