Mirtazapine
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Mirtazapine: From Depression to Ohdo Syndrome and Variants
One-Sentence Summary
Mirtazapine is an antidepressant originally used for depression (including major depressive disorder and anxiety-related conditions). The TxGNN model predicts it may be effective for Ohdo syndrome and variants, a rare genetic neurodevelopmental disorder, but there are currently 0 clinical trials and 0 publications supporting this prediction. It is a computational signal only.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Unipolar depression / major depressive disorder (the Singapore licence records contain no approved-indication text) |
| Predicted New Indication | Ohdo syndrome and variants |
| TxGNN Prediction Score | 99.42% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 5 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the compiled data. Mirtazapine is a monoaminergic antidepressant. It is generally understood to act through alpha-2 adrenergic antagonism and 5-HT2/5-HT3/H1 receptor blockade, which enhances noradrenergic and serotonergic transmission.
Ohdo syndrome is a rare genetic neurodevelopmental disorder (KAT6B-related). Its biology has no plausible connection to this mechanism, and no mechanistic link has been established. The high TxGNN score reflects patterns in a knowledge graph, not biological or clinical reasoning. The prediction should be treated as a hypothesis without support.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
Currently no related literature available.
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN14012P | APO-Mirtazapine Tablet 30 mg | Film-coated tablet | Not listed |
| SIN13644P | Mirtazapine Sandoz Orodispersible Tablets 30 mg | Orally disintegrating tablet | Not listed |
| SIN13643P | Mirtazapine Sandoz Orodispersible Tablets 15 mg | Orally disintegrating tablet | Not listed |
| SIN12527P | Remeron SolTab 30 mg | Tablet | Not listed |
| SIN12526P | Remeron SolTab 15 mg | Tablet | Not listed |
All five licences are valid single-ingredient oral products.
Safety Considerations
Package insert warnings and contraindications were not available in the compiled data. Please refer to the package insert for full safety information.
- Drug Interactions: 100 interactions are recorded. The 20 reviewed include these major-level ones:
- Bupropion
- Lorcaserin
- Dolasetron
- Palonosetron
Many others are moderate-level (e.g., clarithromycin, cimetidine, morphine, levofloxacin).
- Knowledge-graph contraindication associations (not label text; they need verification against the package insert):
- Neurological and psychiatric: epilepsy, manic bipolar disorder, serotonin syndrome, drug-induced akathisia, multiple system atrophy
- Haematological: neutropenia, agranulocytosis, hemoglobinopathy
- Cardiovascular and cerebrovascular: orthostatic hypotension, postural orthostatic tachycardia syndrome, hypotensive disorder, stroke and cerebrovascular disorders, myocardial infarction
- Hepatic, renal and metabolic: liver disease, gallbladder disease, impaired renal function, hypertriglyceridemia, obesity
- The predicted use would likely involve paediatric or infant patients, which raises additional safety concerns.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction rests only on a knowledge-graph score. There are no trials or publications, and no biological rationale links a monoaminergic antidepressant to a KAT6B-related genetic disorder. The same applies to the closely related entries in the model's list, such as the Ohdo-type blepharophimosis syndrome.
To proceed, the following is needed:
- Mechanism-of-action data and a credible biological hypothesis connecting mirtazapine to Ohdo syndrome
- Preclinical or case-level evidence of benefit
- Package insert warnings and contraindications (not yet obtained)
- A paediatric safety assessment
Note on other candidates: Other predictions for this drug have stronger evidence and may be better directions to pursue:
- Social phobia and phobic disorder: two randomized, placebo-controlled trials (small, with mixed results)
- Dysthymic disorder: one completed Phase 2/3 trial and class-level meta-analysis support
- Melancholia and neurotic depression: largely overlap with the existing depression indication
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.