Identification of Therapeutic Lag in Multiple Sclerosis

International audienceObjective: To develop a method that allows identification of the time to full clinically manifest effect of multiple sclerosis (MS) treatments (‘therapeutic lag’) on clinical disease activity.Background: In MS, treatment start or switch is prompted by evidence of disease activity, often presenting as relapses or disability progression. Whilst immunomodulatory therapies reduce disease activity, the time required to attain maximal effect is unclear.Design/Methods: Data from MSBase, a multinational MS registry, and OFSEP, the French national registry, were used. Patients diagnosed with MS, minimum 1-year exposure to MS treatment, minimum 3-year pre-treatment follow up and yearly review were included in the analysis. For analysis of disability progression, all events in the subsequent 5-year period were included in the analysis. Density curves, representing incidence of relapses and 6-month confirmed progression events, were separately constructed for each sufficiently represented therapy. Monte Carlo simulations were performed to identify the first local minimum of the first derivative after treatment start. This point represents the point of stabilisation of treatment effect, after the maximum treatment effect was observed. The method was developed using MSBase, and externally validated in OFSEP. A merged MSBase-OFSEP cohort was used for all subsequent analyses.Results: 11180 eligible treatment epochs were identified for analysis of relapses and 4088 treatment epochs for disability progression. There were no significant differences between the results of discovery and validation analyses. The duration of therapeutic lag for relapses was calculated for 10 therapies and ranged between 12–30 weeks. The duration of therapeutic lag for disability progression was calculated for 7 therapies and ranged between 30–70 weeks.Conclusions: We have developed, and externally validated, a method to objectively quantify the duration of therapeutic lag on relapses and disability progression in different therapies. This method will be applied in studies that will evaluate the effect of patient and disease characteristics on therapeutic lag

Determinants of Therapeutic Lag in Multiple Sclerosis

International audienceObjective: To explore the associations of patient and disease characteristics with the duration of therapeutic lag for relapses and disability progression.Background: Therapeutic lag represents the delay from initiation of therapy to attainment of full treatment effect. Understanding the determinants of therapeutic lag provides valuable information for personalised choice of therapy in multiple sclerosis (MS).Design/Methods: Data from MSBase, a multinational MS registry, and OFSEP, the French national registry, were used. Patients diagnosed with MS, minimum 1-year exposure to MS treatment, minimum 3-year pre-treatment follow up and yearly review were included in the analysis. By studying incidence of relapses and 6-month confirmed disability progression, the duration of therapeutic lag was calculated by identifying the first local minimum of the first derivative after treatment start in subgroups stratified by patient and disease characteristics. Pairwise analyses of univariate predictors were performed. Combinations of determinants that consistently drove differences in therapeutic lag in pair by pair analyses were included in the final model.Results: Baseline EDSS, ARR and sex were associated with duration of therapeutic lag on disability progression in univariate and pairwise bivariable analyses. In the final model, therapeutic lag was 27.8 weeks shorter in females with ARR6 compared to those with EDSS>=6 (26.6, 18.2–34.9 vs 54.3, 47.2–61.5). Baseline EDSS, ARR, sex and MS phenotype were associated with duration of therapeutic lag on relapses in univariate analyses. Pairwise bivariable analyses of the pairs of determinants suggested ependently associated with therapeutic lag. In the final model, therapeutic lag was shortest in those with RRMS and EDSS<6 compared to the other represented groups.Conclusions: We have utilised a novel method for the quantification of therapeutic lag in different patient groups. Baseline EDSS and ARR are the most important determinants of therapeutic lag for both disability progression and relapses

Comparison of switching to 6-week dosing of natalizumab versus continuing with 4-week dosing in patients with relapsing-remitting multiple sclerosis (NOVA) : a randomised, controlled, open-label, phase 3b trial

Background Treatment with natalizumab once every 4 weeks is approved for patients with relapsing-remitting multiple sclerosis, but is associated with a risk of progressive multifocal leukoencephalopathy. Switching to extended-interval dosing is associated with lower progressive multifocal leukoencephalopathy risk, but the efficacy of this approach is unclear. We aimed to assess the safety and efficacy of natalizumab once every 6 weeks compared with once every 4 weeks in patients with relapsing-remitting multiple sclerosis.Methods We did a randomised, controlled, open-label, phase 3b trial (NOVA) at 89 multiple sclerosis centres across 11 countries in the Americas, Europe, and Western Pacific. Included participants were aged 18-60 years with relapsing-remitting multiple sclerosis and had been treated with intravenous natalizumab 300 mg once every 4 weeks with no relapses for at least 12 months before randomisation, with no missed doses in the previous 3 months. Participants were randomly assigned (1:1), using a randomisation sequence generated by the study funder and contract personnel with interactive response technology, to switch to natalizumab once every 6 weeks or continue with once every 4 weeks. The centralised MRI reader, independent neurology evaluation committee, site examining neurologists, site backup examining neurologists, and site examining technicians were masked to study group assignments. The primary endpoint was the number of new or newly enlarging T2 hyperintense lesions at week 72, assessed in all participants who received at least one dose of assigned treatment and had at least one postbaseline MRI, relapse, or neurological examination or efficacy assessment. Missing primary endpoint data were handled under prespecified primary and secondary estimands: the primary estimand included all data, regardless of whether participants remained on the assigned treatment; the secondary estimand classed all data obtained after treatment discontinuation or study withdrawal as missing. Safety was assessed in all participants who received at least one dose of study treatment. Study enrolment is closed and an open-label extension study is ongoing. This study is registered with EudraCT, 2018-002145-11, and ClinicalTrials.gov, NCT03689972.Findings Between Dec 26, 2018, and Aug 30,2019,605 patients were assessed for eligibility and 499 were enrolled and assigned to receive natalizumab once every 6 weeks (n=251) or once every 4 weeks (n=248). After prespecified adjustments for missing data, mean numbers of new or newly enlarging T2 hyperintense lesions at week 72 were 0.20 (95% CI 0.07-0-63) in the once every 6 weeks group and 0.05 (0.01-0-22) in the once every 4 weeks group (mean lesion ratio 4.24 [95% CI 0.86-20-85]; p=0.076) under the primary estimand, and 0.31 (95% CI 0.12-0-82) and 0.06 (0.01-0-31; mean lesion ratio 4.93 [95% CI 1.05-23.20]; p=0.044) under the secondary estimand. Two participants in the once every 6 weeks group with extreme new or newly enlarging T2 hyperintense lesion numbers (&gt;= 25) contributed most of the excess lesions. Adverse events occurred in 194 (78%) of 250 participants in the once every 6 weeks group and 190 (77%) of 247 in the once every 4 weeks group, and serious adverse events occurred in 17 (7%) and 17 (7%), respectively. No deaths were reported. There was one case of asymptomatic progressive multifocal leukoencephalopathy (without clinical signs) in the once every 6 weeks group, and no cases in the once every 4 weeks group; 6 months after diagnosis, the participant was without increased disability and remained classified as asymptomatic.Interpretation We found a numerical difference in the mean number of new or newly enlarging T2 hyperintense lesions at week 72 between the once every 6 weeks and once every 4 weeks groups, which reached significance under the secondary estimand, but interpretation of statistical differences (or absence thereof) is limited because disease activity in the once every 4 weeks group was lower than expected. The safety profiles of natalizumab once every 6 weeks and once every 4 weeks were similar. Although this trial was not powered to assess differences in risk of progressive multifocal leukoencephalopathy, the occurrence of the (asymptomatic) case underscores the importance of monitoring and risk factor consideration in all patients receiving natalizumab. Copyright (C) 2022 Elsevier Ltd. All rights reserved

Comparison of switching to 6-week dosing of natalizumab versus continuing with 4-week dosing in patients with relapsing-remitting multiple sclerosis (NOVA): a randomised, controlled, open-label, phase 3b trial

Background Treatment with natalizumab once every 4 weeks is approved for patients with relapsing-remitting multiple sclerosis, but is associated with a risk of progressive multifocal leukoencephalopathy. Switching to extended-interval dosing is associated with lower progressive multifocal leukoencephalopathy risk, but the efficacy of this approach is unclear. We aimed to assess the safety and efficacy of natalizumab once every 6 weeks compared with once every 4 weeks in patients with relapsing-remitting multiple sclerosis.Methods We did a randomised, controlled, open-label, phase 3b trial (NOVA) at 89 multiple sclerosis centres across 11 countries in the Americas, Europe, and Western Pacific. Included participants were aged 18-60 years with relapsing-remitting multiple sclerosis and had been treated with intravenous natalizumab 300 mg once every 4 weeks with no relapses for at least 12 months before randomisation, with no missed doses in the previous 3 months. Participants were randomly assigned (1:1), using a randomisation sequence generated by the study funder and contract personnel with interactive response technology, to switch to natalizumab once every 6 weeks or continue with once every 4 weeks. The centralised MRI reader, independent neurology evaluation committee, site examining neurologists, site backup examining neurologists, and site examining technicians were masked to study group assignments. The primary endpoint was the number of new or newly enlarging T2 hyperintense lesions at week 72, assessed in all participants who received at least one dose of assigned treatment and had at least one postbaseline MRI, relapse, or neurological examination or efficacy assessment. Missing primary endpoint data were handled under prespecified primary and secondary estimands: the primary estimand included all data, regardless of whether participants remained on the assigned treatment; the secondary estimand classed all data obtained after treatment discontinuation or study withdrawal as missing. Safety was assessed in all participants who received at least one dose of study treatment. Study enrolment is closed and an open-label extension study is ongoing. This study is registered with EudraCT, 2018-002145-11, and ClinicalTrials.gov, NCT03689972.Findings Between Dec 26, 2018, and Aug 30,2019,605 patients were assessed for eligibility and 499 were enrolled and assigned to receive natalizumab once every 6 weeks (n=251) or once every 4 weeks (n=248). After prespecified adjustments for missing data, mean numbers of new or newly enlarging T2 hyperintense lesions at week 72 were 0.20 (95% CI 0.07-0-63) in the once every 6 weeks group and 0.05 (0.01-0-22) in the once every 4 weeks group (mean lesion ratio 4.24 [95% CI 0.86-20-85]; p=0.076) under the primary estimand, and 0.31 (95% CI 0.12-0-82) and 0.06 (0.01-0-31; mean lesion ratio 4.93 [95% CI 1.05-23.20]; p=0.044) under the secondary estimand. Two participants in the once every 6 weeks group with extreme new or newly enlarging T2 hyperintense lesion numbers (&gt;= 25) contributed most of the excess lesions. Adverse events occurred in 194 (78%) of 250 participants in the once every 6 weeks group and 190 (77%) of 247 in the once every 4 weeks group, and serious adverse events occurred in 17 (7%) and 17 (7%), respectively. No deaths were reported. There was one case of asymptomatic progressive multifocal leukoencephalopathy (without clinical signs) in the once every 6 weeks group, and no cases in the once every 4 weeks group; 6 months after diagnosis, the participant was without increased disability and remained classified as asymptomatic.Interpretation We found a numerical difference in the mean number of new or newly enlarging T2 hyperintense lesions at week 72 between the once every 6 weeks and once every 4 weeks groups, which reached significance under the secondary estimand, but interpretation of statistical differences (or absence thereof) is limited because disease activity in the once every 4 weeks group was lower than expected. The safety profiles of natalizumab once every 6 weeks and once every 4 weeks were similar. Although this trial was not powered to assess differences in risk of progressive multifocal leukoencephalopathy, the occurrence of the (asymptomatic) case underscores the importance of monitoring and risk factor consideration in all patients receiving natalizumab. Copyright (C) 2022 Elsevier Ltd. All rights reserved