{Reference Type}: Journal Article
{Title}: Influence of personalized extended interval dosing on the natalizumab wearing-off effect - a sub-study of the NEXT-MS trial.
{Author}: Toorop AA;Wessels MHJ;Gelissen LMY;Hoitsma E;Zeinstra EMPE;van Rooij LC;van Munster CEP;Vennegoor A;Mostert JP;Wokke BHA;Kalkers NF;Hoogervorst ELJ;van Eijk JJJ;Roosendaal CM;Kragt JJ;Eurelings M;van Genugten J;Nielsen J;Sinnige LGF;Kloosterziel ME;Arnoldus EPJ;van Dijk GW;Bouvy WH;Strijbis EMM;van Oosten BW;de Jong BA;Lissenberg-Witte BI;Rispens T;Uitdehaag BMJ;Killestein J;van Kempen ZLE;
{Journal}: J Neurol Sci
{Volume}: 462
{Issue}: 0
{Year}: 2024 Jun 22
{Factor}: 4.553
{DOI}: 10.1016/j.jns.2024.123102
{Abstract}: <B>OBJECTIVE: </B>Wearing-off symptoms during natalizumab treatment in multiple sclerosis are characterized by an increase of MS-related symptoms prior to natalizumab administration. The influence of extended interval dosing (EID) on wearing-off symptoms are important to consider, as this might cause hesitancy in initiating or continuing EID.<BR><B>METHODS: </B>Participants of the NEXT-MS trial, in which treatment intervals are adjusted based on drug concentrations, were divided into two groups: an extended group containing participants with at least one week of additional interval extension, and a group with a fixed interval during the trial (range 4-7 weeks). Changes in the occurrence, frequency, onset, and severity of wearing-off symptoms were evaluated.<BR><B>RESULTS: </B>255 participants were included (extended group n = 171, fixed group n = 84). The odds on occurrence of wearing-off symptoms in the extended group did not increase after extending the treatment interval. Additional analyses for frequency, onset, and severity of wearing-off symptoms showed no changes over time. Mean decrease in natalizumab drug concentration did not influence the frequency of wearing-off symptoms.<BR><B>CONCLUSIONS: </B>Wearing-off symptoms were not reinforced by further extending the natalizumab interval. Wearing-off symptoms might increase in a minority of patients after EID, although our data support the view that wearing-off symptoms appear to be unrelated to the decrease in natalizumab trough drug concentrations.