{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T05:35:19Z","timestamp":1788240919864,"version":"build-2803163510"},"reference-count":29,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T00:00:00Z","timestamp":1773446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Background: Chronic migraine (CM) is a highly disabling and difficult-to-manage condition with a high pharmacological and economic burden. OnabotulinumtoxinA (BTx) was the first treatment specifically approved for CM. The main aim of this study was to assess whether the initiation of BTx is associated with discontinuation of previously prescribed preventive therapies. Methods: This study was a prospective cohort investigation conducted in two headache centers: Carlo Besta (Milan) and Policlinico Campus Bio-Medico (Rome). We included patients with CM and previous oral preventive treatments initiating BTx. We analyzed persistence with preventive therapies over 12 months of follow-up and evaluated the conversion rate from chronic to episodic migraine (EM), along with change in migraine days, symptomatic intake, and HIT-6. Results: A total of 95 patients were included in the main analysis, showing a discontinuation of treatment in 28.4% of patients at 12 months. In the exploratory analysis, a CM to EM conversion rate of 58.9% was achieved at 12 months; meanwhile, HIT-6, migraine days, and symptomatic intake showed a sizeable improvement. Conclusion: Treatment with BTx was associated with a reduction in drug burden at 12 months and a CM to EM conversion rate of almost 60% at 12 months, also contributing to a reduction in the economic burden of the disease.<\/jats:p>","DOI":"10.3390\/toxins18030143","type":"journal-article","created":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T08:41:26Z","timestamp":1773650486000},"page":"143","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["OnabotulinumToxinA Reduces Pharmacological Burden in Chronic Migraine Patients: A Two-Center Prospective Cohort Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4834-2045","authenticated-orcid":false,"given":"Danilo Antonio","family":"Montisano","sequence":"first","affiliation":[{"name":"Headache Center, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20131 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8570-4175","authenticated-orcid":false,"given":"Alessandra","family":"Parisi","sequence":"additional","affiliation":[{"name":"Headache Center, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20131 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7433-7779","authenticated-orcid":false,"given":"Alberto","family":"Raggi","sequence":"additional","affiliation":[{"name":"Neurology, Public Health and Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5934-5535","authenticated-orcid":false,"given":"Claudia","family":"Altamura","sequence":"additional","affiliation":[{"name":"Headache and Neurosonology Unit, Fondazione Policlinico Campus Bio-Medico, Universit\u00e0 Campus Bio-Medico Di Roma, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-3387-4013","authenticated-orcid":false,"given":"Luigi","family":"D\u2019Onofrio","sequence":"additional","affiliation":[{"name":"Headache and Neurosonology Unit, Fondazione Policlinico Campus Bio-Medico, Universit\u00e0 Campus Bio-Medico Di Roma, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-5191-7628","authenticated-orcid":false,"given":"Marilena","family":"Marcosano","sequence":"additional","affiliation":[{"name":"Headache and Neurosonology Unit, Fondazione Policlinico Campus Bio-Medico, Universit\u00e0 Campus Bio-Medico Di Roma, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luisa","family":"Fofi","sequence":"additional","affiliation":[{"name":"Headache and Neurosonology Unit, Fondazione Policlinico Campus Bio-Medico, Universit\u00e0 Campus Bio-Medico Di Roma, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5003-1409","authenticated-orcid":false,"given":"Alessia","family":"Marcassoli","sequence":"additional","affiliation":[{"name":"Neurology, Public Health and Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9594-9336","authenticated-orcid":false,"given":"Fabrizio","family":"Vernieri","sequence":"additional","affiliation":[{"name":"Headache and Neurosonology Unit, Fondazione Policlinico Campus Bio-Medico, Universit\u00e0 Campus Bio-Medico Di Roma, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Licia","family":"Grazzi","sequence":"additional","affiliation":[{"name":"Headache Center, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20131 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1186\/s10194-024-01889-x","article-title":"Hallmarks of primary headache: Part 1\u2014Migraine","volume":"25","author":"Raggi","year":"2024","journal-title":"J. Headache Pain"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Headache Classification Committee of the International Headache Society (IHS) (2018). The International Classification of Headache Disorders, 3rd edition. Cephalalgia, 38, 1\u2013211.","DOI":"10.1177\/0333102417738202"},{"key":"ref_3","first-page":"62-e1","article-title":"The cost and the value of treatment of medication overuse headache in Italy: A longitudinal study based on patient-derived data","volume":"27","author":"Raggi","year":"2019","journal-title":"Eur. J. Neurol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1186\/s13561-023-00459-2","article-title":"Economic burden of chronic migraine in OECD countries: A systematic review","volume":"13","author":"Eltrafi","year":"2023","journal-title":"Health Econ. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1315","DOI":"10.1016\/S0140-6736(18)30478-1","article-title":"Migraine","volume":"391","author":"Dodick","year":"2018","journal-title":"Lancet"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.ncl.2022.05.005","article-title":"Chronic migraine: Diagnosis and management","volume":"41","author":"Kung","year":"2023","journal-title":"Neurol. Clin."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"793","DOI":"10.1177\/0333102410364676","article-title":"OnabotulinumtoxinA for treatment of chronic migraine: Results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 1 trial","volume":"30","author":"Aurora","year":"2010","journal-title":"Cephalalgia"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"921","DOI":"10.1111\/j.1526-4610.2010.01678.x","article-title":"OnabotulinumtoxinA for treatment of chronic migraine: Pooled results from the double-blind, randomized, placebo-controlled phases of the PREEMPT clinical program","volume":"50","author":"Dodick","year":"2010","journal-title":"Headache"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"804","DOI":"10.1177\/0333102410364677","article-title":"OnabotulinumtoxinA for treatment of chronic migraine: Results from the double-blind, randomized, placebo-controlled phase of the PREEMPT 2 trial","volume":"30","author":"Diener","year":"2010","journal-title":"Cephalalgia"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1038\/s41582-024-01002-5","article-title":"Insights from 25 years of onabotulinumtoxinA in migraine\u2014Mechanisms and management","volume":"20","author":"Alpuente","year":"2024","journal-title":"Nat. Rev. Neurol."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Montisano, D.A., Giossi, R., Canella, M., Altamura, C., Marcosano, M., Vernieri, F., Raggi, A., and Grazzi, L. (2024). Reducing the Impact of Headache and Allodynia Score in Chronic Migraine: An Exploratory Analysis from the Real-World Effectiveness of Anti-CGRP Monoclonal Antibodies Compared to Onabotulinum Toxin A (RAMO) Study. Toxins, 16.","DOI":"10.3390\/toxins16040178"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1186\/s10194-024-01721-6","article-title":"Real-world effectiveness of anti-CGRP monoclonal antibodies compared to onabotulinumtoxinA (RAMO) in chronic migraine: A retrospective, observational, multicenter, cohort study","volume":"25","author":"Grazzi","year":"2024","journal-title":"J. Headache Pain"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1186\/s10194-023-01594-1","article-title":"The comparative effectiveness of migraine preventive drugs: A systematic review and network meta-analysis","volume":"24","author":"Lampl","year":"2023","journal-title":"J. Headache Pain"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"5762","DOI":"10.1007\/s00415-024-12512-z","article-title":"Effectiveness and safety of pharmacological prophylaxis for chronic migraine: A systematic review and network meta-analysis","volume":"271","author":"Zhao","year":"2024","journal-title":"J. Neurol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1186\/s10194-024-01735-0","article-title":"The impact of primary headaches on disability outcomes: A literature review and meta-analysis to inform future iterations of the Global Burden of Disease study","volume":"25","author":"Montisano","year":"2024","journal-title":"J. Headache Pain"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1212\/CPJ.0000000000001037","article-title":"Medication overuse and headache burden: Results from the CaMEO study","volume":"11","author":"Schwedt","year":"2021","journal-title":"Neurol. Clin. Pract."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"353","DOI":"10.5414\/CP203853","article-title":"Relationship between polypharmacy and adverse events","volume":"59","author":"Mabuchi","year":"2021","journal-title":"Int. J. Clin. Pharmacol. Ther."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1543","DOI":"10.1177\/03331024221123058","article-title":"Effectiveness of onabotulinumtoxinA (BOTOX\u00ae) for the preventive treatment of chronic migraine: A meta-analysis on 10 years of real-world data","volume":"42","author":"Ducros","year":"2022","journal-title":"Cephalalgia"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Chamani, G., Jasim, H., Minston, A., Dias, M.F., Poluha, R.L., Gon\u00e7alves, D.A.G., Christidis, M., Al-Moraissi, E.A., Christidis, N., and De la Torre Canales, G. (2026). Botulinum Toxin Type A for the Prevention of Migraines: An Umbrella Review of Systematic Reviews. Toxins, 18.","DOI":"10.3390\/toxins18010033"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1212\/WNL.0000000000004177","article-title":"Comorbid Pain and Migraine Chronicity: The Chronic Migraine Epidemiology and Outcomes Study","volume":"89","author":"Scher","year":"2017","journal-title":"Neurology"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5717","DOI":"10.1007\/s10072-022-06164-y","article-title":"Addressing the cost of chronic and episodic migraine and its main drivers: A short-term longitudinal analysis from a third-level Italian center","volume":"43","author":"Raggi","year":"2022","journal-title":"Neurol. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Guerzoni, S., Pellesi, L., Baraldi, C., Cainazzo, M.M., Negro, A., Martelletti, P., and Pini, L.A. (2017). Long-term treatment benefits and prolonged efficacy of onabotulinumtoxinA in patients affected by chronic migraine and medication overuse headache over 3 years of therapy. Front. Neurol., 8.","DOI":"10.3389\/fneur.2017.00586"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s10194-016-0591-3","article-title":"A two years open-label prospective study of onabotulinumtoxinA 195 U in medication overuse headache: A real-world experience","volume":"17","author":"Negro","year":"2015","journal-title":"J. Headache Pain"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"03331024251398011","DOI":"10.1177\/03331024251398011","article-title":"Combination preventive therapy with onabotulinumtoxinA and atogepant for chronic migraine: A 24-week, prospective, real-world evaluation (SYNERGY study)","volume":"45","author":"Iannone","year":"2025","journal-title":"Cephalalgia"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e16215","DOI":"10.1111\/ene.16215","article-title":"Evaluation of the concomitant use of prophylactic treatments in patients with migraine under anti-calcitonin gene-related peptide therapies: The PREVENAC study","volume":"31","author":"Quintas","year":"2024","journal-title":"Eur. J. Neurol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"03331024251378776","DOI":"10.1177\/03331024251378776","article-title":"The clinical outcome of patients starting monoclonal antibodies anti-CGRP with concomitant migraine preventive treatments","volume":"45","author":"Fofi","year":"2025","journal-title":"Cephalalgia"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2102","DOI":"10.1111\/ene.14331","article-title":"Evaluation of the concomitant use of oral preventive treatments and onabotulinumtoxinA in chronic migraine: The PREVENBOX study","volume":"27","author":"Alpuente","year":"2020","journal-title":"Eur. J. Neurol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1177\/0333102420974004","article-title":"Reversion from chronic migraine to episodic migraine: A new outcome measure","volume":"41","author":"Wang","year":"2020","journal-title":"Cephalalgia"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"963","DOI":"10.1023\/A:1026119331193","article-title":"A six-item short-form survey for measuring headache impact: The HIT-6\u2122","volume":"12","author":"Kosinski","year":"2003","journal-title":"Qual. Life Res."}],"container-title":["Toxins"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6651\/18\/3\/143\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T08:57:08Z","timestamp":1773651428000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6651\/18\/3\/143"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,14]]},"references-count":29,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,3]]}},"alternative-id":["toxins18030143"],"URL":"https:\/\/doi.org\/10.3390\/toxins18030143","relation":{},"ISSN":["2072-6651"],"issn-type":[{"value":"2072-6651","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,14]]}}}