Clozapine
| Evidence Level: L2 | Predicted Indications: 9 |
Table of Contents
Clozapine: Manic bipolar affective disorder
One-Sentence Summary
Clozapine is an atypical antipsychotic that acts on several receptor systems, including dopamine D2 and serotonin 5-HT2A receptors. The TxGNN model predicts it may be effective for manic bipolar affective disorder, with 1 completed Phase 2 trial and a 2020 systematic review and meta-analysis supporting this direction, mostly in treatment-resistant patients.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Manic bipolar affective disorder |
| TxGNN Prediction Score | 0.9995 |
| Evidence Level | L2 |
| 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 | Proceed with Guardrails |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Based on known pharmacology, clozapine blocks dopamine D2 and serotonin 5-HT2A receptors and also acts on muscarinic and adrenergic receptors. This broad profile plausibly supports antimanic and mood-stabilising effects.
Mania and psychotic illness share dopaminergic and serotonergic disturbances, and antipsychotics are already widely used in acute mania. The strongest support comes from treatment-refractory patients, for whom conventional treatments have failed or were not tolerated.
A completed Phase 2 double-blind trial and a systematic review and meta-analysis point in this direction. The evidence base is small, however, and mainly covers refractory populations, so it should not be extended to all patients with mania.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00029458 | Phase 2 | Completed | 42 | Double-blind study of the safety and efficacy of clozapine in treatment-resistant mania, with an accompanying pathophysiology study |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 32182485 | 2020 | Systematic review/meta-analysis | J Psychiatr Res | Assessed the efficacy and adverse-effect profile of clozapine in bipolar disorder |
| 25346322 | 2015 | Systematic review | Bipolar Disord | Efficacy and safety of clozapine in treatment-resistant bipolar disorder |
| 41192460 | 2025 | Cohort/effectiveness study | Lancet Psychiatry | Nationwide and meta-analytic comparison of clozapine with other antipsychotics across psychiatric disorders |
| 33460070 | 2020 | Review | Acta Psychiatr Scand | Evidence-based options for managing a manic episode, including mood stabiliser and antipsychotic choice |
| 16432528 | 2006 | Review | Mol Psychiatry | Treatment-resistant bipolar disorder and options for inadequate response |
| 11280956 | 2001 | Review | Bull Menninger Clin | Treatment-resistant bipolar disorder; newer treatments rest mainly on case reports and case series |
| 10682225 | 2000 | Case series | Clin Neuropharmacol | 36 patients given combined ECT and clozapine; 67% benefited, adverse reactions in 16.6% |
| 41262335 | 2025 | Modelling study | Drug Des Devel Ther | Model-informed precision dosing to manage clozapine drug interactions in bipolar disorder |
India Market Information
Clozapine is marketed in India. The data compiled for this report show at least 20 valid single-ingredient registrations, and the list may be partial. Approved indication text is not recorded for any of them.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 82346 | Ericloza 100 Tablet | Strip of 10 tablets | Not specified |
| 205850 | Sizolam 100mg Tablet | Strip of 10 tablets | Not specified |
| 1409 | Alkepin Odt 50mg Tablet | Strip of 10 tablets | Not specified |
| 45310 | Clonex 50mg Tablet | Strip of 10 tablets | Not specified |
| 193052 | Restopax 50mg Tablet | Strip of 15 tablets | Not specified |
Safety Considerations
- Contraindications flagged in the data compiled for this report (taken from disease-association data, not label text): neutropenia, agranulocytosis, leukopenia, epilepsy, liver disease, orthostatic hypotension, coronary artery disease, stroke and cerebrovascular disorders, diabetes mellitus and diabetic ketoacidosis, hyperglycaemia, angle-closure glaucoma, benign prostatic hyperplasia, paralytic ileus, respiratory failure, heart conduction disease and sudden cardiac arrest.
- Drug Interactions: 449 interactions are recorded. Major-level interactions include bupropion, morphine and potassium citrate. Moderate ones include metformin, pioglitazone, famotidine, omeprazole, cimetidine, atropine, epinephrine and loperamide.
- Published safety literature on clozapine highlights agranulocytosis, myocarditis and cardiomyopathy, seizures, and metabolic risk, so blood count monitoring and cardiac and metabolic surveillance are essential.
Package insert warnings and contraindications were not available and should be reviewed before any use.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: A completed placebo-controlled Phase 2 trial in treatment-resistant mania and a systematic review and meta-analysis support clozapine in this setting, but there are no Phase 3 trials (Evidence Level L2). The evidence is modest, and the drug carries serious haematological, cardiac, seizure and metabolic risks, so use should be limited to refractory cases.
To proceed, the following is needed:
- Larger confirmatory randomised trials in treatment-resistant mania
- Review of package insert warnings and contraindications
- Mechanism of action data
- A monitoring plan covering absolute neutrophil count, cardiac and metabolic surveillance, and drug interaction management
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.