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Objective: To estimate the number needed to treat and cost per additional responder for atogepant and rimegepant versus placebo for the preventive treatment of episodic migraine (EM) in the United States. Background: Migraine has an enormous impact on a person's daily activities and quality of life, and results in significant clinical and economic burden to both individuals and society. It is important to understand the comparative efficacy and economic value of oral calcitonin gene–related peptide receptor antagonists (gepants) for preventive treatment of EM. Currently, atogepant and rimegepant are US Food and Drug Administration approved for preventive treatment of migraine (rimegepant for EM and atogepant for EM and for chronic migraine). In the absence of head‐to‐head trials, we utilized an indirect treatment comparison on efficacy data from clinical trials conducted for the preventive treatment of EM. We estimated number needed to treat, a valuable metric used in clinical practice to compare treatment efficacy, and cost per additional responder, which can be used to establish the cost effectiveness of a treatment. Methods: An indirect treatment comparison was conducted to compare the efficacy of atogepant 60 mg once daily and rimegepant 75 mg once every other day as preventive treatments for EM using published data from the registrational trials of atogepant (ADVANCE) and rimegepant (BHV3000‐305). The efficacy outcome of interest was ≥50% reduction from baseline in mean monthly migraine/headache days (≥50% responder rate), which was variably defined for a base case and two scenario analyses. Number needed to treat and cost per additional responder versus placebo were calculated and compared between both treatments (weeks 9–12 in the base case analysis; weeks 1–12 and 9–12 for atogepant and during weeks 9–12 for rimegepant in the scenario analyses). Results: In the base case analysis, ≥50% responder rates were 64.9% (95% confidence interval [CI], 53.9–74.5) for atogepant and 51.8% (95% CI, 42.9–60.6) for rimegepant, compared to 44.1% (95% CI, 39.4–49.0) for placebo. The median number needed to treat versus placebo in the base case scenario was 4.8 (95% CI, 3.1–9.0) for atogepant compared to 13.0 (95% CI, 5.9–75.1) for rimegepant. The cost per additional responder versus placebo in the base case scenario was estimated to be $15,823 (95% CI, $11,079–$29,516) for atogepant compared to $73,029 (95% CI, $32,901–$422,104) for rimegepant. Results of the two scenario analyses were consistent with the base case analysis. Conclusions: Atogepant had substantially lower numbers needed to treat and costs per additional responder versus placebo than rimegepant for the preventive treatment of EM across all evaluated scenarios. These analyses suggest that atogepant may be more cost effective than rimegepant for the preventive treatment of EM. Limitations include differences in inclusion/exclusion criteria and in reporting of the ≥50% responder rates between trials. Plain Language Summary: No trials have directly compared atogepant to rimegepant for prevention of episodic migraine, so we used data from published clinical trials to conduct an indirect treatment comparison of these two medicines, estimate the number of patients needed to achieve at least a 50% migraine day reduction, and determine the cost of treatment per additional responder. Our results suggested that 5 patients would need to be treated with atogepant to achieve at least a 50% migraine day reduction, compared to 13 with rimegepant. We also estimated that treatment with rimegepant would cost approximately $60,000 more than treatment with atogepant to achieve a ≥50% reduction in migraine days for one patient. [ABSTRACT FROM AUTHOR]

Recently, we showed that while atogepant—a small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist—does not fully prevent activation of meningeal nociceptors, it significantly reduces a cortical spreading depression (CSD)-induced early response probability in C fibres and late response probability in Aδ fibres. The current study investigates atogepant effect on CSD-induced activation and sensitization of high threshold (HT) and wide dynamic range (WDR) central dura-sensitive trigeminovascular neurons. In anaesthetized male rats, single-unit recordings were used to assess effects of atogepant (5 mg/kg) versus vehicle on CSD-induced activation and sensitization of HT and WDR trigeminovascular neurons. Single cell analysis of atogepant pretreatment effects on CSD-induced activation and sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus revealed the ability of this small molecule CGRP receptor antagonist to prevent activation and sensitization of nearly all HT neurons (8/10 versus 1/10 activated neurons in the control versus treated groups, P = 0.005). In contrast, atogepant pretreatment effects on CSD-induced activation and sensitization of WDR neurons revealed an overall inability to prevent their activation (7/10 versus 5/10 activated neurons in the control versus treated groups, P = 0.64). Unexpectedly however, in spite of atogepant's inability to prevent activation of WDR neurons, it prevented their sensitization (as reflected their responses to mechanical stimulation of the facial receptive field before and after the CSD). Atogepant' ability to prevent activation and sensitization of HT neurons is attributed to its preferential inhibitory effects on thinly myelinated Aδ fibres. Atogepant's inability to prevent activation of WDR neurons is attributed to its lesser inhibitory effects on the unmyelinated C fibres. Molecular and physiological processes that govern neuronal activation versus sensitization can explain how reduction in CGRP-mediated slow but not glutamate-mediated fast synaptic transmission between central branches of meningeal nociceptors and nociceptive neurons in the spinal trigeminal nucleus can prevent their sensitization but not activation. [ABSTRACT FROM AUTHOR]

Objective: To analyze data from the Chronic Migraine Epidemiology and Outcomes‐International (CaMEO‐I) Study in order to characterize preventive medication use and identify preventive usage gaps among people with migraine across multiple countries. Background: Guidelines for the preventive treatment of migraine are available from scientific organizations in various countries. Although these guidelines differ among countries, eligibility for preventive treatment is generally based on monthly headache day (MHD) frequency and associated disability. The overwhelming majority of people with migraine who are eligible for preventive treatment do not receive it. Methods: The CaMEO‐I Study was a cross‐sectional, observational, web‐based panel survey study performed in six countries: Canada, France, Germany, Japan, the United Kingdom, and the United States. People were invited to complete an online survey in their national language(s) to identify those with migraine according to modified International Classification of Headache Disorders, 3rd edition, criteria. People classified with migraine answered questions about current and ever use of both acute and preventive treatments for migraine. Available preventive medications for migraine differed by country. MHD frequency and associated disability data were collected. The American Headache Society (AHS) 2021 Consensus Statement algorithm was used to determine candidacy for preventive treatment (i.e., ≥3 monthly MHDs with severe disability, ≥4 MHDs with some disability, or ≥6 MHDs regardless of level of disability). Results: Among 90,613 valid completers of the screening survey, 14,492 met criteria for migraine and completed the full survey, with approximately 2400 respondents from each country. Based on the AHS consensus statement preventive treatment candidacy algorithm, averaging across countries, 36.2% (5246/14,492) of respondents with migraine qualified for preventive treatment. Most respondents (84.5% [4431/5246]) who met criteria for preventive treatment according to the AHS consensus statement were not using a preventive medication at the time of the survey. Moreover, 19.3% (2799/14,492) of respondents had ever used preventive medication (ever users); 58.1% (1625/2799) of respondents who reported ever using a preventive medication for migraine were still taking it. Of the respondents who were currently using a preventive medication, 50.2% (815/1625) still met the criteria for needing preventive treatment based on the AHS consensus statement. Conclusions: Most people with migraine who qualify for preventive treatment are not currently taking it. Additionally, many people currently taking preventive pharmacologic treatment still meet the algorithm criteria for needing preventive treatment, suggesting inadequate benefit from their current regimen. Plain Language Summary: People with migraine who experience frequent headaches or some level of disability may benefit from using a preventive medication for migraine. We collected data on the use of preventive medication for migraine in Canada, France, Germany, Japan, the United Kingdom, and the United States. These data demonstrated that many people who qualified for the use of a preventive treatment in the six participating countries were not currently taking a preventive medication for migraine. [ABSTRACT FROM AUTHOR]

Objective: To characterize the direct impact of monthly headache days (MHDs) on health‐related quality of life (HRQoL) in people with migraine and the potential mediating effects of anxiety, depression, and allodynia. Background: Although the general relationship between increased migraine frequency (i.e., MHDs) and reduced HRQoL is well established, the degree to which reduced HRQoL is due to a direct effect of increased MHDs or attributable to mediating factors remains uncertain. Methods: Cross‐sectional baseline data from participants with migraine who completed the Core and Comorbidities/Endophenotypes modules in the 2012–2013 US Chronic Migraine Epidemiology and Outcomes (CaMEO) study, a longitudinal web‐based survey study, were analyzed. The potential contribution of depression, anxiety, and/or allodynia to the observed effects of MHDs on HRQoL as measured by the Migraine‐Specific Quality‐of‐Life Questionnaire version 2.1 (MSQ) was evaluated. Results: A total of 12,715 respondents were included in the analyses. The MSQ domain scores demonstrated progressive declines with increasing MHD categories (B = −1.23 to −0.60; p < 0.001). The observed HRQoL decrements associated with increasing MHDs were partially mediated by the presence of depression, anxiety, and allodynia. The MHD values predicted 24.0%–32.4% of the observed variation in the MSQ domains. Depression mediated 15.2%–24.3%, allodynia mediated 9.6%–16.1%, and anxiety mediated 2.3%–6.0% of the observed MHD effects on the MSQ. Conclusions: Increased MHD values were associated with lower MSQ scores; the impact of MHDs on the MSQ domain scores was partially mediated by the presence of depression, anxiety, and allodynia. MHDs remain the predominant driver of the MSQ variation; moreover, most of the variation in the MSQ remains unexplained by the variables we analyzed. Future longitudinal analyses and studies may help clarify the contribution of MHDs, comorbidities, and other factors to changes in HRQoL. [ABSTRACT FROM AUTHOR]

Background: OnabotulinumtoxinA (onabotA), is assumed to achieve its therapeutic effect in migraine through blocking activation of unmyelinated meningeal nociceptors and their downstream communications with central dura-sensitive trigeminovascular neurons in the spinal trigeminal nucleus (SPV). The present study investigated the mechanism of action of onabotA by assessing its effect on activation and sensitization of dura-sensitive neurons in the SPV by cortical spreading depression (CSD). It is a follow up to our recent study on onabotA effects on activation and sensitization of peripheral trigeminovascular neurons. Methods: In anesthetized male and female rats, single-unit recordings were used to assess effects of extracranial injections of onabotA (five injections, one unit each, diluted in 5 μl of saline were made along the lambdoid (two injection sites) and sagittal (two injection sites) suture) vs. vehicle on CSD-induced activation and sensitization of high-threshold (HT) and wide-dynamic range (WDR) dura-sensitive neurons in the SPV. Results: Single cell analysis of onabotA pretreatment effects on CSD-induced activation and sensitization of central trigeminovascular neurons in the SPV revealed the ability of this neurotoxin to prevent activation and sensitization of WDR neurons (13/20 (65%) vs. 4/16 (25%) activated neurons in the control vs. treated groups, p = 0.022, Fisher's exact). By contrast, onabotA pretreatment effects on CSD-induced activation and sensitization of HT neurons had no effect on their activation (12/18 (67%) vs. 4/7 (36%) activated neurons in the control vs. treated groups, p = 0.14, Fisher's exact). Regarding sensitization, we found that onabotA pretreatment prevented the enhanced responses to mechanical stimulation of the skin (i.e. responses reflecting central sensitization) in both WDR and HT neurons. In control but not treated WDR neurons, responses to brush (p = 0.004 vs. p = 0.007), pressure (p = 0.002 vs. p = 0.79) and pinch (p = 0.007 vs. 0.79) increased significantly two hours after CSD. Similarly, in control but not treated HT neurons, responses to brush (p = 0.002 vs. p = 0.79), pressure (p = 0.002 vs. p = 0.72) and pinch (p = 0.0006 vs. p = 0.28) increased significantly two hours after CSD. Unexpectedly, onabotA pretreatment prevented the enhanced responses of both WDR and HT neurons to mechanical stimulation of the dura (commonly reflecting peripheral sensitization). In control vs. treated WDR and HT neurons, responses to dural stimulation were enhanced in 70 vs. 25% (p = 0.017) and 78 vs. 27% (p = 0.017), respectively. Conclusions: The ability of onabotA to prevent activation and sensitization of WDR neurons is attributed to its preferential inhibitory effects on unmyelinated C-fibers. The inability of onabotA to prevent activation of HT neurons is attributed to its less extensive inhibitory effects on the thinly myelinated Aδ-fibers. These findings provide further pre-clinical evidence about differences and potentially complementary mechanisms of action of onabotA and calcitonin gene-related peptide-signaling neutralizing drugs. [ABSTRACT FROM AUTHOR]

Background: Atogepant is an oral, small-molecule, calcitonin gene–related peptide receptor antagonist for the preventive treatment of migraine. Methods: In the double-blind, phase 3 ADVANCE trial, participants with 4–14 migraine days/month were randomized to atogepant 10 mg, 30 mg, 60 mg, or placebo once daily for 12 weeks. We evaluated the time course of efficacy of atogepant for the preventive treatment of migraine. Analyses included change from baseline in mean monthly migraine days during each of the three 4-week treatment periods, change in weekly migraine days during weeks 1–4, and proportion of participants with a migraine on each day during the first week. Results: We analyzed 873 participants (n = 214 atogepant 10 mg, n = 223 atogepant 30 mg, n = 222 atogepant 60 mg, n = 214 placebo). For weeks 1–4, mean change from baseline in mean monthly migraine days ranged from −3.1 to −3.9 across atogepant doses vs −1.6 for placebo (p < 0.0001). For weeks 5–8 and 9–12, reductions in mean monthly migraine days ranged from −3.7 to −4.2 for atogepant vs −2.9 for placebo (p ≤ 0.012) and −4.2 to −4.4 for atogepant vs −3.0 for placebo (p < 0.0002), respectively. Mean change from baseline in weekly migraine days in week 1 ranged from −0.77 to −1.03 for atogepant vs −0.29 with placebo (p < 0.0001). Percentages of participants reporting a migraine on post-dose day 1 ranged from 10.8% to 14.1% for atogepant vs 25.2% with placebo (p ≤ 0.0071). Conclusion: Atogepant demonstrated treatment benefits as early as the first full day after treatment initiation, and sustained efficacy across each 4-week interval during the 12-week treatment period. Clinical trial registration: ClinicalTrials.gov identifier: NCT03777059 [ABSTRACT FROM AUTHOR]

Background: Migraine is associated with obesity. These analyses evaluated weight change with atogepant used as a preventive migraine treatment., Methods: Five atogepant clinical trials in adults with migraine (one phase 2b/3; four phase 3) were included: Three 12-week, randomized, placebo-controlled trials (episodic migraine: two; chronic migraine: one); one 40-week, open-label extension trial and one 52-week, standard care, randomized, long-term safety trial in episodic migraine. Change from baseline in body weight was measured., Results: Mean baseline body mass indexes were 30.0-30.7 kg/m 2 (pooled episodic migraine [United States only]) and 25.0-25.5 kg/m 2 (chronic migraine [East Asia, Europe, and North America]). More participants treated with atogepant 60 mg once-daily compared to placebo experienced ≥7% weight loss at any time in the pooled episodic migraine placebo-controlled trials (4.9% vs. 2.8%), chronic migraine placebo-controlled trial (5.8% vs. 2.0%), and pooled open-label extension and long-term safety trials (24.0% vs.14.7% in standard care [long-term safety only]). In the placebo-controlled trials, weight loss with atogepant 60 mg once-daily was observed at week 2 (pooled episodic migraine: -0.32%; chronic migraine: -0.39%), increasing at week 12 (pooled episodic migraine: -1.02%; chronic migraine: -1.50%); compared to weight gain with placebo at week 12 (pooled episodic migraine: +0.49%; chronic migraine: +0.10%). In the long-term episodic migraine studies, weight loss with atogepant 60 mg once-daily was observed at week 4 (long-term safety: -0.42%; open-label extension: -0.76%), increasing at week 40 (long-term safety: -2.38%; open-label extension: -2.09%)., Conclusion: Atogepant was associated with modest dose- and duration-dependent weight loss., Trial Registration: ClinicalTrials.gov identifiers: NCT02848326 (CGP-MD-01); NCT03777059 (3101-301-002); NCT03700320 (long-term safety trial); NCT03939312 (open-label extension trial); NCT03855137 (3101-303-002)., Competing Interests: Declaration of conflicting interestsThe authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: B.L.P. has served as a consultant and/or on the speaker bureaus for AbbVie, Amgen, Biohaven, Eli Lilly, GlaxoSmithKline, Impel, and Lundbeck Pharmaceuticals and has received research support from GlaxoSmithKline Pharmaceuticals, the Landsberger Foundation, Luitpold, and the National Institutes of Health. D.S.B. has no conflicts to report. J.A. has served as a consultant for AbbVie, Aeon, Dr. Reddy, Eli Lilly and Company, GlaxoSmithKline, Gore, Ipsen, Linpharma, Lundbeck, Merz, Neurolief, Pfizer, Satsuma, Scilex, Theranica, and Tonix; provided editorial services to Current Pain and Headache Reports, SELF, and Medscape; and received clinical trial support from Ipsen, Parema, and Satsuma. D.W.D. reports the following conflicts: (5-years): Consulting: Amgen, Atria, CapiThera Ltd., Cerecin, Ceruvia Lifesciences LLC, CoolTech, Ctrl M, Allergan, AbbVie, Biohaven, Escient, GlaxoSmithKline, Halion, Lundbeck, Eli Lilly, Novartis, Impel, Satsuma, Theranica, WL Gore, Genentech, Nocira, Perfood, Praxis, AYYA Biosciences, Revance, Pfizer. Honoraria: American Academy of Neurology, Headache Cooperative of the Pacific, Headache Cooperative of New England, Canadian Headache Society, MF Med Ed Research, Biopharm Communications, CEA Group Holding Company (Clinical Education Alliance LLC), Teva (speaking), Amgen Japan (speaking), Eli Lilly Canada (speaking), Lundbeck (speaking), Pfizer (speaking), Vector Psychometric Group, Clinical Care Solutions, CME Outfitters, Curry Rockefeller Group, DeepBench, Global Access Meetings, KLJ Associates, Academy for Continued Healthcare Learning, Majallin LLC, Medlogix Communications, Medica Communications LLC, MJH Lifesciences, Miller Medical Communications, WebMD Health/Medscape, Wolters Kluwer, Oxford University Press, Cambridge University Press. Non-profit board membership: American Brain Foundation, American Migraine Foundation, ONE Neurology, Precon Health Foundation, Global Patient Advocacy Coalition, Atria Health Collaborative, Atria Academy of Science and Medicine, Arizona Brain Injury Alliance, Domestic Violence HOPE Foundation/Panfila, CSF Leak Foundation. Research support: Department of Defense, National Institutes of Health, Henry Jackson Foundation, Sperling Foundation, American Migraine Foundation, Henry Jackson Foundation, Patient Centered Outcomes Research Institute (PCORI). Stock options/shareholder/patents/board of directors: Ctrl M (options), Aural analytics (options), Axon Therapeutics (board/options), ExSano (options), Palion (options), Keimon Medical (options), Man and Science, Healint (options), Theranica (options), Second Opinion/Mobile Health (options), Epien (options), Nocira (options), Matterhorn (shares), Ontologics (shares), King-Devick Technologies (options/board), Precon Health (options/board), ScotiaLyfe (board), EigenLyfe (options/board), AYYA Biosciences (options), Axon Therapeutics (options/board), Cephalgia Group (options/board), Atria Health (options/employee). Patent 17189376.1-1466:vTitle: Onabotulinum Toxin Dosage Regimen for Chronic Migraine Prophylaxis (Non-royalty bearing). Patent application submitted: Synaquell® (Precon Health). P.J.G. reports support for the present study and personal fees during the conduct of the study from AbbVie; a grant from Celgene; personal fees from Aeon Biopharma, Amgen, BioDelivery Sciences International, Inc., CoolTech LLC, Dr Reddy's, Eli Lilly, Epalex, Impel NeuroPharma, Lundbeck, Novartis, Praxis, Sanofi, Satsuma, ShiraTronics, Teva Pharmaceuticals, and Tremeau; personal fees for advice through Gerson Lehrman Group, Guidepoint, SAI Med Partners, and Vector Metric; fees for educational materials from CME Outfitters, Omnia Education, and WebMD; fees for publishing from Massachusetts Medical Society and Oxford University Press; and fees for medicolegal advice in headache. He has a patent for Magnetic stimulation for headache, which is licensed to eNeura without fee. Y.L., R.D.A.F., J.H.S., B.D., and J.M.T. are employees of AbbVie and may hold AbbVie stock.

Background and Objectives: Three phase 3 trials demonstrated the efficacy and safety of atogepant in episodic migraine (EM) and chronic migraine (CM) across 12-week treatment periods. This analysis evaluates improvements in efficacy and functional outcomes in the first 4 weeks of treatment with the oral calcitonin gene-related peptide receptor antagonist, atogepant, for the preventive treatment of migraine., Methods: ADVANCE, ELEVATE, and PROGRESS were phase 3, multicenter, randomized, double-blind, placebo-controlled 12-week trials. ADVANCE and ELEVATE included participants aged 18-80 years with >1 year history of EM and 4-14 monthly migraine days (MMDs). ELEVATE required previous treatment failures to 2-4 classes of oral preventives. PROGRESS included participants aged 18-80 years with >1 year history of CM, ≥15 monthly headache days, and ≥8 MMDs. This analysis reports the atogepant 60 mg once daily (QD) and placebo treatment arms. Outcomes included efficacy endpoints (reporting a migraine day on day 1, change from baseline in weekly migraine days [WMDs] at weeks 1-4, and in MMDs in the first 4 weeks) and functional endpoints evaluated by the Activity Impairment in Migraine-Diary (AIM-D) at weeks 1-4 and the European Quality-of-Life 5-Dimension 5-Level (EQ-5D-5L) at weeks 1-2 and 4., Results: The modified intent-to-treat population included the ADVANCE (atogepant, n = 222; placebo, n = 214), ELEVATE (atogepant, n = 151; placebo, n = 154), and PROGRESS (atogepant, n = 256; placebo, n = 246) studies. Atogepant-treated participants had greater reductions in the proportion of participants with a migraine day on day 1. The odds ratio compared with placebo was 0.39 (95% CI 0.23-0.67; p = 0.0006) in ADVANCE, 0.53 (95% CI 0.29-0.94, p = 0.031) in ELEVATE, and 0.63 (95% CI 0.43-0.93, p = 0.021) in PROGRESS. Atogepant treatment reduced WMDs at weeks 1-4 and MMDs in the first 4 weeks, and improved AIM-D and EQ-5D-5L at all assessed timepoints for weeks 1-4 compared with placebo., Discussions: Atogepant 60 mg QD demonstrated superiority to placebo in efficacy and functional measures in the first 4 weeks of treatment across 3 preventive studies, 2 in EM and 1 in CM., Trial Registration: ClinicalTrials.gov NCT03777059; NCT04740827; NCT03855137. Submitted: 12/13/2018; 02/02/2021; 02/25/2019. First patient enrolled: 12/14/2018; 03/05/2021; 03/11/2019 clinicaltrials.gov/ct2/show/NCT03777059. clinicaltrials.gov/ct2/show/NCT04740827 clinicaltrials.gov/ct2/show/NCT03855137., Classification of Evidence: This study provides Class II evidence that atogepant 60 mg QD reduces migraine frequency and improves functional outcomes within 4 weeks of initiation in patients with EM and patients with CM.

Recently, we showed that while atogepant-a small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist-does not fully prevent activation of meningeal nociceptors, it significantly reduces a cortical spreading depression (CSD)-induced early response probability in C fibres and late response probability in Aδ fibres. The current study investigates atogepant effect on CSD-induced activation and sensitization of high threshold (HT) and wide dynamic range (WDR) central dura-sensitive trigeminovascular neurons. In anaesthetized male rats, single-unit recordings were used to assess effects of atogepant (5 mg/kg) versus vehicle on CSD-induced activation and sensitization of HT and WDR trigeminovascular neurons. Single cell analysis of atogepant pretreatment effects on CSD-induced activation and sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus revealed the ability of this small molecule CGRP receptor antagonist to prevent activation and sensitization of nearly all HT neurons (8/10 versus 1/10 activated neurons in the control versus treated groups, P = 0.005). In contrast, atogepant pretreatment effects on CSD-induced activation and sensitization of WDR neurons revealed an overall inability to prevent their activation (7/10 versus 5/10 activated neurons in the control versus treated groups, P = 0.64). Unexpectedly however, in spite of atogepant's inability to prevent activation of WDR neurons, it prevented their sensitization (as reflected their responses to mechanical stimulation of the facial receptive field before and after the CSD). Atogepant' ability to prevent activation and sensitization of HT neurons is attributed to its preferential inhibitory effects on thinly myelinated Aδ fibres. Atogepant's inability to prevent activation of WDR neurons is attributed to its lesser inhibitory effects on the unmyelinated C fibres. Molecular and physiological processes that govern neuronal activation versus sensitization can explain how reduction in CGRP-mediated slow but not glutamate-mediated fast synaptic transmission between central branches of meningeal nociceptors and nociceptive neurons in the spinal trigeminal nucleus can prevent their sensitization but not activation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)