{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T08:14:18Z","timestamp":1783498458927,"version":"3.55.0"},"reference-count":19,"publisher":"Springer Science and Business Media LLC","issue":"7","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Fundaci\u00f3 Instituci\u00f3 dels Centres de Recerca de Catalunya"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J Neurol"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Subcutaneous natalizumab offers greater convenience than intravenous administration, but pharmacokinetic differences have raised concerns about potential subclinical disease activity. Serum neurofilament light chain (sNfL) and glial fibrillary acidic protein (GFAP) are sensitive biomarkers of neuroaxonal damage and astroglial activation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this prospective, single-center cohort study, consecutive patients with relapsing\u2013remitting multiple sclerosis who transitioned from intravenous to subcutaneous natalizumab were followed for 12\u00a0months. Serum sNfL and GFAP were measured at baseline (prior to switch), and at 6 and 12\u00a0months using SIMOA technology. Additional clinical outcomes included annualized relapse rate (ARR), EDSS, and MRI activity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      23 patients were included (mean age 43.7\u00a0years; 91% female). Median disease duration was 14\u00a0years (IQR 8.1\u201322), median time on natalizumab was 5\u00a0years (IQR 3.3\u20137.9), baseline 2-year ARR was 0.09\u2009\u00b1\u20090.2, and median EDSS was 2.0 (IQR 2.0\u20133.5). Median sNfL\n                      <jats:italic>Z<\/jats:italic>\n                      -scores were 0.2 (IQR \u2212\u00a00.3\u20130.6) at baseline, 0.1 (IQR \u2212\u00a00.4\u20131.0) at 6\u00a0months, and 0.5 (IQR \u2212\u00a00.4\u20131.1) at 12\u00a0months, with no significant change over time (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.401). GFAP levels were similarly stable (87.7, 86.8, and 90.2\u00a0pg\/mL;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.957). ARR remained low and unchanged (0.09 pre- and post-switch;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20091.0), with no radiological activity observed. EDSS remained stable over follow-up.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In this small real-world cohort, switching from intravenous to subcutaneous natalizumab was associated with stable sNfL and GFAP levels over 12\u00a0months, alongside stable conventional clinical and MRI outcomes. These findings provide supplementary biomarker evidence broadly consistent with existing clinical trial and real-world data, but should be interpreted cautiously given the small sample size.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00415-026-13949-0","type":"journal-article","created":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T17:23:30Z","timestamp":1782149010000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Serum biomarkers remain stable after transitioning from intravenous to subcutaneous natalizumab in multiple sclerosis"],"prefix":"10.1007","volume":"273","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8221-865X","authenticated-orcid":false,"given":"Albert","family":"Mu\u00f1oz-Vendrell","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0632-4850","authenticated-orcid":false,"given":"Pablo","family":"Arroyo-Pereiro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4352-0730","authenticated-orcid":false,"given":"Isabel","family":"Le\u00f3n","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2221-8759","authenticated-orcid":false,"given":"Laura","family":"Bau","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6137-6583","authenticated-orcid":false,"given":"Elisabet","family":"Matas","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8054-0565","authenticated-orcid":false,"given":"Lucia","family":"Romero-Pinel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-7393-0057","authenticated-orcid":false,"given":"Sergio","family":"Roca-Pereira","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3725-0180","authenticated-orcid":false,"given":"Antonio","family":"Mart\u00ednez-Y\u00e9lamos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9889-2040","authenticated-orcid":false,"given":"Sergio","family":"Mart\u00ednez-Y\u00e9lamos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"13949_CR1","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.549842","author":"K Khoy","year":"2020","unstructured":"Khoy K, Mariotte D, Defer G et al (2020) Natalizumab in multiple sclerosis treatment: from biological effects to immune monitoring. 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PAP has received funding for travel and congress expenses from Amgen, Biogen, Merck, Novartis, Roche, and Sanofi. IL has received funding for travel and congress expenses from Biogen, Merck, Neuraxpharm, Novartis, and Roche. LB has received funding for travel and congress expenses and honoraria for lectures from Biogen, Bristol Myers Squibb, Merck, Novartis, and Roche. EM has received funding for travel and congress expenses and honoraria for lectures from Biogen, Bristol Myers Squibb, Janssen, Merck, and Roche. LRP has received funding for travel and congress expenses and honoraria for lectures from Amgen, Biogen, Bristol Myers Squibb, Merck, Neuraxpharm, Novartis, and Roche. AMY has received support for congress attendance from Biogen, Bristol Myers Squibb, Janssen, Merck, Novartis, Roche, and Sandoz. SMY has received support for congress attendance from Biogen, Bristol Myers Squibb, Janssen, Merck, Neuraxpharm, Novartis, Roche, and Sandoz. The institution where the authors work (Hospital Universitari de Bellvitge\/Institut d\u2019Investigaci\u00f3 Biom\u00e8dica de Bellvitge) has received in the last three years and dedicated exclusively to support the research of the Unit, fees for advisory council, collaborations, donations and advice from Almirall, Amgen\/ Horizon, Bayer, Biogen, Bristol Myers Squibb, Celgene, Genzyme, Janssen, Kern Pharma, Lilly, Merck, Organon, Pfizer, Neuraxpharm, Novartis, Roche, Sandoz, and Sanofi. The authors report no conflicts of interest directly related to this publication.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflicts of interest"}},{"value":"This study was approved by the Ethics Committee (CEIC) of Hospital Universitari de Bellvitge (reference number EOM020\/25). Patient confidentiality was managed in accordance with Spanish regulations, and with the ethical standards laid down in the\u00a01964 Declaration of Helsinki. Written informed consent was obtained from all participants prior to sample storage in the IDIBELL-ICO-HUB Biobank, following guidelines established by Spanish legislation (Real Decreto 1716\/2011) and CEIC approval.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}}],"article-number":"412"}}