Memantine

證據等級: L5

預測適應症: 10 個

Memantine: From Alzheimer’s Disease to Migraine Disorder

One-Sentence Summary

Memantine is an NMDA receptor antagonist originally used to treat moderate-to-severe Alzheimer’s disease. Among the candidates in this evidence pack, migraine disorder is the best-supported repurposing direction, backed by 1 completed Phase 3 RCT and 20 publications, including two systematic reviews/meta-analyses. A separate TxGNN top-ranked candidate, pulmonary hypertension, is noted below but rests on much weaker, largely indirect evidence.

Quick Overview

Item	Content
Original Indication	Alzheimer’s disease (dementia) — general public knowledge; not captured in this evidence pack’s regulatory data
Predicted New Indication	Migraine disorder
TxGNN Prediction Score	99.52% (rank 5756 of all drug–disease pairs)
Evidence Level	L2
Australia Market Status	Not marketed
Number of ARTG Entries	0
Recommended Decision	Hold

Note on TxGNN’s top-ranked candidate: TxGNN’s single highest-scoring prediction for memantine was actually pulmonary hypertension (99.54%, rank 5636), not migraine. However, the supporting evidence for this candidate is thin (L3, no clinical trials of memantine itself) and largely concerns MN-08, a nitrate-ester derivative of memantine currently in Phase 1 human trials for pulmonary arterial hypertension — not memantine itself. Because efficacy data for a derivative cannot be directly attributed to the parent drug, this report focuses on migraine disorder, where the evidence is both stronger and specific to memantine.

Why is This Prediction Reasonable?

Detailed mechanism-of-action data is not available in this evidence pack (data gap). Based on publicly available information, memantine is a non-competitive NMDA receptor antagonist, a drug class whose efficacy in moderate-to-severe Alzheimer’s disease is well established. Mechanistically, this class may plausibly extend to migraine disorder.

Glutamate/NMDA receptor signalling is implicated in two core mechanisms of migraine pathophysiology: cortical spreading depression and sensitisation of the trigeminovascular system. Because memantine already crosses the blood-brain barrier and blunts excessive NMDA-mediated excitatory signalling in the CNS for its approved dementia indication, the same pharmacology offers a direct, testable rationale for migraine prophylaxis — distinct from most repurposing candidates, which rely on more speculative mechanistic bridges.

This rationale is reinforced by an unusually long track record of clinical investigation specific to memantine (not a derivative): open-label case series from as early as 2007–2009, a placebo-controlled RCT in 2016, and a head-to-head Phase 3 trial against sodium valproate completed in 2020, followed by systematic reviews and meta-analyses through 2025. That said, one 2021 commentary explicitly frames this as “big promise but little evidence,” and a contemporaneous meta-analysis describes memantine’s migraine efficacy as “controversial” — so the evidence base, while long-standing, remains mixed rather than conclusive.

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; direct drug-indication match, but small sample size limits statistical power.
NCT02670161	Phase 4	Enrolling by invitation	3300	EMR-based pragmatic registry spanning 10 common neurological disorders at NorthShore University HealthSystem; not a dedicated memantine-migraine interventional trial, so relevance is low.

No ANZCTR-registered trials were identified for this indication in the evidence pack.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
39467289	2024	Clinical Practice Guideline	Ann Intern Med	2023 US VA/DoD guideline covering treatment and prevention recommendations for migraine and tension-type headache.
33961371	2021	Meta-analysis of RCTs	Clin Neuropharmacol	Pooled analysis of randomised trials comparing memantine with placebo for migraine; concludes efficacy remains controversial.
34352118	2021	Systematic Review	Headache	Assesses efficacy and safety of memantine specifically for prophylactic treatment of episodic migraine.
26638119	2016	RCT	Headache	Randomised, double-blind, placebo-controlled trial of memantine for prophylaxis of migraine without aura.
40978493	2025	Network Meta-analysis	Front Pharmacol	Compares efficacy and safety of oral preventive migraine medications, including memantine, in adults aged 18–65.
36869904	2023	Review	Naunyn Schmiedebergs Arch Pharmacol	Reviews NMDA receptor antagonists memantine and ketamine as candidate anti-migraine agents.
34048395	2021	Review	Continuum (Minneap Minn)	General overview of preventive migraine treatment options, including older oral agents and CGRP-targeted therapies.
34510445	2021	Commentary	Headache	Editorial commentary, “Memantine for migraine — big promise but little evidence.”
19280698	2009	Open-label cohort	Headache	Early clinical experience using memantine for preventive treatment of migraine and refractory migraine.
17901918	2007	Retrospective case series	J Headache Pain	Retrospective review of 60 patients treated with memantine as migraine preventive therapy in a university headache clinic.

Australia Market Information

Memantine currently has no ARTG entries and is not marketed in Australia according to this evidence pack. No product, dosage form, or approved-indication data is available to tabulate.

Safety Considerations

Please refer to the TGA-approved Product Information (PI) for safety information. This evidence pack could not retrieve TFDA/TGA label warnings, contraindications, or drug-interaction data for memantine (flagged as a blocking data gap — see Conclusion below), so no safety details can be reported here beyond that gap itself.

Conclusion and Next Steps

Decision: Hold

Rationale: Migraine disorder has a genuinely encouraging, memantine-specific evidence base (a completed Phase 3 RCT, an earlier placebo-controlled RCT, a systematic review, and multiple meta-analyses spanning nearly two decades of clinical use). However, the evidence itself is explicitly described in the literature as mixed/controversial, and — critically — this evidence pack has a blocking data gap on TGA-approved warnings and contraindications, meaning a safety assessment (S1) cannot be completed. Memantine is also not currently registered in Australia (0 ARTG entries), so there is no existing local label to lean on.

To proceed, the following is needed:

TGA-approved Product Information (or equivalent overseas label) to close the blocking safety data gap (DG001) before any S1 safety review can begin
Confirmed mechanism-of-action data from DrugBank (DG002) to substantiate the mechanistic rationale beyond public-domain knowledge
Clarification of an ARTG registration pathway, since memantine is not currently marketed in Australia under any indication
A dedicated review of whether the mixed/controversial efficacy signal in the migraine literature (per PMID 33961371 and 34510445) meets the bar for further investment, ideally via an updated meta-analysis or a new adequately powered RCT
Disclaimer

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