Mirtazapine
| Evidence Level: L5 | Predicted Indications: 3 |
Table of Contents
Mirtazapine: From Depression to Ohdo Syndrome and Variants
One-Sentence Summary
Mirtazapine is an antidepressant originally used for depressive disorders (unipolar depression, major depressive disorder) and anxiety disorder. The TxGNN model predicts it may be effective for Ohdo syndrome and variants, but there are currently no clinical trials and no publications supporting this direction, so it is a computational prediction only.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Unipolar depression, endogenous depression, major depressive disorder, anxiety disorder |
| Predicted New Indication | Ohdo syndrome and variants |
| TxGNN Prediction Score | 0.9942 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (at least 20) – CDSCO approval status is not included in this data |
| Number of Listed Products | at least 20 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Based on general pharmacological knowledge, mirtazapine is an antidepressant that acts through central alpha-2 adrenergic antagonism, 5-HT2/5-HT3 antagonism and H1 antagonism. Its efficacy in depression is established.
The link to the predicted indication is weak. Ohdo syndrome is a rare genetic neurodevelopmental disorder (blepharophimosis, intellectual disability, hypotonia), associated with chromatin-modifier defects such as KAT6B or MED12 variants, depending on the subtype. Mirtazapine’s monoaminergic pharmacology has no established connection to this pathology. The very high score (0.9942) comes from the TxGNN model (deep learning) and may reflect similarities the model learned between related diseases, not biological evidence. At most, benefit could be symptomatic (for example sleep, appetite or mood), and this is speculative.
Two other predictions were also generated, and they are equally unsupported:
- Blepharophimosis - intellectual disability syndrome, Ohdo type (score 0.9911): a closely related entity to the first prediction. The similar scores suggest the predictions are not independent. No plausible disease-modifying mechanism is evident.
- Benign paroxysmal torticollis of infancy (score 0.9911): an episodic movement disorder related to migraine equivalents, often linked to CACNA1A variants. Only a speculative, indirect link exists. The condition is self-limiting and managed supportively, and mirtazapine carries a boxed warning for suicidality in young patients and is not established in infants.
India Market Information
Mirtazapine has 20 valid single-ingredient registrations, all oral tablets (including mouth-dispersible and orally disintegrating forms). The approved indication text is not available for these registrations. Main examples:
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 140043 | Mirfit 15 Tablet (Ryon Pharma) | Strip of 10 tablets | Not specified |
| 146733 | Mitraford 30 Tablet (Oxpro Pharma) | Strip of 10 tablets | Not specified |
| 141002 | Mirtadep 15mg Tablet (Torrent Pharmaceuticals) | Strip of 10 tablets | Not specified |
| 136526 | Mirnite 7.5mg Tablet DT (Intas Pharmaceuticals) | Strip of 10 orally disintegrating tablets | Not specified |
| 139616 | Mirzat 7.5mg Tablet (Knoll Pharmaceuticals) | Strip of 10 tablets | Not specified |
Safety Considerations
- Contraindications / risk conditions (from knowledge graph disease associations, not label text): multiple system atrophy, postural orthostatic tachycardia syndrome, orthostatic hypotension, hypotensive disorder, epilepsy, manic bipolar affective disorder, liver disease, gallbladder disease, impaired renal function, neutropenia, agranulocytosis, hemoglobinopathy, hypertriglyceridemia, obesity disorder (including monogenic obesity), stroke and cerebrovascular disorder, cerebral infarction, myocardial infarction, coronary thrombosis, serotonin syndrome and drug-induced akathisia.
- Drug Interactions: 324 interactions were identified. Major-level interactions include:
- Bupropion
- Lorcaserin
- Dolasetron
- Palonosetron
Moderate-level examples include famotidine, cimetidine, loperamide, aprepitant, morphine, dexamethasone, clarithromycin, levofloxacin, dronabinol, nabilone, eliglustat, obeticholic acid and several bowel-preparation laxatives.
- Special population note: Mirtazapine carries a boxed warning for suicidality in young patients, and its use in infants is not established. This is particularly relevant for the paediatric indications predicted here.
Conclusion and Next Steps
Decision: Hold
Rationale: All three predictions are supported by model scores only. There are no clinical trials or publications, and no plausible mechanistic link between mirtazapine’s monoaminergic pharmacology and the genetic or developmental nature of these conditions. The target populations are also paediatric, which raises the safety bar.
To proceed, the following is needed:
- Mechanism of action data for mirtazapine from DrugBank
- Package insert warnings and contraindications from the India product labels (currently unavailable, which blocks safety screening)
- Preclinical or mechanistic evidence linking mirtazapine to the pathways involved in Ohdo syndrome or benign paroxysmal torticollis of infancy
- A review of whether any symptomatic benefit (sleep, appetite, mood) is clinically relevant, with a paediatric safety assessment
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.