{"id":2098,"date":"2026-05-26T23:10:56","date_gmt":"2026-05-26T23:10:56","guid":{"rendered":"https:\/\/wickedsister.evit.com.au\/index.php\/2026\/05\/26\/anti-jcv-virus-levels-on-anti-cd20\/"},"modified":"2026-05-26T23:10:56","modified_gmt":"2026-05-26T23:10:56","slug":"anti-jcv-virus-levels-on-anti-cd20","status":"publish","type":"post","link":"https:\/\/wickedsister.evit.com.au\/index.php\/2026\/05\/26\/anti-jcv-virus-levels-on-anti-cd20\/","title":{"rendered":"Anti- JCV Virus levels on anti CD20"},"content":{"rendered":"<div class=\"twitter-share\"><a href=\"https:\/\/twitter.com\/intent\/tweet?url=https%3A%2F%2Fmultiple-sclerosis-research.org%2F2026%2F05%2Fanti-jcv-virus-levels-on-anti-cd20%2F&amp;via=the_MSBlog\" class=\"twitter-share-button\" data-size=\"large\">Tweet<\/a><\/div>\n<p class=\"wp-block-paragraph\"><strong>Purpose\/introduction:&nbsp;<\/strong>The anti-JC virus (JCV) antibody index is used to stratify the risk of progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS), particularly with natalizumab therapy. B-cell-depleting therapies may alter antibody levels and potentially confound the estimation of PML risk. This study evaluated the effect of ocrelizumab on anti-JCV antibody indices during the first 2 years of treatment.<\/p>\n<p class=\"wp-block-paragraph\"><strong>Methods:&nbsp;<\/strong>We conducted a retrospective cohort study of 553 MS patients who initiated ocrelizumab between 2017 and 2019. Anti-JCV antibody indices were measured using the STRATIFY JCV assay at baseline and approximately every 6 months prior to subsequent infusions. Linear mixed-effects models were used to assess longitudinal changes in log-transformed JCV indices, adjusting for age, sex, and ethnicity. Secondary analyses evaluated serum B-cell counts and immunoglobulin levels. Sensitivity analyses addressed missing data.<\/p>\n<p class=\"wp-block-paragraph\"><strong>Results\/finding:&nbsp;<\/strong>There was no significant change in anti-JCV antibody index over time following ocrelizumab initiation (mean percent change per infusion cycle -0.049%, 95% CI: -0.449 to 0.351; p = 0.81). Results were consistent across sensitivity analyses and did not differ by age or sex. In contrast, peripheral B-cell counts declined significantly after treatment initiation and remained suppressed. Serum IgG, IgM, and IgA levels decreased modestly but significantly over time. JCV seroconversion occurred in 4.1% of initially seronegative patients, while seroreversion occurred in 6.6% of initially seropositive patients.<\/p>\n<p class=\"wp-block-paragraph\"><strong>Conclusion:&nbsp;<\/strong>Anti-JCV antibody indices remain stable during the first 2 years of ocrelizumab treatment despite marked B-cell depletion and modest reductions in serum immunoglobulins. These findings suggest that existing PML risk stratification tools based on anti-JCV antibody indices remain applicable during early ocrelizumab therapy.<\/p>\n<p><em>Source: <a href=\"https:\/\/multiple-sclerosis-research.org\/2026\/05\/anti-jcv-virus-levels-on-anti-cd20\/?utm_source=rss&amp;utm_medium=rss&amp;utm_campaign=anti-jcv-virus-levels-on-anti-cd20\" rel=\"nofollow noopener\" target=\"_blank\">multiple-sclerosis-research.org<\/a><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tweet Purpose\/introduction:&nbsp;The anti-JC virus (JCV) antibody index is used to stratify the risk of progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS), particularly with natalizumab therapy. B-cell-depleting therapies may alter antibody levels and potentially confound the estimation of PML risk. This study evaluated the effect&hellip;<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[11,15,9,8,13,14,12,10],"class_list":["post-2098","post","type-post","status-publish","format-standard","hentry","category-multiple-sclerosis-research","tag-brain-repair","tag-marburg-type-ms","tag-ms","tag-multiple-sclerosis","tag-myelin","tag-neuroregeneration","tag-oligodendrocyte","tag-remyelination"],"_links":{"self":[{"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/posts\/2098","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/comments?post=2098"}],"version-history":[{"count":0,"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/posts\/2098\/revisions"}],"wp:attachment":[{"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/media?parent=2098"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/categories?post=2098"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wickedsister.evit.com.au\/index.php\/wp-json\/wp\/v2\/tags?post=2098"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}