Memantine
| Evidence Level: L1 | Predicted Indications: 4 |
Table of Contents
Memantine: From Alzheimer’s Disease to Migraine Disorder
One-Sentence Summary
Memantine is an NMDA receptor antagonist, generally known for the treatment of moderate-to-severe Alzheimer’s disease (this original indication is based on general pharmacological knowledge and is not confirmed by regulatory data in this evidence pack — see Data Gaps DG001/DG002). The TxGNN model, together with real-world clinical and literature evidence, predicts memantine may be effective for Migraine Disorder (episodic migraine prophylaxis), with 2 clinical trials (including 1 completed Phase 3 RCT) and 20 publications — including a network meta-analysis, a systematic review, and multiple RCTs — currently supporting this direction.
Three further TxGNN candidates were also screened for this drug (pulmonary hypertension, kyphoscoliotic heart disease, migraine with brainstem aura); none currently have sufficient evidence and are addressed briefly in the Conclusion section.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Alzheimer’s disease (general knowledge; not confirmed by regulatory data in this evidence pack — Data Gap DG001/DG002) |
| Predicted New Indication | Migraine Disorder (episodic migraine prophylaxis) |
| TxGNN Prediction Score | 99.52% |
| Evidence Level | L1 |
| UK Market Status | Not Marketed (per available regulatory dataset) |
| Number of Marketing Authorisations | 0 |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data from DrugBank is not available for this drug (Data Gap DG002). Based on information drawn from the supporting literature, memantine is a non-competitive NMDA receptor antagonist. Glutamate/NMDA receptor signalling is implicated in cortical spreading depression and central sensitisation, both of which are core elements of migraine pathophysiology. This gives the prediction a plausible, well-articulated mechanistic rationale — considerably stronger than the other three candidate indications flagged for this drug, none of which have an established mechanistic link (see repurposing_rationale for pulmonary hypertension and kyphoscoliotic heart disease, both scored L5/Hold with no or irrelevant supporting literature).
Because the original indication (presumed Alzheimer’s disease/dementia) also centres on glutamatergic/NMDA receptor modulation in the CNS, the pharmacological rationale for repurposing towards a CNS excitability disorder such as migraine is coherent, even though the two conditions are clinically distinct. This mechanistic continuity is reflected in the volume of published clinical interest: at least 8 dedicated clinical/case-based publications on memantine specifically for migraine prophylaxis exist (spanning 2007–2025), plus a completed Phase 3 head-to-head RCT against sodium valproate — an established first-line migraine prophylactic agent.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrolment | Key Findings |
|---|---|---|---|---|
| NCT04698525 | Phase 3 | Completed | 33 | Head-to-head comparison of memantine vs sodium valproate for prophylactic treatment of episodic migraine; sodium valproate is an established Level A prophylactic, memantine was tested as an alternative for non-responders. Small sample size limits statistical power. |
| NCT02670161 | Phase 4 | Enrolling by invitation | 3,300 | Pragmatic EMR-based platform study across 10 common neurological disorders at NorthShore University HealthSystem; not a dedicated memantine–migraine trial, low direct relevance (relevance grade C). |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 26638119 | 2016 | RCT (double-blind, placebo-controlled) | Headache | Randomised placebo-controlled study of memantine for prophylaxis of migraine without aura, following earlier uncontrolled evidence of benefit. |
| 19280698 | 2009 | RCT/Open-label | Headache | Evaluates memantine in preventive treatment of migraine and refractory migraine. |
| 33961371 | 2021 | Meta-analysis of RCTs | Clinical Neuropharmacology | Systematic review/meta-analysis exploring memantine vs placebo efficacy for migraine; notes efficacy remains controversial. |
| 34352118 | 2021 | Systematic Review | Headache | Assesses efficacy and safety of memantine for prophylactic treatment of episodic migraine. |
| 40978493 | 2025 | Network Meta-analysis | Frontiers in Pharmacology | Compares comparative effectiveness and safety of oral preventive migraine medications (adults 18–65) across multiple agents. |
| 39467289 | 2024 | Clinical Practice Guideline | Annals of Internal Medicine | 2023 US VA/DoD Clinical Practice Guideline for headache management, covering migraine/TTH treatment and prevention recommendations. |
| 36869904 | 2023 | Review | Naunyn-Schmiedeberg’s Archives of Pharmacology | Reviews NMDA receptor antagonists memantine and ketamine as potential anti-migraine agents, synthesising PubMed/Embase/ClinicalTrials.gov evidence. |
| 17901918 | 2007 | Retrospective study (n=60) | Journal of Headache and Pain | Retrospective characterisation of memantine efficacy as preventive migraine therapy in a university headache clinic cohort. |
| 19031499 | 2008 | Open-label study | Headache | Assesses efficacy and tolerability of memantine for preventive treatment of refractory migraine. |
| 25159002 | 2014 | Review | The Annals of Pharmacotherapy | Describes current evidence evaluating efficacy and safety of memantine for prevention of primary headache disorders. |
Note: An additional commentary (PMID 34510445, “Memantine for migraine – Big promise but little evidence”, Headache 2021) directly cautions that despite the volume of positive-leaning publications, the underlying evidence base remains limited — this is reflected in the “Proceed with Guardrails” recommendation below.
UK Market Information
No marketing authorisation records are available in the current dataset. The evidence pack’s regulatory source records market status: Not Marketed, with 0 registered licences. This should be independently verified against the MHRA product database and BNF, as memantine is a well-established medicine in other markets; absence of a record here should not be interpreted as definitive UK non-availability.
Safety Considerations
Please refer to the SmPC and BNF for safety information. Report suspected adverse reactions via the Yellow Card Scheme.
(No structured warnings, contraindications, or drug interaction data were available in this evidence pack — flagged as a Blocking Data Gap, DG001.)
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: Migraine disorder is the only one of the four TxGNN-predicted indications for this drug with substantive supporting evidence (L1: one completed Phase 3 RCT, a network meta-analysis, a systematic review, and a decade-plus track record of case series/open-label studies). However, trial sample sizes are small (largest dedicated RCT n=33) and at least one published commentary explicitly questions whether the promise is matched by evidence quality. This combination — plausible mechanism, moderate trial volume, but underpowered confirmatory data — supports cautious, guarded progression rather than an unqualified Go.
The other three candidates (pulmonary hypertension, kyphoscoliotic heart disease, migraine with brainstem aura) remain at Hold: pulmonary hypertension and kyphoscoliotic heart disease have no relevant clinical trial evidence and only tangential or absent literature support (L5); migraine with brainstem aura has only indirect literature extrapolated from general migraine mechanism studies (L3).
To proceed, the following is needed:
- Resolution of the Blocking data gap on TFDA/MHRA-sourced warnings and contraindications (DG001) before any S1 safety review
- Confirmation of DrugBank/SmPC-sourced mechanism of action and original licensed indication (DG002)
- A larger, adequately powered confirmatory Phase 3 RCT for episodic migraine prophylaxis (current evidence base relies on small or open-label studies)
- Confirmation of actual UK/MHRA marketing authorisation status, given the “Not Marketed” flag in this dataset conflicts with memantine’s known international availability
- Further evidence collection (trials/mechanistic studies) before any decision-stage progression on pulmonary hypertension, kyphoscoliotic heart disease, or migraine with brainstem aura
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.