Changes in JC virus-specific T cell responses during natalizumab treatment and in natalizumab-associated progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) induced by JC virus (JCV) is a risk for natalizumab-treated multiple sclerosis (MS) patients. Here we characterize the JCV-specific T cell responses in healthy donors and natalizumab-treated MS patients to reveal functional differences that may account for the development of natalizumab-associated PML. CD4 and CD8 T cell responses specific for all JCV proteins were readily identified in MS patients and healthy volunteers. The magnitude and quality of responses to JCV and cytomegalovirus (CMV) did not change from baseline through several months of natalizumab therapy. However, the frequency of T cells producing IL-10 upon mitogenic stimulation transiently increased after the first dose. In addition, MS patients with natalizumab-associated PML were distinguished from all other subjects in that they either had no detectable JCV-specific T cell response or had JCV-specific CD4 T cell responses uniquely dominated by IL-10 production. Additionally, IL-10 levels were higher in the CSF of individuals with recently diagnosed PML. Thus, natalizumab-treated MS patients with PML have absent or aberrant JCV-specific T cell responses compared with non-PML patients, and changes in T cell-mediated control of JCV replication may be a risk factor for developing PML. Our data suggest further approaches to improved monitoring, treatment and prevention of PML in natalizumab-treated patients.

Clinical outcomes in patients with relapsing-remitting multiple sclerosis who switch from natalizumab to delayed-release dimethyl fumarate: A multicenter retrospective observational study (STRATEGY).

BACKGROUND: Delayed-release dimethyl fumarate (DMF) may be a therapeutic option for patients with relapsing-remitting multiple sclerosis (RRMS) who are treated with natalizumab and require a change in therapy. However, there is limited information regarding predictors of favorable treatment outcomes in patients switching from natalizumab to DMF. Clinical practices and sequencing protocols vary. Herein, we present the clinical results, including annualized relapse rate (ARR) and risk of relapse, of a phase 4 retrospective observational study of patients with RRMS who switched from natalizumab to DMF in a community practice setting (STRATEGY). METHODS: STRATEGY was performed through a single time point medical record abstraction; no study visits or procedures were required. Key inclusion criteria included age ≥ 18 years, RRMS diagnosis (McDonald criteria, 2010 revised), ≥ 12 months of continuous treatment with natalizumab monotherapy before DMF initiation, and initiation of DMF ≥ 12 months before enrollment. Patients were eligible to enroll regardless of current DMF use. RESULTS: A total of 530 patients at 45 US sites enrolled, and 506 met the inclusion criteria and were included in the modified evaluable population for analysis. Mean (SD) age at DMF initiation was 47.0 (10.9) years, with a mean (SD) of 12.7 (7.2) years since MS diagnosis. The mean (SD) duration of natalizumab treatment was 3.4 (1.9) years, and the mean (SD) washout from natalizumab discontinuation to DMF initiation (n = 502) was 101.6 (164.0) days. Overall risk of relapse 12 months after DMF initiation was 19.6%. Overall unadjusted ARR was higher during the 12 months following initiation of DMF treatment compared with the 12 months following initiation of natalizumab treatment (rate ratio, 2.32 [95% CI, 1.69-3.18]; p < 0.0001), but was lower compared with that observed in the year before initiation of natalizumab (rate ratio, 0.51 [95% CI, 0.40-0.64]; p < 0.0001). At 1 year following initiation of DMF treatment, the relapse rate was lower for patients who did not experience a relapse during 1 year following initiation of natalizumab treatment than for those who did (rate ratio for relapse rate, 0.47 [95% CI, 0.16-1.38]; p = 0.1664). The relapse rate for patients who did not relapse during natalizumab treatment was significantly lower with a washout period of ≤ 90 days as compared with a washout period of > 90 days (rate ratio for relapse rate, 0.49 [95% CI, 0.26-0.90]; p = 0.0216). A total of 42 (8%) patients reported ≥ 1 adverse event leading to DMF discontinuation during the study; the most commonly reported events were gastrointestinal disorders (n = 21; 4%). CONCLUSIONS: Results from this multicenter retrospective observational study suggest that DMF may be an effective treatment option for patients who discontinue natalizumab in routine clinical practice. ARR was lower in patients who initiated DMF within 90 days of natalizumab discontinuation compared with patients who initiated DMF after 90 days of natalizumab discontinuation. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier NCT02159573.

Outcomes of switching directly to oral fingolimod from injectable therapies: Results of the randomized, open-label, multicenter, Evaluate Patient OutComes (EPOC) study in relapsing multiple sclerosis.

BACKGROUND: The Evaluate Patient OutComes (ClinicalTrials.gov Identifier: NCT01216072) study was conducted in North America to assess patient- and physician-reported treatment satisfaction in patients with relapsing multiple sclerosis (MS) who received oral fingolimod for 6 months after switching from an injectable disease-modifying therapy (iDMT), without an intervening washout. METHODS: In this open-label, multicenter study, patients were randomized 3:1 to once-daily fingolimod 0.5mg or iDMT. The primary study objective was to evaluate differences in satisfaction measured using the Treatment Satisfaction Questionnaire for Medication v1.4. RESULTS: Of 1053 patients randomized, 790 patients received fingolimod and 263 patients received iDMT. Treatment satisfaction improved significantly in patients who switched to fingolimod compared with those who continued iDMT. Patients also reported significant improvements in health-related quality of life, reduced depression, and reduced fatigue severity after a switch to fingolimod. No difference between the treatment groups was detected on the Patient Reported Indices for MS Activities scale. The safety profile of fingolimod was consistent with that reported in the pivotal phase 3 studies. The most commonly reported adverse events were more prevalent in patients who switched to fingolimod than in those who continued iDMT (headache: 12% vs 3%; fatigue: 12% vs 6%). No significant relationship between lymphocyte counts and infection rates was observed and there was no evidence of additive immune-system effects, which might be expected when switching to a different class of immunomodulatory therapy with no intervening washout. CONCLUSION: Patients who switched from iDMT to fingolimod had significant improvements in most self-reported outcomes compared with those who continued iDMT.