Romiplostim
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
- Romiplostim
- Pharmacist Assessment Report
- Romiplostim: From Immune Thrombocytopenia to Primary Release Disorder of Platelets
- One-Sentence Summary
- Quick Overview
- Why is This Prediction Reasonable?
- Clinical Trial Evidence
- Literature Evidence
- Australia Market Information
- Safety Considerations
- Conclusion and Next Steps
- Disclaimer
Romiplostim: From Immune Thrombocytopenia to Primary Release Disorder of Platelets
One-Sentence Summary
Romiplostim (Nplate) is a thrombopoietin receptor agonist whose recorded uses in the knowledge graph include aplastic anaemia and autoimmune thrombocytopenia. The TxGNN model predicts it may be effective for primary release disorder of platelets, but no clinical trials and only 1 mechanistic publication (on immune thrombocytopenia, a different disease) are available. This prediction rests on the model score alone.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Relations recorded in the knowledge graph: idiopathic aplastic anaemia, aplastic anaemia, autoimmune thrombocytopenia (the local ARTG record contains no indication text) |
| Predicted New Indication | Primary release disorder of platelets |
| TxGNN Prediction Score | 1.0000 |
| Evidence Level | L5 |
| Australia Market Status | Listed on the PBS Schedule (1 of 1 items) – TGA (ARTG) registration status is not included in this data |
| Number of PBS Items | 1 (valid: 1) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. From the pharmacology record, romiplostim is a peptide agonist of the thrombopoietin receptor (MPL), which stimulates megakaryocyte maturation and platelet production.
Primary release disorder of platelets is a qualitative defect in platelet function. Raising the platelet count would not be expected to correct a defect in how platelets function, so the mechanistic link is weak. The only linked paper (PMID 25682608) describes autoantibodies inhibiting proplatelet formation in immune thrombocytopenia, which is a different disease mechanism. The very high model score is not backed by clinical evidence.
Other predicted conditions follow a similar pattern. Pseudo-von Willebrand disease, Glanzmann thrombasthenia, Scott syndrome, collagen receptor defects and platelet-type bleeding disorders are mostly function defects, where a platelet-count-raising drug has no clear rationale. Fetal and neonatal alloimmune thrombocytopenia (rank 4) is the most plausible hypothesis, because it is an immune-mediated thrombocytopenia related to the immune thrombocytopenia setting. The evidence for it is indirect, however (see below).
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
The one publication linked to the top-ranked prediction:
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 25682608 | 2015 | Basic/mechanistic research | Haematologica | Antiplatelet autoantibodies from immune thrombocytopenia patients inhibited proplatelet formation by megakaryocytes in vitro. This concerns a different disease. |
For the fourth-ranked prediction (fetal and neonatal alloimmune thrombocytopenia), only indirect literature exists and no study addresses that disease directly:
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 31239245 | 2019 | Review | Blood Advances | Romiplostim in paediatric immune thrombocytopenia: drug development and current practice |
| 34711622 | 2021 | Case report | BMJ Case Reports | Management of refractory immune thrombocytopenia in pregnancy |
| 23822831 | 2013 | Case report | Eur J Haematol | Complete remission of refractory immune thrombocytopenia after a short course of romiplostim |
| 20410910 | 2010 | Review/commentary | J Perinatol | Whether novel thrombopoietic agents should be introduced in neonatal care |
| 27605856 | 2016 | Case report | Asian J Transfus Sci | Refractory immune thrombocytopenia in pregnancy managed with eltrombopag (not romiplostim) |
| 23257464 | 2012 | Review | Zhongguo Shi Yan Xue Ye Xue Za Zhi | Advances in thrombopoietic drugs for childhood immune thrombocytopenia |
Australia Market Information
| ARTG Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| ARTG 9696H | Nplate | Powder for injection 375 micrograms | Not stated in the available record |
Safety Considerations
- Drug Interactions:
- Carfilzomib: Major interaction (DDInter).
- Thrombopoietin receptor (MPL): the pharmacological target of romiplostim, listed in the pharmacology record rather than as a clinical interaction.
Please refer to the TGA-approved Product Information (PI) for warnings and contraindications. Placental transfer and fetal or neonatal safety remain unresolved for the alloimmune thrombocytopenia hypothesis.
Conclusion and Next Steps
Decision: Hold
Rationale: No clinical trial or publication directly studies primary release disorder of platelets, so the evidence level is L5. The mechanism (raising platelet count) does not match a qualitative platelet function defect. The model score alone is not enough to justify progression.
To proceed, the following is needed:
- Mechanism of action data and TGA PI warnings and contraindications (currently missing)
- Direct clinical or mechanistic evidence in the predicted disease
- For the more plausible fetal and neonatal alloimmune thrombocytopenia hypothesis: disease-specific studies and a dedicated safety assessment covering placental transfer and neonatal platelet response
- For inherited thrombocytopenias: subtype-specific evidence, since the category is too heterogeneous to assess
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.