Perampanel
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Perampanel: From Epilepsy (Focal/Generalized Seizures) to Visual Epilepsy
One-Sentence Summary
Perampanel is a selective, non-competitive AMPA-receptor antagonist originally developed and marketed internationally (in 35+ countries) as adjunctive therapy for focal-onset and primary generalized tonic-clonic seizures in epilepsy; it is not currently registered in Taiwan. The TxGNN model predicts it may be effective for Visual Epilepsy (a photosensitive/visually-induced reflex epilepsy subtype), with 3 clinical trials and 20 publications returned by the evidence search — though none of them are designed specifically for this seizure subtype, so the direct evidence is currently indirect.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not documented in structured regulatory/DrugBank data (Data Gap). Per published literature, perampanel is internationally approved as adjunctive treatment for focal (partial-onset) seizures with/without secondary generalization and primary generalized tonic-clonic seizures in epilepsy. |
| Predicted New Indication | Visual Epilepsy |
| TxGNN Prediction Score | 99.92% |
| Evidence Level | L4 (mechanistic/general-population trial and literature support; no study specific to visual epilepsy) |
| Taiwan Market Status | Not marketed (Not marketed) |
| Number of Registrations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed DrugBank-sourced mechanism-of-action data is flagged as a data gap in this evidence pack. Based on information consistently reported across the retrieved literature, perampanel is a selective, non-competitive antagonist of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) glutamate receptors, reducing glutamate-mediated postsynaptic neuronal excitation — a mechanism distinct from GABAergic or sodium-channel-based antiseizure drugs. This mechanism underlies its established efficacy in focal-onset and generalized tonic-clonic seizures.
Visual (photosensitive) epilepsy is characterized by photoparoxysmal responses driven by excessive glutamatergic excitation in the occipital cortex when triggered by visual stimuli (e.g., flickering light patterns). Because AMPA-receptor-mediated excitation is a plausible contributor to this cortical hyperexcitability, an AMPA antagonist such as perampanel has a coherent mechanistic rationale for suppressing photoparoxysmal/visually-triggered seizure activity — essentially an extension of its established broad-spectrum antiseizure action to a specific seizure trigger rather than a new therapeutic mechanism.
That said, all three retrieved clinical trials and all 20 literature items concern general epilepsy populations (tolerability/PK, EEG/cognition, neurophysiology testing) rather than a photosensitive/visual-epilepsy-specific cohort — the reviewers grading these trials scored the two most relevant items only “B”/”C” relevance precisely because the visually-induced seizure subtype was not a designed endpoint. The prediction should therefore be read as mechanistically plausible but clinically unconfirmed for this specific reflex-epilepsy subtype.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT03780907 | Phase 2 | Completed | 18 | Randomized, double-blind, placebo-controlled study of tolerability, safety, and PK of perampanel (E2007) in epileptic patients with partial and generalized seizures on concomitant AEDs; general safety/PK design, not visual-epilepsy-specific. |
| NCT02900755 | Phase 4 | Completed | 30 | Evaluated perampanel’s effects on cognition and EEG in general epilepsy patients; assesses adverse effects during AED introduction, not a photosensitive-epilepsy cohort. |
| NCT03653741 | Phase 4 | Completed | 12 | Assessed perampanel’s effects on EEG, somatosensory evoked potentials, brainstem auditory evoked potentials, and visual evoked potentials (VEP) in healthy volunteers; relevant to visual neurophysiology testing but not a visual-epilepsy treatment trial. |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 29898971 | 2018 | Review (Practice Guideline) | Neurology | AAN/AES guideline update on efficacy/tolerability of newer AEDs (including perampanel) for new-onset epilepsy. |
| 36206645 | 2022 | Systematic Review/Meta-analysis of RCTs | Seizure | Pooled efficacy and safety of perampanel across randomized controlled trials in focal and generalized-onset seizures. |
| 36878742 | 2023 | Systematic Review/Meta-analysis | Brain & Development | Efficacy, tolerability, and safety of perampanel in children and adolescents with epilepsy. |
| 36150304 | 2022 | Review | Epilepsy & Behavior | Perampanel monotherapy for focal-onset and generalized tonic-clonic seizures: clinical trial and real-world evidence. |
| 25878177 | 2015 | Post-hoc analysis of 3 Phase III RCTs | Neurology | Impact of concomitant enzyme-inducing AEDs on perampanel efficacy/safety across the pivotal Phase III trials. |
| 31912315 | 2020 | Cohort | Clinical Pharmacokinetics | Therapeutic drug monitoring of AEDs (including perampanel) in women with epilepsy before, during, and after pregnancy. |
| 37775491 | 2023 | Cohort | The Medical Journal of Malaysia | Real-world efficacy and safety of adjunctive perampanel in epilepsy patients. |
| 37329172 | 2023 | Cohort | Annals of Clinical and Translational Neurology | Efficacy of perampanel in pediatric epilepsy with known/presumed genetic etiology. |
| 36034267 | 2022 | Cohort | Frontiers in Neurology | Real-life effectiveness/tolerability of perampanel in childhood absence epilepsy. |
| 24559052 | 2014 | Review | Expert Opinion on Drug Discovery | Discovery and development history of perampanel as an AMPA-receptor antagonist antiepileptic. |
Note: None of the above trials or publications are designed specifically around visually-induced/photosensitive seizures — all are general epilepsy populations. This is consistent with the “L4” evidence level assigned.
Taiwan Market Information
Perampanel currently holds no marketing authorization in Taiwan (0 registrations; market status: Not marketed). No license records are available to summarize.
Safety Considerations
- Drug Interactions: A DDI query returned 56 total interactions (source: DDInter). Notable Moderate-level interactions include CNS depressants and opioids (morphine, codeine, hydrocodone, opium, difenoxin, diphenoxylate, dextromethorphan), sedating antihistamines (promethazine, chlorpheniramine, azelastine nasal), cannabinoids (dronabinol, nabilone), ethanol, dexamethasone, metoclopramide, sibutramine, and chloroquine/hydroxychloroquine — consistent with perampanel’s known CNS-depressant and dizziness/somnolence potentiation profile. One Minor-level interaction was noted with clarithromycin.
Package-insert-level warnings and contraindications are not available in this evidence pack (flagged as a Blocking data gap — see Conclusion).
Conclusion and Next Steps
Decision: Hold
Rationale: The mechanistic rationale (AMPA-receptor antagonism suppressing cortical hyperexcitability) is sound, but no clinical trial or publication in the evidence pack specifically targets visual/photosensitive epilepsy — all supporting evidence is drawn from general epilepsy populations. Combined with the absence of Taiwan regulatory registration and a Blocking data gap on TFDA label warnings/contraindications, this candidate is not yet ready to advance past a research question.
To proceed, the following is needed:
- TFDA (or equivalent) package-insert warnings and contraindications (currently a Blocking gap, DG001)
- Confirmed DrugBank mechanism-of-action record (currently a High-severity gap, DG002)
- Preclinical or clinical evidence specifically in a photosensitive/visually-induced seizure population (e.g., photoparoxysmal response suppression studies)
- A Taiwan market-access/registration pathway assessment, given the drug is not currently marketed locally
Additional note: Among the 10 TxGNN-predicted indications in this evidence pack, status epilepticus (rank 10, score 99.77%) shows materially stronger direct evidence — an L3 evidence level, multiple targeted Phase 2–4 trials (including an actively recruiting post-cardiac-arrest prophylaxis trial, NCT06401707), a 81-patient cohort study, and two tier-1 systematic reviews — and is already scored “Proceed with Guardrails.” Since status epilepticus therapy is a natural extension of perampanel’s core antiseizure mechanism rather than a cross-disease application, it may warrant separate, higher-priority evaluation alongside this visual-epilepsy candidate.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.