Dihexa for Migraine & Chronic Migraine: CGRP, BDNF, Hippocampal Atrophy, Atogepant (Aquipta) NICE TA973, Rimegepant, Eptinezumab & the 2026 UK Review

Approximately 10 million UK adults — roughly 1 in 7 Britons — live with migraine, around 1 million of them with chronic migraine (15 or more headache days per month for at least three months) on Migraine Trust and Brain Research UK 2026 figures. Migraine is more common than diabetes, epilepsy and asthma combined; women are affected approximately three times as often as men; it peaks during the most productive working years (30-50); and the UK economy loses an estimated 25-43 million workdays per year with annual costs of £6-10 billion in absenteeism and presenteeism. 2024-2026 has been the most consequential window for migraine in decades. On 15 May 2024 NICE issued Technology Appraisal TA973 recommending atogepant (Aquipta, AbbVie) 60mg once-daily oral CGRP receptor antagonist for the prevention of episodic and chronic migraine after three or more conventional preventatives have failed — making the UK the first European market with a NICE-approved oral CGRP gepant for prevention and bringing an estimated ~170,000 people in England into eligibility. TA919 (rimegepant acute) and TA906 (rimegepant prevention) complete the small-molecule CGRP antagonist pathway. The CGRP monoclonal antibody pathway is anchored by TA682 (erenumab / Aimovig), TA659 (galcanezumab / Emgality), TA764 (fremanezumab / Ajovy) and TA871 (eptinezumab / Vyepti). On the neurobiology side, the 2025 Cephalalgia review by Fernandes & Gil-Gouveia consolidated the network-dysfunction model of migraine-related cognitive dysfunction; the 2025 Medical Research Archives review on chronic migraine accelerated brain ageing and hippocampal atrophy formalised the neurodegenerative-trajectory hypothesis; the 2024 Hippocampal Connectivity Dynamics resting-state fMRI study showed hippocampal volume and connectivity predicting cognitive status; and the 2022 P2X7R/NLRP3 pyroptosis and neuroinflammation mouse model directly linked migraine-driven inflammasome activity to cognitive impairment. Against this backdrop, does Dihexa, the synaptogenic HGF/c-Met-activating peptide, have anything to offer the UK's 10 million migraine sufferers — or, given that serum BDNF is elevated rather than depleted in migraine (Tanure 2010), is a synaptogenic peptide directionally wrong for migraine biology? This rigorous 2026 UK review covers what is actually known, what is speculation, and where the evidence is genuinely absent. Readers may also want to read the closely related Dihexa for Fibromyalgia & Fibro Fog review (55% migraine comorbidity, same BDNF-elevated paradox), the Dihexa for Tinnitus review (the other ‘over-plastic circuit’ directionality problem), the Dihexa for Long COVID Brain Fog review (substantial migraine flare overlap), the Dihexa for Menopause Brain Fog review (perimenopausal migraine deterioration), the Dihexa for Anxiety & Chronic Stress review (migraine’s dominant psychiatric comorbidity), the Dihexa for Depression & Mood review (bidirectional comorbidity) and the Dihexa for Post-Stroke Recovery review (the migraine-with-aura cardiovascular axis).

Migraine in the UK in 2026: Scale, Definitions & Why It Matters

Migraine is the most prevalent of all chronic neurological disorders and consistently ranks among the World Health Organization's top three most disabling medical conditions on years-lived-with-disability (YLD) metrics. The Migraine Trust puts UK prevalence at approximately 10 million adults aged 15-69 — roughly 1 in 7 Britons — with around 1 million of those meeting the chronic migraine definition (15 or more headache days per month for at least three months, with at least eight days having migrainous features). Women are affected approximately three times as often as men; prevalence peaks in the 30-50 age window; and the UK experiences more than 190,000 migraine attacks every day. The economic and public-health cost is staggering: an estimated 25-43 million lost workdays per year in the UK and £6-10 billion in annual economic cost in absenteeism and presenteeism on PMC10552723 fiscal-framework analyses. The House of Commons Library 2024 research briefing on access to migraine treatment is the principal UK policy reference.

The diagnostic framework recognised in NICE NG150 (September 2021), the British Association for the Study of Headache (BASH) UK guideline and the International Classification of Headache Disorders, third edition (ICHD-3, 2018) defines:

• Migraine without aura (ICHD-3 1.1): ≥5 lifetime attacks of 4-72 hour duration, unilateral or bilateral, pulsating, moderate-to-severe, aggravated by routine physical activity, with nausea / vomiting or photophobia / phonophobia.
• Migraine with aura (1.2): one or more fully reversible focal neurological symptoms (visual, sensory, speech, motor, brainstem, retinal) developing gradually over 5-20 minutes, lasting <60 minutes.
• Chronic migraine (1.3): ≥15 headache days per month for ≥3 months, of which ≥8 have migrainous features.
• Hemiplegic migraine (1.2.3): aura including motor weakness. Familial forms map to CACNA1A (FHM1), ATP1A2 (FHM2) and SCN1A (FHM3).
• Vestibular migraine (1.6.5 / Lempert & Society Barany 2012 criteria): ≥5 vestibular episodes 5 min-72 h with current or prior migraine.
• Medication-overuse headache (MOH) (8.2): headache occurring on ≥15 days per month in a patient with pre-existing primary headache, in the context of regular over-use (≥10 days per month for triptans, ergots, opioids and combination analgesics; ≥15 days per month for simple analgesics) for >3 months.
• Cluster headache (3.1): trigeminal autonomic cephalalgia with strictly unilateral severe orbital / supraorbital pain, ipsilateral autonomic features and circadian / circannual clustering (~0.1% UK prevalence).

Severity and impact are quantified by HIT-6 (Headache Impact Test), MIDAS (Migraine Disability Assessment Scale) and the Migraine Trust’s MTIS-12. Genetic architecture is polygenic with notable Mendelian forms in familial hemiplegic migraine (FHM1 CACNA1A, FHM2 ATP1A2, FHM3 SCN1A) and CADASIL (NOTCH3) small-vessel disease. The MTHFR C677T polymorphism is overrepresented in migraine-with-aura cohorts. The BDNF Val66Met (rs6265) polymorphism has been associated with migraine susceptibility and treatment-response heterogeneity.

Comorbidity is the rule. Migraine demonstrates strong bidirectional comorbidity with: depression (relative risk ~2-4), anxiety and panic disorder, bipolar disorder, fibromyalgia (~55% comorbidity), irritable bowel syndrome (IBS), endometriosis, restless legs syndrome (RLS), obstructive sleep apnoea, ME/CFS, Long COVID, ADHD, hypermobile Ehlers-Danlos syndrome (hEDS) and mast cell activation syndrome (MCAS). Migraine-with-aura is an independent risk factor for ischaemic stroke (approximately 2× baseline; higher in young women on combined oral contraceptives), and a modest increase in dementia risk has been reported in women in Lancet Public Health migraine-and-dementia meta-analyses.

The Modern Mechanistic Picture: CSD, Trigeminovascular, CGRP, BDNF & Neuroinflammation

The dominant explanatory framework in 2026 is a cortical hyperexcitability → cortical spreading depression → trigeminovascular activation → CGRP release → neurogenic inflammation → central sensitisation cascade, layered on top of glutamatergic and serotonergic dysregulation, mitochondrial bioenergetic vulnerability, and an emerging neuroinflammation / glymphatic-dysfunction / gut-brain-axis story.

Cortical Spreading Depression (CSD)

First described by Leão in 1944, cortical spreading depression (CSD) is a slowly propagating wave of neuronal and glial depolarisation moving across the cortex at ~3 mm/min, followed by sustained suppression of cortical activity. CSD is now firmly established as the electrophysiological substrate of migraine aura in humans on the basis of BOLD fMRI, MEG and intracortical recording data, and is thought to drive trigeminovascular activation through cortically-released potassium, nitric oxide and arachidonic-acid metabolites that sensitise meningeal nociceptors. Topiramate, sodium valproate, lamotrigine and propranolol all raise CSD threshold in animal models.

The Trigeminovascular System

The trigeminovascular hypothesis (Moskowitz, Goadsby, Edvinsson) frames migraine pain as arising from activation and sensitisation of nociceptive fibres innervating cranial blood vessels and dura mater, their cell bodies in the trigeminal ganglion, and their central projections to the trigeminal nucleus caudalis and the thalamus. Activation triggers release of vasoactive and pro-inflammatory neuropeptides — principally calcitonin gene-related peptide (CGRP), pituitary adenylate cyclase-activating polypeptide (PACAP-38), substance P and neurokinin A — producing the “neurogenic inflammation” that the entire CGRP-targeting therapeutic class is designed to interrupt.

CGRP — The Therapeutic Centrepiece of 2024-2026

CGRP is a 37-amino-acid neuropeptide with potent cerebrovascular vasodilator and pro-inflammatory activity; trigeminal-ganglion CGRP levels rise during attacks and CGRP infusion reliably triggers migraine in susceptible individuals. The therapeutic class targeting CGRP has transformed UK migraine care: small-molecule CGRP-receptor antagonists (gepants: atogepant, rimegepant, ubrogepant, zavegepant) and monoclonal antibodies against CGRP-ligand (galcanezumab, fremanezumab, eptinezumab) or CGRP-receptor (erenumab). See the NICE TA973 atogepant guidance and the British Journal of General Practice 2024 CGRP-in-primary-care review.

Glutamatergic Hyperexcitability

Migraine is genetically and physiologically a disorder of cortical hyperexcitability. CACNA1A (FHM1) mutations enhance presynaptic glutamate release; ATP1A2 (FHM2) and SCN1A (FHM3) mutations impair potassium / sodium homeostasis driving similar hyperexcitability. CSF glutamate is elevated in migraine. The therapeutic success of topiramate, sodium valproate and lamotrigine in migraine prevention is largely attributable to glutamate-stabilisation / GABA-enhancement.

Neuroinflammation, the NLRP3 Inflammasome & Glymphatic Dysfunction

Recent work has shifted the emphasis toward chronic neuroinflammation as a driver of migraine chronification and cognitive dysfunction. The 2022 P2X7R/NLRP3 signalling pathway-mediated pyroptosis and neuroinflammation contributed to cognitive impairment in a mouse model of migraine paper (PMC9250730) showed that purinergic P2X7 receptor activation drives NLRP3 inflammasome assembly, gasdermin-mediated pyroptosis, IL-1β release and downstream cognitive impairment. Glymphatic-system dysfunction (impaired CSF-mediated clearance of metabolic waste from the brain interstitium during sleep) is the second emerging mechanism. Gut microbiota dysbiosis is the third.

BDNF in Migraine — The Directionality Problem

Brain-derived neurotrophic factor (BDNF) in migraine sits in an awkward place for any synaptogenic-peptide claim. The Tanure 2010 Headache pilot study showed serum BDNF rises significantly during migraine attacks, with several subsequent studies replicating an inter-ictal elevation pattern (although a minority of studies report low or normal BDNF). BDNF is mechanistically positioned as a facilitator of central sensitisation in trigeminal nucleus caudalis and thalamic projection neurons, and is implicated in chronic pain and central sensitisation more broadly — see the 2023 BDNF-as-neuropathic-pain-biomarker review (PMC10013954). This creates the central directionality paradox for any synaptogenic peptide claim in migraine: a peptide whose principal downstream action is BDNF/TrkB augmentation is pushing the same lever that already appears to be over-active in migraine biology — the same problem that arises in our fibromyalgia review.

2025: Chronic Migraine, Hippocampal Atrophy & Accelerated Brain Ageing

The most consequential 2025 paper for the Dihexa-migraine question is the Medical Research Archives review on chronic migraine and accelerated brain ageing focused on hippocampal atrophy. The thesis: chronic migraine is associated with persistent neuroinflammation, white-matter alterations, cortical thinning and hippocampal atrophy that together constitute an accelerated-brain-ageing trajectory. Cognitive dysfunction follows: declarative memory difficulties, memory-encoding disruption, higher rates of depression and anxiety. The 2024 Hippocampal Connectivity Dynamics and Volumetric Alterations Predict Cognitive Status in Migraine resting-state fMRI study (PMID 39675538) reported altered hippocampal connectivity and volume predicting cognitive status. The 2023 Frontiers in Aging Neuroscience paper on shared alterations in hippocampal structural covariance in subjective cognitive decline and migraine mapped the structural similarity. The 2025 Fernandes & Gil-Gouveia Cephalalgia review framed the cognitive dysfunction across prefrontal cortex, thalamus, hypothalamus, hippocampus and cerebellum, modulated by serotonin and dopamine systems. This neurodegenerative-trajectory framing is the one place where a synaptogenic neuroprotective peptide has a coherent theoretical home in migraine biology — not as acute or prophylactic treatment, but as cognitive-rehabilitation adjunct in established chronic migraine.

The 2026 UK Treatment Landscape: NICE NG150, Acute Treatment, Prevention & the CGRP Revolution

UK migraine management is anchored by NICE NG150 (September 2021) and the BASH (British Association for the Study of Headache) UK guideline. Care is stratified into acute attack treatment, preventive treatment, chronic migraine-specific options, and the CGRP pathway for refractory cases.

Acute Attack Treatment

• First-line simple analgesia: NSAIDs (ibuprofen 400-600mg, naproxen 250-500mg, aspirin 900mg, diclofenac 50mg) or paracetamol 1g, ideally taken at attack onset.
• Triptans (5-HT_1B/1D agonists): sumatriptan 50-100mg orally or 6mg subcutaneous; rizatriptan 10mg (avoid in propranolol co-prescription, dose-adjust); eletriptan 40-80mg; zolmitriptan 2.5-5mg (also nasal); naratriptan 2.5mg; frovatriptan 2.5mg; almotriptan 12.5mg. Contraindicated in ischaemic heart disease, uncontrolled hypertension, hemiplegic / basilar migraine.
• Gepants for acute treatment: rimegepant (Nurtec ODT / Vydura) 75mg orally disintegrating under NICE TA919; ubrogepant (Ubrelvy, AbbVie) 50/100mg orally; zavegepant (Zavzpret, Pfizer) 10mg intranasal spray.
• Ditans: lasmiditan (Reyvow, Eli Lilly) 50-200mg orally — 5-HT_1F agonist with no vasoconstrictor activity; appropriate where triptans are contraindicated.
• Antiemetic: metoclopramide 10mg or domperidone 10mg orally / IM / IV.
• Avoid: codeine and other opioids (rebound, MOH risk); routine combination analgesics in chronic migraine.

Conventional Oral Preventatives

Started when migraine is significantly impacting quality of life or attack frequency is ≥4 migraine days per month. NICE-recommended preventatives:

• Propranolol 80-240mg daily — first-line non-pregnant.
• Amitriptyline 10-75mg at night (off-label) — particularly useful in tension-type comorbidity, sleep disturbance, depression comorbidity.
• Topiramate 50-100mg daily — effective but with cognitive side effects (paraesthesia, word-finding difficulty, weight loss); teratogenic.
• Candesartan 16mg daily (off-label).
• Sodium valproate — effective but contraindicated in women of childbearing potential except under the MHRA Pregnancy Prevention Programme following 2024-2025 MHRA tightening. See the MHRA Drug Safety Update Annex IV.
• Other / specialist: pizotifen; flunarizine; verapamil (cluster headache prevention); methysergide (rarely used).

Chronic Migraine: OnabotulinumtoxinA (Botox) under NICE TA260

For chronic migraine (≥15 headache days per month for ≥3 months) that has not responded to 3 oral preventatives, NICE recommends onabotulinumtoxinA (Botox) under TA260 using the PREEMPT protocol — 155 units administered across 31 fixed-site injections in seven head and neck muscle areas, every 12 weeks. PREEMPT phase 3 trials demonstrated a ~9-day-per-month reduction in headache days. Continuation requires a ≥30% reduction in headache days at the 12-week reassessment.

The CGRP Pathway — The 2024-2026 UK Revolution

NICE has now recommended six CGRP-pathway therapies, all gated on failure of at least 3 oral preventatives (4 in chronic migraine on top of onabotulinumtoxinA). The full UK CGRP pathway as of May 2026:

Continuation criteria are tight: stop after 12 weeks if migraine days have not reduced by ≥50% in episodic migraine or ≥30% in chronic migraine. Atogepant’s once-daily oral administration distinguishes it from the injectable monoclonals; The Conversation 2024 explainer and Medicines Team UK 2024 summary provide patient-facing overviews. The 2025 PMC12678924 gepants review and PMC12818195 CGRP real-world insights consolidate the evidence base.

Neuromodulation & Devices

Three external neuromodulation devices have UK and FDA evidence: GammaCore (electroCore) non-invasive vagus nerve stimulator (nVNS) — acute and preventive for migraine and cluster headache; Cefaly external trigeminal nerve stimulator — supraorbital, acute and preventive; Nerivio (Theranica) remote electrical neuromodulation armband for acute use. None replace pharmacological treatment but offer drug-sparing options, particularly in pregnancy and lactation.

Patent Foramen Ovale (PFO) Closure — The Persisting Controversy

Despite enthusiastic uptake by some private cardiologists, the four randomised trials of PFO closure for migraine prevention (MIST, PRIMA, PREMIUM, CLOSURE-3) have failed to demonstrate clear prophylactic benefit over medical therapy on primary endpoints, although post-hoc and subgroup analyses have shown signals in migraine-with-aura phenotypes. The current UK consensus is that PFO closure should not be performed for migraine alone, although it may be appropriate for combined indications (cryptogenic stroke + migraine-with-aura + appropriate-risk PFO).

Migraine Brain Fog, Cognitive Dysfunction & Accelerated Brain Ageing

Migraine-related cognitive dysfunction has only recently moved from clinical anecdote to formal evidence base. The 2025 Fernandes & Gil-Gouveia review in Cephalalgia identifies four temporally distinct cognitive-dysfunction phases: (1) prodromal — reduced concentration, mental sluggishness 24-48 hours before pain onset; (2) aura — transient focal cognitive deficits during the aura phase (typically visual / language); (3) ictal — attention, working memory, processing speed and executive function deficits during the headache phase; (4) postdrome — “migraine hangover” cognitive slowing for hours to a day after pain resolves.

The 2025 hippocampal-atrophy and accelerated-brain-ageing literature (Medical Research Archives 2025; ESM migraine cognitive impairment review) adds an inter-ictal chronic-impairment layer in chronic migraine specifically — cortical thinning, hippocampal atrophy, declarative memory difficulty, encoding disruption, higher rates of depression and anxiety. The Progress in Mind Canada review of brain fog in migraine ties together the clinical phenomenology. The leading mechanistic hypotheses are chronic neuroinflammation (P2X7R/NLRP3 inflammasome, IL-1β, IL-6, TNF-α), glymphatic dysfunction (impaired CSF clearance of metabolic waste during sleep) and gut-brain-axis dysbiosis. The historic CAMERA-1 and CAMERA-2 studies showed migraine-with-aura confers a modestly increased white-matter-hyperintensity burden on MRI.

For Dihexa biology, this is the one place where a synaptogenic neuroprotective peptide has a coherent theoretical home in migraine — not as acute or prophylactic treatment, but as cognitive-rehabilitation adjunct in established chronic migraine with documented hippocampal-volume loss and persistent inter-ictal cognitive impairment. This frame is hypothetical: no animal model of Dihexa-in-chronic-migraine-recovery has been published, no Phase 1 work in any chronic-pain population, no fosgonimeton parallel.

Where Could Dihexa Theoretically Fit in Migraine Biology?

The honest mechanistic mapping is mixed. Dihexa (PNB-0408), on the Benoist 2014 JPET evidence base, acts as a positive allosteric modulator of the hepatocyte growth factor (HGF) / c-Met system, with downstream effects on BDNF/TrkB signalling, dendritic spine formation, synaptogenesis and cerebrovascular angiogenesis. Wright & Harding (2015) reviewed the brain HGF/c-Met system as a therapeutic target. The closest clinical analogue, fosgonimeton (ATH-1017), has failed two Phase 3 Alzheimer's trials (LIFT-AD) and has never been tested in any migraine or headache population.

The summary: of the seven major migraine-pathology axes, Dihexa biology is plausibly relevant only to the chronic-migraine hippocampal-atrophy / cognitive-recovery axis — and directionally problematic for the cortical hyperexcitability, central sensitisation and BDNF-elevation axes that drive the primary pathology. This is roughly the inverse of the case for Alzheimer's disease, where Dihexa biology is congruent with the dominant pathology.

The One Plausible Frame: Chronic-Migraine Cognitive Rehabilitation

If a hypothetical future Dihexa migraine trial were ever to be designed, the defensible frame would be: chronic migraine patients with established structural evidence of hippocampal volume loss on MRI (per the 2024 Hippocampal Connectivity Dynamics paper), already on optimised conventional and CGRP-pathway prevention, with persistent inter-ictal cognitive impairment (HIT-6 cognitive subscale, MoCA, processing-speed measures). The hypothesis would be neuroprotective cognitive recovery rather than migraine-frequency reduction. The trial design would have to monitor for paradoxical CSD-threshold lowering / attack-frequency increase as a stopping criterion. This entire frame is hypothetical: no preclinical Dihexa-in-chronic-migraine model has been published, no Phase 1 in any chronic-pain population, and fosgonimeton's LIFT-AD Phase 3 failure substantially weakens the HGF/c-Met-translates-to-clinical-cognition story.

Risks & Theoretical Concerns Specific to Migraine

Beyond the generic risks in the Dihexa side-effects review, migraine-specific concerns include:

• CSD threshold lowering / attack-frequency increase: the core directionality risk — a glutamatergic synaptogenic peptide could plausibly worsen migraine frequency, particularly in migraine-with-aura.
• Central sensitisation consolidation: the trigeminal nucleus caudalis / thalamic sensitisation that drives allodynia, photophobia and chronification could be reinforced rather than relieved — the same problem as in fibromyalgia and tinnitus.
• BDNF directionality paradox: serum BDNF is already elevated in attacks (Tanure 2010); pushing further the same direction is mechanistically uncomfortable.
• Hemiplegic migraine specifically: CACNA1A / ATP1A2 / SCN1A mutations already produce hyperexcitability; a synaptogenic peptide is contraindicated in concept.
• Migraine-with-aura cardiovascular risk: independent stroke risk factor (relative risk ~2×); any peptide with vasoactive potential warrants particular caution.
• SSRI / triptan co-prescription: theoretical serotonin-syndrome risk and FDA 2006 warning on SSRI + triptan combinations remain context for any neuroactive co-administration.
• Medication-overuse headache pattern: any non-evidence-based agent used regularly risks adding to the MOH burden in the chronic-migraine population.
• Pregnancy / women of childbearing potential: migraine peaks in this demographic; no peptide reproductive-toxicology data; the MHRA Pregnancy Prevention Programme experience with sodium valproate is the contextual warning.
• c-Met oncogenicity: chronic c-Met activation is a known oncogenic pathway in multiple cancers; particularly relevant in the long-exposure migraine demographic.
• Comorbid bipolar disorder: manic-switch concerns from our bipolar review apply.

UK Resources, Charities & Specialist Services for Migraine

National charities & patient organisations: The Migraine Trust (UK’s leading migraine charity; helpline, peer support, advocacy); National Migraine Centre (specialist London-based charity clinic); Brain Research UK (research funding); OUCH UK (Organisation for the Understanding of Cluster Headache); Hemiplegic Migraine Association UK; British Association for the Study of Headache (BASH); Headache UK (Alliance of Headache Disorders Organisations).

NHS pathway: GP-led primary-care management under NICE NG150; referral to neurology / headache specialist for the CGRP pathway after 3+ preventative failures (4+ in chronic migraine on top of onabotulinumtoxinA); tertiary headache services at the National Hospital for Neurology and Neurosurgery (Queen Square, UCLH), the Walton Centre Liverpool, Hurstwood Park Newcastle, and the Princess Margaret Hospital Swindon.

Research & professional bodies: NIHR Be Part of Research (open UK migraine trials); Migraine Science Collaborative; the International Headache Society (IHS) ICHD-3 reference; Royal College of Physicians; Association of British Neurologists (ABN).

The 2026 Bottom Line

Migraine is the condition for which the UK’s 2024-2026 NICE pipeline has produced the most coherent and evidence-based new treatment pathway of any field covered in this site — and the one where a research peptide with no human data has the least to add. The May 2024 NICE TA973 atogepant approval, the rimegepant TA919/TA906 dual indication, the four CGRP monoclonal antibody NICE pathways (TA659, TA682, TA764, TA871), the established TA260 onabotulinumtoxinA for chronic migraine, and the conventional preventative armamentarium (propranolol, amitriptyline, topiramate, candesartan) together provide a structured, NICE-funded, NHS-accessible pathway for the vast majority of the UK’s 10 million migraine sufferers. The 2025 hippocampal-atrophy / accelerated-brain-ageing literature opens a legitimate cognitive-recovery research direction — but the Tanure 2010 BDNF-elevation paradox, the CSD-threshold concerns, and the central-sensitisation consolidation risk all point to a directionally wrong fit for any synaptogenic peptide in migraine biology, with the partial exception of the chronic-migraine cognitive-rehabilitation niche. No clinical trial of Dihexa in any migraine population has been conducted, registered or planned. Fosgonimeton (ATH-1017) — the closest HGF-pathway molecule with human data — has never been tested in migraine. The evidence-based 2026 UK pathway is GP-led NICE NG150 management with timely neurology referral for the CGRP pathway. The Migraine Trust and the National Migraine Centre are the principal patient-facing navigation resources. The 2024-2026 NICE migraine pipeline is the case study of how a genuine therapeutic revolution displaces speculative peptide claims.

Selected References & External Sources

1. NICE TA973 (15 May 2024). Atogepant for preventing migraine. — nice.org.uk/guidance/ta973 · Recommendations · Information for the public
2. NICE press release (May 2024). 170,000 people in England to access atogepant. — nice.org.uk press release
3. NICE NG150 (Sep 2021). Headaches in over 12s: diagnosis and management. — nice.org.uk/guidance/ng150
4. NICE TA260 (2012). OnabotulinumtoxinA for chronic migraine. — nice.org.uk/guidance/ta260
5. CGRP pathway NICE TAs — TA919 rimegepant acute · TA906 rimegepant prevention · TA659 galcanezumab · TA682 erenumab · TA764 fremanezumab · TA871 eptinezumab
6. BJGP (Sep 2024). CGRP therapy in primary care for migraine: prevention and acute medication. — bjgp.org/content/74/748/521
7. Fernandes C, Gil-Gouveia R (2025). Pathophysiology of migraine-related cognitive dysfunction. Cephalalgia. — SAGE
8. Chronic Migraine and Accelerated Brain Ageing: Hippocampal Atrophy (2025). Med Res Arch. — ESM MRA · ESM summary
9. P2X7R/NLRP3 pyroptosis & neuroinflammation in migraine cognitive impairment mouse model (2022). — PMC9250730
10. Hippocampal Connectivity Dynamics & Volumetric Alterations in Migraine (2024). — PubMed 39675538
11. Shared hippocampal structural covariance in SCD & migraine (2023). Front Aging Neurosci. — Frontiers
12. Tanure MT et al. (2010). Increased serum BDNF during migraine attacks. Headache. — PubMed 20556464
13. BDNF as biomarker for neuropathic pain (2023). — PMC10013954
14. Association between migraine and cognitive impairment (review). — PMC9317452
15. The Migraine Trust. — migrainetrust.org · State of the Migraine Nation. — Impact review (PDF)
16. National Migraine Centre. — nationalmigrainecentre.org.uk
17. Brain Research UK. — brainresearchuk.org.uk
18. House of Commons Library (2024). Access to migraine treatment. — commonslibrary.parliament.uk
19. The Hidden Economic Consequences of Migraine to the UK Government (2023). — PMC10552723
20. The cost of migraine to the NHS in England: retrospective cohort using CPRD & HES. — T&F 2025
21. Gepants review (2025). — PMC12678924 · CGRP real-world insights (2025). — PMC12818195
22. Atogepant Phase 3 review (2023). — PMC10411686
23. The Conversation (2024). Atogepant explainer. — theconversation.com
24. iatroX. NICE migraine guidance + red flags (2026). — iatrox.com
25. Migraine Science Collaborative. January 2026 clinical research update. — migrainecollaborative.org
26. Benoist CC et al. (2014). HGF/c-Met dependence of Dihexa. JPET. — PubMed 24403718 · Wright & Harding (2015). Brain HGF/c-Met. — PubMed 25711386
27. British Association for the Study of Headache (BASH). — bash.org.uk · International Headache Society. — ihs-headache.org
28. OUCH UK (cluster headache). — ouch.org.uk · Hemiplegic Migraine Association UK. — hemiplegic-migraine.org