A risk for developing progressive multifocal leukoencephalopathy is a major barrier to natalizumab use. Extended dosing intervals have been proposed as a way to maintain therapeutic efficacy and reduce progressive multifocal leukoencephalopathy incidence. This is the first reported case of progressive multifocal leukoencephalopathy in a patient using an extended dosing regimen (300 mg/6 weeks). A close clinical and imaging monitoring allowed early detection, which is a major prognostic factor. A favorable outcome was seen with a therapy comprising plasma exchange therapy, mirtazapine, mefloquine and cidofovir. Further studies will be needed to assess the potential role of extended dosing intervals to improve prognosis in patients receiving natalizumab and also to measure its impact clinically and/or radiologically.

Introduction: Vortioxetine is a multimodal antidepressant drug that has been reported to have a positive impact on cognition, social function, and fatigue. Nevertheless, it has not been widely studied. Our objective was to explore the effects of vortioxetine on these and other parameters in patients with multiple sclerosis (MS) and depression. Patients and Methodology: This observational case series study included patients with MS and depression who received treatment with vortioxetine for at least 6 months. The patient history of depression and depressive symptoms was assessed. A neuropsychiatric evaluation was carried out using different scales, both before and after treatment. Results: Of the 25 patients who enrolled in the study, 17 completed the treatment. Significant improvements were observed in health status (EQ-5D; p = 0.002), mood (Beck’s Depression Inventory, BDI-II; p = 0.006), anxiety (State-Trait Anxiety Inventory, STAI-State; p = 0.021, and STAI-Trait; p = 0.011), and in the general health test (Short Form Health Survey, SF-36) for the vitality (p = 0.028) and mental health (p = 0.025) domains of the patients who completed the treatment. However, no statistically significant differences were observed in the cognitive tests related to attention, information processing speed, or fatigue. Conclusion: In this population, vortioxetine treatment was effective in reducing the symptoms of depression and improving anxiety, vitality, and mental health. In contrast, it did not produce any improvement in cognition or fatigue but an increase in sample size would be necessary to confirm these results.