{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:54:16Z","timestamp":1792788856321,"version":"4.5.0"},"reference-count":23,"publisher":"FapUNIFESP (SciELO)","issue":"9","license":[{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"am","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","award":["303379\/2018-9"],"award-info":[{"award-number":["303379\/2018-9"]}],"id":[{"id":"https:\/\/ror.org\/03swz6y49","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Rev. Assoc. Med. Bras."],"abstract":"<jats:p>SUMMARY  OBJECTIVE: The aim of this study was to explore the real-world effectiveness of semiannual versus annual rituximab maintenance administration in patients with refractory idiopathic inflammatory myopathies.  METHODS: In this single-center, retrospective longitudinal study (2010\u20132025), 45 adults with refractory idiopathic inflammatory myopathies received two initial rituximab infusions (1 g on days 0 and 15). Maintenance rituximab was administered every 6 months (semiannual group, n=14) or every 12 months (annual group, n=31). Baseline immunosuppressive therapy was maintained, and glucocorticoid tapering was guided by clinical and laboratory parameters. Outcomes at months 6\u201312 and 18\u201324 included the need for rescue therapies: intravenous methylprednisolone (3 g total) and immunoglobulin (2 g\/kg), or prednisone dose escalation.  RESULTS: Baseline demographics, refractory idiopathic inflammatory myopathies subtypes, rituximab indications (cutaneous, muscular, articular, and\/or pulmonary activity), and peri- rituximab medications (within 2 months before\/after infusion) did not differ significantly between groups (p&gt;0.05). No statistically significant differences in the frequency of rescue therapy use at 6\u201312 and 18\u201324 months were detected between the two regimens. Intragroup analysis demonstrated significant reductions in relapse rates and rescue therapy requirements over time (p&lt;0.05), suggesting improvement in both cohorts.  CONCLUSION: In this exploratory cohort, no statistically significant differences were detected between semiannual and annual rituximab maintenance regimens with respect to clinical outcomes, although numerically higher relapse rates were observed in the annual group. These findings suggest that extended rituximab intervals may be feasible in resource-limited settings, but further prospective studies are needed to confirm these observations.<\/jats:p>","DOI":"10.1590\/1806-9282.20260564","type":"journal-article","created":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T11:15:56Z","timestamp":1792149356000},"source":"Crossref","is-referenced-by-count":0,"title":["A comparative analysis of semiannual versus annual rituximab maintenance in patients with refractory idiopathic inflammatory myopathies: a retrospective longitudinal real-world study"],"prefix":"10.1590","volume":"72","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6278-1485","authenticated-orcid":false,"given":"Rodrigo Lorenzetti","family":"Serrano","sequence":"first","affiliation":[{"name":"Universidade de S\u00e3o Paulo","place":["S\u00e3o Paulo, SP, Brazil"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1771-6174","authenticated-orcid":false,"given":"Fernando Henrique Carlos de","family":"Souza","sequence":"additional","affiliation":[{"name":"Universidade de S\u00e3o Paulo","place":["S\u00e3o Paulo, SP, Brazil"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2210-601X","authenticated-orcid":false,"given":"Renata","family":"Miossi","sequence":"additional","affiliation":[{"name":"Universidade de S\u00e3o Paulo","place":["S\u00e3o Paulo, SP, Brazil"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9521-608X","authenticated-orcid":false,"given":"Marlise S\u00edtima Mendes Sim\u00f5es","family":"Faria","sequence":"additional","affiliation":[{"name":"Universidade de S\u00e3o Paulo","place":["S\u00e3o Paulo, SP, Brazil"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3682-4517","authenticated-orcid":false,"given":"Samuel Katsuyuki","family":"Shinjo","sequence":"additional","affiliation":[{"name":"Universidade de S\u00e3o Paulo","place":["S\u00e3o Paulo, SP, Brazil"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"530","published-online":{"date-parts":[[2026]]},"reference":[{"issue":"1","key":"ref1","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1038\/s41572-021-00321-x","article-title":"Idiopathic inflammatory myopathies","volume":"7","author":"Lundberg IE","year":"2021","journal-title":"Nat Rev Dis Primers"},{"issue":"6","key":"ref2","doi-asserted-by":"crossref","first-page":"3288","DOI":"10.1093\/rheumatology\/keaf116","article-title":"Treatment guidelines for idiopathic inflammatory myopathies in adults: a comparative review","volume":"64","author":"Paik JJ","year":"2025","journal-title":"Rheumatology 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