Voxelotor
| Evidence Level: L5 | Predicted Indications: 7 |
Table of Contents
Voxelotor: From Sickle Cell Anemia to Hereditary Thrombocytopenia with Normal Platelets
One-Sentence Summary
Voxelotor was originally used to treat sickle cell anemia (and is linked to hereditary persistence of fetal hemoglobin in the knowledge graph). The TxGNN model predicts it may be effective for hereditary thrombocytopenia with normal platelets, but currently there are 0 clinical trials and 0 publications supporting this direction, so the prediction rests on the model score alone.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Sickle cell anemia (the US license records contain no indication text; this comes from the knowledge graph) |
| Predicted New Indication | Hereditary thrombocytopenia with normal platelets |
| TxGNN Prediction Score | 99.58% |
| Evidence Level | L5 |
| US Market Status | Cancelled only (no active authorization) |
| Number of NDAs | 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. Voxelotor is generally known as a hemoglobin S polymerization inhibitor that increases hemoglobin-oxygen affinity, which is the basis of its use in sickle cell anemia.
That mechanism acts on red blood cells. There is no evident connection to platelet production or function, which is the area affected by the predicted indication. Because no mechanistic bridge can be verified, the high score (99.58%) most likely reflects similarity within the knowledge graph rather than a specific biological rationale.
The same pattern appears across the other predictions: six more platelet-related or unrelated conditions (such as macrothrombocytopenia with mitral valve insufficiency, dense granule disease, transient neonatal thrombocytopenia, thrombocytopenia, primary release disorder of platelets, and light chain-associated Fanconi syndrome) have scores between 99.0% and 99.6%. None has any trial or publication support.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
Currently no related literature available.
US Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| NDA216157 | OXBRYTA (Global Blood Therapeutics, a subsidiary of Pfizer) | Tablet, for suspension (oral) | Not listed; status: cancelled |
| NDA213137 | OXBRYTA (Global Blood Therapeutics, a subsidiary of Pfizer) | Tablet, film coated (oral) | Not listed; status: cancelled |
Both authorizations are cancelled, so there is currently no actively marketed voxelotor product in the US. This limits the practical feasibility of any repurposing effort.
Safety Considerations
- Drug Interactions: The interaction query returned 100 records. Among those listed, the following are Major:
- Dexamethasone
- Clarithromycin
- Eliglustat
- Naloxegol
Many others are Moderate, including hydrocortisone, prednisone, betamethasone, budesonide, triamcinolone, aprepitant, saxagliptin, naldemedine, nitisinone, repaglinide, simvastatin, and tinidazole. Corticosteroids are a prominent group among these interactions.
Please refer to the package insert for warnings and contraindications.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction is supported only by a knowledge-graph score. There are no clinical trials or publications, no plausible mechanistic link between hemoglobin-oxygen affinity modulation and the predicted platelet disorder, and no currently active US authorization.
To proceed, the following is needed:
- Mechanism of action data (for example from DrugBank) to test whether any biological bridge to platelet disorders exists
- Package insert warnings and contraindications, which are required before any safety screening
- Preclinical or literature evidence linking voxelotor to platelet production or function
- Clarification of the reasons for the cancellation of the US authorizations and of the regulatory path to supply the drug for any new study
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.