Cariprazine

證據等級: L5

預測適應症: 10 個

Cariprazine: From Schizophrenia / Bipolar I Disorder to Retinal Dystrophy with Extraocular Anomalies

One-Sentence Summary

Cariprazine is an atypical antipsychotic with preferential affinity for dopamine D3/D2 receptors and partial agonist activity at 5-HT1A receptors, established globally for the treatment of schizophrenia and bipolar I disorder — though not currently registered in Taiwan. The TxGNN model predicts it may have activity in Retinal Dystrophy with or without Extraocular Anomalies, theoretically grounded in the expression of D2/D3 receptors within retinal tissue and dopamine’s role in photoreceptor signalling. Supporting evidence consists of 0 clinical trials and 15 publications retrieved on the topic of ophthalmic anomalies — none of which directly study Cariprazine in this indication, yielding an overall evidence level of L5.

Quick Overview

Item	Content
Original Indication	Schizophrenia / Bipolar I Disorder (not registered in Taiwan; globally approved)
Predicted New Indication	Retinal Dystrophy with or without Extraocular Anomalies
TxGNN Prediction Score	98.70%
Evidence Level	L5
Taiwan Market Status	Not marketed
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available in this Evidence Pack. Based on mechanistic context embedded in the repurposing rationale, Cariprazine acts as a D3-preferential dopamine D2/D3 partial agonist with additional 5-HT1A partial agonist activity — a profile consistent with its established antipsychotic use. D3 receptor preferential binding distinguishes Cariprazine from older antipsychotics and underlies its activity in both positive and negative symptoms of schizophrenia.

The mechanistic hypothesis linking Cariprazine to retinal dystrophy rests on a well-described but underexplored observation: dopamine D2 and D3 receptors are expressed in the inner retina, where dopamine released by amacrine cells modulates photoreceptor adaptation, retinal ganglion cell signalling, and light/dark adaptation cycles. There is animal-model evidence that retinal dopamine signalling influences eye growth and photoreceptor viability. In this framework, a D3/D2 partial agonist could theoretically provide neuroprotective support to degenerating photoreceptors.

However, retinal dystrophies are fundamentally genetic, progressive diseases — typically driven by mutations in genes such as RPGR, PRPF31, CRB1, USH2A, and many others — causing structural photoreceptor loss that dopaminergic modulation cannot repair. The Evidence Pack’s own assessment rates this a “highly speculative link” with no direct mechanistic chain between D2/D3 signalling and the genetic pathophysiology of retinal dystrophy. The TxGNN score of 98.70% reflects algorithmic similarity in the knowledge graph topology rather than pharmacological plausibility.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

The PubMed search retrieved 15 publications on the topic of retinal dystrophy with extraocular anomalies. None of these articles study Cariprazine or any dopaminergic agent in this indication; they address general ophthalmic and orbital pathology (orbital infections, diplopia, congenital motility disorders, lens anomalies, inherited metabolic eye disease). They are listed below for completeness, but none constitute direct supporting evidence for this repurposing hypothesis.

PMID	Year	Type	Journal	Key Findings
38321238	2024	Review	Pediatric Radiology	Imaging features of pediatric ocular pathologies including microphthalmos, coloboma, retinopathy of prematurity, Coats disease; no Cariprazine relevance
38249493	2023	Review	Taiwan Journal of Ophthalmology	Congenital lens shape anomalies, anterior segment dysgenesis, persistence of fetal vasculature; no Cariprazine relevance
33806565	2021	Other	Int J Mol Sciences	Optic nerve head and retinal abnormalities in CFEOM linked to KIF21A/TUBB3 mutations; no Cariprazine relevance
33447730	2020	Review	Therapeutic Advances in Ophthalmology	Eye involvement across inherited metabolic disorders (cornea, lens, retina, extraocular muscles); no Cariprazine relevance
30747268	2019	Other	Neuroradiology	Neuroradiological evaluation of ophthalmoplegia for differential diagnosis and treatment guidance; no Cariprazine relevance
30196776	2018	Other	J Binocular Vision Ocular Motility	Congenital cranial dysinnervation disorders (CCDDs) and ophthalmoplegia subtypes; no Cariprazine relevance
24932988	2014	Other	American Journal of Ophthalmology	Unified theory for maculopathy pathogenesis associated with cavitary optic disc anomalies; no Cariprazine relevance
24413161	2014	Case Report	J Neuro-Ophthalmology	Isolated trochlear-oculomotor synkinesis in a child — rare CCDD variant; no Cariprazine relevance
20127583	2010	Review	Seminars in Neurology	Systematic diagnostic approach to diplopia; ocular, neurologic, and extraocular muscle etiologies; no Cariprazine relevance
19064847	2008	Other	Archives of Ophthalmology	Clinical features and management of orbital arteriovenous malformations; no Cariprazine relevance

Taiwan Market Information

Cariprazine is not currently registered or marketed in Taiwan. No marketing authorization records are available. The drug is commercially available in the United States (Vraylar®) and the European Union (Reagila®) for schizophrenia and bipolar I disorder.

Safety Considerations

Please refer to the SmPC for safety information.

Conclusion and Next Steps

Decision: Hold

Rationale: All 10 predicted indications for Cariprazine in this Evidence Pack are rated L5 — model prediction only, with no clinical trials and no directly relevant literature for any indication. The top prediction (retinal dystrophy with or without extraocular anomalies) has a mechanistic rationale that is highly speculative: while D2/D3 receptor expression in the retina provides a theoretical entry point, retinal dystrophies are genetically driven structural degenerations with no established link to dopaminergic pharmacotherapy. Additionally, critical drug-level data (formal contraindications, Taiwan prescribing information, and detailed MOA documentation) are unavailable, placing the candidate at decision stage S0. Proceeding to any development activity is not justified at this time.

To proceed, the following is needed:

MOA confirmation: Retrieve and document Cariprazine’s full receptor binding profile and pharmacodynamic data from DrugBank and primary pharmacology publications
Preclinical evidence: Identify or commission studies testing a D3/D2 partial agonist specifically in a retinal dystrophy model (e.g., rd10 mouse, RPGR-knockout) before any clinical hypothesis is formed
Targeted literature search: Conduct a focused search on “dopamine AND retinal dystrophy AND neuroprotection” to determine whether the mechanistic hypothesis has any existing in vivo or in vitro support independent of TxGNN
Safety baseline: Review the EMA SmPC (Reagila®) and US prescribing information (Vraylar®) for contraindications, metabolic risks, and CNS adverse effects relevant to an ophthalmic patient population
Regulatory gap: Clarify the path to Taiwan registration before any local development investment is planned
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.