Plasma neurofilament light chain in children with relapsing MS receiving teriflunomide or placebo: A post hoc analysis of the randomized TERIKIDS trial.

BACKGROUND: The phase 3 TERIKIDS study demonstrated efficacy and manageable safety for teriflunomide versus placebo in children with relapsing multiple sclerosis (RMS). OBJECTIVE: Evaluate plasma neurofilament light chain (pNfL) concentrations in TERIKIDS. METHODS: Patients received placebo or teriflunomide (14 mg adult equivalent) for up to 96 weeks in the double-blind (DB) period. In the open-label extension (OLE), all patients received teriflunomide until up to 192 weeks after randomization. pNfL was measured using single-molecule array assay (Simoa® NF-light™). RESULTS: Baseline mean age was 14.5 years; 69.4% were female. Baseline geometric least square mean pNfL levels were similar for teriflunomide (n = 78) and placebo (n = 33) patients (19.83 vs 18.30 pg/mL). Over the combined DB and OLE periods, pNfL values were lower for teriflunomide versus placebo (analysis of variance p < 0.01; Week 192: 10.61 vs 17.32 pg/mL). Observed between-group pNfL differences were attenuated upon adjustment for gadolinium (Gd)-enhancing or new/enlarged T2 lesion counts at DB Week 24. Higher baseline pNfL levels were associated with shorter time since first MS symptom onset, higher baseline Gd-enhancing lesion counts and T2 lesion volume, and increased hazard of high magnetic resonance imaging activity or clinical relapse during the DB period. CONCLUSION: Teriflunomide treatment was associated with significantly reduced pNfL levels in children with RMS. CLINICALTRIALS.GOV IDENTIFIER: NCT02201108.

In vitro evaluation of the activity of teriflunomide against SARS-CoV-2 and the human coronaviruses 229E and OC43.

Previous data have suggested an antiviral effect of teriflunomide, including against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the agent underlying the ongoing COVID-19 pandemic. We undertook an in vitro investigation to evaluate the inhibitory activity of teriflunomide against SARS-CoV-2 in a cell-based assay. Teriflunomide was added to Vero (kidney epithelial) cells that had been infected with SARS-CoV-2. A nucleocapsid immunofluorescence assay was performed to examine viral inhibition with teriflunomide and any potential cytotoxic effect. The 50% effective concentration (EC50) for teriflunomide against SARS-CoV-2 was 15.22 µM. No cytotoxicity was evident for teriflunomide in the Vero cells (i.e., the 50% cytotoxic concentration [CC50] was greater than the highest test concentration of 100 µM). The data were supported by additional experiments using other coronaviruses and human cell lines. In the SARS-CoV-2-infected Vero cells, the prodrug leflunomide had an EC50 of 16.49 µM and a CC50 of 54.80 µM. Our finding of teriflunomide-mediated inhibition of SARS-CoV-2 infection at double-digit micromolar potency adds to a growing body of evidence for a broad-ranging antiviral effect of teriflunomide.

Effectiveness and safety of switching to teriflunomide in older patients with relapsing multiple sclerosis: A real-world retrospective multicenter analysis.

BACKGROUND: The prevalence of multiple sclerosis (MS) in older people is increasing due to population aging and availability of effective disease-modifying therapies (DMTs). Treating older people with MS is complicated by age-related and MS-related comorbidities, immunologic effects of prior DMTs, and immunosenescence. Teriflunomide is a once-daily oral immunomodulator that has demonstrated efficacy and acceptable safety in clinical trials of adults with relapsing forms of MS (RMS). However, there are limited clinical trial and real-world data regarding teriflunomide use in people with MS aged >55 years. We analyzed real-world data to assess the effectiveness and safety of teriflunomide in older people with RMS who had switched to this agent from other DMTs. METHODS: People with RMS (relapsing remitting and active secondary progressive MS) aged ≥55 years who had switched from other DMTs to teriflunomide (7 mg or 14 mg) for ≥1 year were identified retrospectively by chart review at four sites in the United States. Data were extracted from medical records from 1 year pre-index to 2 years post-index (index defined as the teriflunomide start date). Assessments of effectiveness included annualized relapse rate (ARR), Expanded Disability Status Scale (EDSS) score, and magnetic resonance imaging (MRI) outcomes. Assessments of safety included lymphocyte counts, infections, and malignancies. We examined the effectiveness outcomes and lymphocyte counts within sub-groups defined by age (55-64, ≥65 years), sex, MS type, and prior route of DMT administration (oral, injectable, infusible). RESULTS: In total, 182 patients with RMS aged ≥55 years who switched from other DMTs to teriflunomide were identified (mean [SD] age: 62.5 [5.4] years). Mean ARR decreased from the start of teriflunomide treatment (mean [SD]: 0.43 [0.61]) to year 1 post-index (0.13 [0.65]) and year 2 post-index (0.05 [0.28]). Mean EDSS score remained unchanged from index (mean [SD]: 4.5 [1.8]) to 1 year post-treatment (4.5 [1.8]) and increased slightly at 2 years post-treatment (4.7 [1.7]). MRI scans from index and years 1 and 2 post-index compared with scans from the previous year indicated that most patients had stable or improved MRI outcomes at index (87.7%) and remained stable or improved at years 1 (96.0%) and 2 (93.6%). Lymphopenia decreased at years 1 (21.4%) and 2 post-index (14.8%, compared to index (23.5%). By 1 year post-index, fewer patients had grade 3 or 4 lymphopenia, and at 2 years post-index, there were no patients with grade 3 or 4 lymphopenia. Infection incidence was low (n = 40, 22.0%) and none were related to teriflunomide. The decreases in lymphopenia were driven by decreases among people who switched from a prior oral DMT; there were no notable differences in lymphopenia across the other sub-groups examined. ARR, EDSS score, and MRI outcomes across all sub-groups were similar to the results of the overall population. CONCLUSION: Our multicenter, longitudinal, retrospective study demonstrated that patients with RMS aged 55 or older switching to teriflunomide from other DMTs had significantly improved ARR, stable disability, and stable or improved MRI over up to 2 years' follow up. Safety results were acceptable with fewer patients exhibiting lymphopenia at years 1 and 2 post-index.

Vaccine Response in Patients With Multiple Sclerosis Receiving Teriflunomide.

Many patients with multiple sclerosis (MS) receive disease-modifying therapies (DMTs), such as teriflunomide, to reduce disease activity and slow progression. DMTs mediate their efficacy by modulating or suppressing the immune system, which might affect a patient's response to vaccination. As vaccines against the SARS-CoV-2 virus become available, questions have arisen around their efficacy and safety for patients with MS who are receiving DMTs. Data are beginning to emerge regarding the potential influence of certain DMTs on a patient's response to coronavirus disease 2019 (COVID-19) vaccines and are supported by evidence from vaccination studies of other pathogens. This review summarizes the available data on the response to vaccines in patients with MS who are receiving DMTs, with a focus on teriflunomide. It also provides an overview of the leading COVID-19 vaccines and current guidance around COVID-19 vaccination for patients with MS. Though few vaccination studies have been done for this patient population, teriflunomide appears to have minimal influence on the response to seasonal influenza vaccine. The evidence for other DMTs (e.g., fingolimod, glatiramer acetate) is less consistent: some studies suggest no effect of DMTs on vaccine response, whereas others show reduced vaccine efficacy. No unexpected safety signals have emerged in any vaccine study. Current guidance for patients with MS is to continue DMTs during COVID-19 vaccination, though adjusted timing of dosing for some DMTs may improve the vaccine response.

Teriflunomide Inhibits JCPyV Infection and Spread in Glial Cells and Choroid Plexus Epithelial Cells.

Several classes of immunomodulators are used for treating relapsing-remitting multiple sclerosis (RRMS). Most of these disease-modifying therapies, except teriflunomide, carry the risk of progressive multifocal leukoencephalopathy (PML), a severely debilitating, often fatal virus-induced demyelinating disease. Because teriflunomide has been shown to have antiviral activity against DNA viruses, we investigated whether treatment of cells with teriflunomide inhibits infection and spread of JC polyomavirus (JCPyV), the causative agent of PML. Treatment of choroid plexus epithelial cells and astrocytes with teriflunomide reduced JCPyV infection and spread. We also used droplet digital PCR to quantify JCPyV DNA associated with extracellular vesicles isolated from RRMS patients. We detected JCPyV DNA in all patients with confirmed PML diagnosis (n = 2), and in six natalizumab-treated (n = 12), two teriflunomide-treated (n = 7), and two nonimmunomodulated (n = 2) patients. Of the 21 patients, 12 (57%) had detectable JCPyV in either plasma or serum. CSF was uniformly negative for JCPyV. Isolation of extracellular vesicles did not increase the level of detection of JCPyV DNA versus bulk unprocessed biofluid. Overall, our study demonstrated an effect of teriflunomide inhibiting JCPyV infection and spread in glial and choroid plexus epithelial cells. Larger studies using patient samples are needed to correlate these in vitro findings with patient data.

Long-term safety and efficacy of teriflunomide in patients with relapsing multiple sclerosis: Results from the TOWER extension study.

BACKGROUND: In the phase 3 TOWER core study (NCT00751881), the efficacy and safety of teriflunomide compared with placebo were demonstrated in patients with relapsing forms of multiple sclerosis (RMS). Here, the long-term safety and efficacy outcomes from the TOWER extension study (NCT00751881) are reported. METHODS: All patients who entered the extension (N = 751) were assigned to teriflunomide 14 mg and assessed for long-term safety and efficacy. RESULTS: Of 751 patients in the TOWER extension study, 253, 265, and 233 patients received placebo/teriflunomide 14 mg, teriflunomide 7 mg/14 mg, and teriflunomide 14 mg/14 mg, respectively. Median teriflunomide exposure was 4.25 years (maximum 6.3 years). The overall frequency of adverse events (AEs) was comparable across treatment groups, but a higher proportion of patients in the teriflunomide 7 mg/14 mg (12.4%) and 14 mg/14 mg (12.4%) groups had serious AEs compared with the placebo/teriflunomide 14 mg group (6.4%). Alanine aminotransferase increase and hair thinning occurred at a higher frequency in the placebo/teriflunomide 14 mg group (11.2% and 14.3%, respectively) compared with the teriflunomide 7 mg/14 mg (3.0% and 4.5%, respectively) and 14 mg/14 mg groups (5.2% and 4.3%, respectively). The incidences of AEs of interest (hematologic and hepatic effects, peripheral neuropathy, hypertension, and malignancy) were low and comparable across treatment arms. Disability worsening and adjusted annualized relapse rates were low and stable over time, and mean Expanded Disability Status Scale scores were unchanged over time, for all treatment groups. CONCLUSION: In the TOWER extension study, the efficacy of teriflunomide 14 mg was maintained in patients with RMS. No new or unexpected AEs were observed with teriflunomide treatment, supporting a safety profile in the extension that was consistent with the core trial. These findings support the positive benefit:risk profile of teriflunomide as a long-term immunomodulatory therapy.

Effective anti-Alzheimer Aß therapy involves depletion of specific Aß oligomer subtypes.

BACKGROUND: Recent studies have implicated specific assembly subtypes of ß-amyloid (Aß) peptide, specifically soluble oligomers (soAß) as disease-relevant structures that may underlie memory loss in Alzheimer disease. Removing existing soluble and insoluble Aß assemblies is thought to be essential for any attempt at stabilizing brain function and slowing cognitive decline in Alzheimer disease. IV immunoglobulin (IVIg) therapies have been shown to contain naturally occurring polyclonal antibodies that recognize conformational neoepitopes of soluble or insoluble Aß assemblies including soAß. These naturally occurring polyclonal antibodies have been suggested to underlie the apparent clinical benefits of IVIg. However, direct evidence linking anti-Aß antibodies to the clinical bioactivity of IVIg has been lacking. METHODS: Five-month-old female Dutch APP E693Q mice were treated for 3 months with neat IVIg or with IVIg that had been affinity-depleted over immobilized Aß conformers in 1 of 2 assembly states. Memory was assessed in a battery of tests followed by quantification of brain soAß levels using standard anti-soAß antibodies. RESULTS: We provide evidence that NU4-type soAß (NU4-soAß) assemblies accumulate in the brains of Dutch APP E693Q mice and are associated with defects in memory, even in the absence of insoluble Aß plaques. Memory benefits were associated with depletion from APP E693Q mouse brain of NU4-soAß and A11-soAß but not OC-type fibrillar Aß oligomers. CONCLUSIONS: We propose that targeting of specific soAß assembly subtypes may be an important consideration in the therapeutic and/or prophylactic benefit of anti-Aß antibody drugs.

Nordihydroguaiaretic Acid Extends the Lifespan of Drosophila and Mice, Increases Mortality-Related Tumors and Hemorrhagic Diathesis, and Alters Energy Homeostasis in Mice.

Mesonordihydroguaiaretic acid (NDGA) extends murine lifespan. The studies reported here describe its dose dependence, effects on body weight, toxicity-related clinical chemistries, and mortality-related pathologies. In flies, we characterized its effects on lifespan, food consumption, body weight, and locomotion. B6C3F1 mice were fed AIN-93M diet supplemented with 1.5, 2.5, 3.5, or 4.5 g NDGA/kg diet (1.59, 2.65, 3.71 and 4.77 mg/kg body weight/day) beginning at 12 months of age. Only the 3.5 mg/kg diet produced a highly significant increase in lifespan, as judged by either the Mantel-Cox log-rank test (p = .008) or the Gehan-Breslow-Wilcoxon test (p = .009). NDGA did not alter food intake, but dose-responsively reduced weight, suggesting it decreased the absorption or increased the utilization of calories. NDGA significantly increased the incidence of liver, lung, and thymus tumors, and peritoneal hemorrhagic diathesis found at necropsy. However, clinical chemistries found little evidence for overt toxicity. While NDGA was not overtly toxic at its therapeutic dosage, its association with severe end of life pathologies does not support the idea that NDGA consumption will increase human lifespan or health-span. The less toxic derivatives of NDGA which are under development should be explored as anti-aging therapeutics.

ß1-Adrenergic receptor blockade extends the life span of Drosophila and long-lived mice.

Chronic treatment with ß-adrenergic receptor (ßAR) agonists increases mortality and morbidity while ßAR antagonists (ß-blockers) decrease all-cause mortality for those at risk of cardiac disease. Levels of sympathetic nervous system ßAR agonists and ßAR activity increase with age, and this increase may hasten the development of age-related mortality. Here, we show that ß-blockers extend the life span of healthy metazoans. The ß-blockers metoprolol and nebivolol, administered in food daily beginning at 12 months of age, significantly increase the mean and median life span of isocalorically fed, male C3B6F1 mice, by 10 and 6.4%, respectively (P < 0.05). Neither drug affected the weight or food intake of the mice, indicating that induced CR is not responsible for these effects, and that energy absorption and utilization are not altered by the drugs. Both ß-blockers were investigated to control for their idiosyncratic, off-target effects. Metoprolol and nebivolol extended Drosophila life span, without affecting food intake or locomotion. Thus, ßAR antagonists are capable of directly extending the life span of two widely divergent metazoans, suggesting that these effects are phylogenetically highly conserved. Thus, long-term use of ß-blockers, which are generally well-tolerated, may enhance the longevity of healthy humans.

FDA-approved drugs that protect mammalian neurons from glucose toxicity slow aging dependent on cbp and protect against proteotoxicity.

Screening a library of drugs with known safety profiles in humans yielded 30 drugs that reliably protected mammalian neurons against glucose toxicity. Subsequent screening demonstrated that 6 of these 30 drugs increase lifespan in C. elegans: caffeine, ciclopirox olamine, tannic acid, acetaminophen, bacitracin, and baicalein. Every drug significantly reduced the age-dependent acceleration of mortality rate. These protective effects were blocked by RNAi inhibition of cbp-1 in adults only, which also blocks protective effects of dietary restriction. Only 2 drugs, caffeine and tannic acid, exhibited a similar dependency on DAF-16. Caffeine, tannic acid, and bacitracin also reduced pathology in a transgenic model of proteotoxicity associated with Alzheimer's disease. These results further support a key role for glucose toxicity in driving age-related pathologies and for CBP-1 in protection against age-related pathologies. These results also provide novel lead compounds with known safety profiles in human for treatment of age-related diseases, including Alzheimer's disease and diabetic complications.

Days to criterion as an indicator of toxicity associated with human Alzheimer amyloid-beta oligomers.

OBJECTIVE: Recent evidence suggests that high molecular weight soluble oligomeric Abeta (oAbeta) assemblies (also known as Abeta-derived diffusible ligands, or ADDLs) may represent a primary neurotoxic basis for cognitive failure in Alzheimer disease (AD). To date, most in vivo studies of oAbeta/ADDLs have involved injection of assemblies purified from the cerebrospinal fluid of human subjects with AD or from the conditioned media of Abeta-secreting cells into experimental animals. We sought to study the bioactivities of endogenously formed oAbeta/ADDLs generated in situ from the physiological processing of human amyloid precursor protein (APP) and presenitin1 (PS1) transgenes. METHODS: We produced and histologically characterized single transgenic mice overexpressing APP(E693Q) or APP(E693Q) X PS1DeltaE9 bigenic mice. APP(E693Q) mice were studied in the Morris water maze (MWM) task at 6 and 12 months of age. Following the second MWM evaluation, mice were sacrificed, and brains were assayed for Abetatotal, Abeta40, Abeta42, and oAbeta/ADDLs by enzyme-linked immunosorbent assay (ELISA) and were also histologically examined. Based on results from the oAbeta/ADDL ELISA, we assigned individual APP(E693Q) mice to either an undetectable oAbeta/ADDLs group or a readily detectable oAbeta/ADDLs group. A days to criterion (DTC) analysis was used to determine delays in acquisition of the MWM task. RESULTS: Both single transgenic and bigenic mice developed intraneuronal accumulation of APP/Abeta, although only APP(E693Q) X PS1Delta9 bigenic mice developed amyloid plaques. The APP(E693Q) mice did not develop amyloid plaques at any age studied, up to 30 months. APP(E693Q) mice were tested for spatial learning and memory, and only 12-month-old APP(E693Q) mice with readily detectable oAbeta/ADDLs displayed a significant delay in acquisition of the MWM task when compared to nontransgenic littermates. INTERPRETATION: These data suggest that cerebral oAbeta/ADDL assemblies generated in brain in situ from human APP transgenes may be associated with cognitive impairment. We propose that a DTC analysis may be a sensitive method for assessing the cognitive impact in mice of endogenously generated oligomeric human Abeta assemblies. ANN NEUROL 2010.

Amyloid-beta oligomers: possible roles as key neurotoxins in Alzheimer's Disease.

Alzheimer's disease is the most common form of senile dementia. Although the amyloid-beta peptide was identified in 1984 as the major constituent of the senile plaques that characterize the disease, accumulating evidence indicates that the plaque density does not correspond well to the concurrent disease state. In order to resolve this disconnect, a number of recent studies have shifted away from the senile plaque and classical fibrillar forms of amyloid toward a less well structured species as the proximate neurotoxic factor underlying cognitive failure in Alzheimer's disease: soluble amyloid-beta peptide oligomer (also known as the amyloid-beta peptide-derived diffusible ligand). Paradoxically, several studies in the last 2 years have shown that picomolar levels of amyloid-beta peptide have neutral activity or perhaps even an essential role in learning and memory. Here we highlight some of the key observations underlying the growing focus on the amyloid-beta peptide oligomer.

SOD isoforms play no role in lifespan in ad lib or dietary restricted conditions, but mutational inactivation of SOD-1 reduces life extension by cold.

The free radical theory of aging is one of the most prominent theories of aging and senescence, but has yet to be definitively proven. If free radicals are the cause of senescence, then the cellular anti-oxidant system should play a large role in lifespan determination. Because superoxide dismutase (SOD) plays a central role in detoxifying superoxide radicals, we have examined the effects of mutational inactivation of each isoform of sod on normal lifespan and lifespan extension by dietary restriction (DR) or cold-/hypothermic-induced longevity (CHIL). We find no significant decrease in lifespan for control worms or worms undergoing DR when sod isoforms are knocked-out even though sod mutational inactivation produces hypersensitivity to paraquat. In contrast, sod-1 inactivation significantly reduces lifespan extension by CHIL, suggesting that CHIL requires a specific genetic program beyond simple reduction in metabolic rate. Furthermore, CHIL paradoxically increases lifespan while reducing resistance to oxidative stress, further disassociating oxidative stress resistance and lifespan.

The RNA-binding proteins PUF-5, PUF-6, and PUF-7 reveal multiple systems for maternal mRNA regulation during C. elegans oogenesis.

In metazoans, many mRNAs needed for embryogenesis are produced during oogenesis and must be tightly regulated during the complex events of oocyte development. In C. elegans, translation of the Notch receptor GLP-1 is repressed during oogenesis and is then activated specifically in anterior cells of the early embryo. The KH domain protein GLD-1 represses glp-1 translation during early stages of meiosis, but the factors that repress glp-1 during late oogenesis are not known. Here, we provide evidence that the PUF domain protein PUF-5 and two nearly identical PUF proteins PUF-6 and PUF-7 function during a specific period of oocyte differentiation to repress glp-1 and other maternal mRNAs. Depletion of PUF-5 and PUF-6/7 together caused defects in oocyte formation and early embryonic cell divisions. Loss of PUF-5 and PUF-6/7 also caused inappropriate expression of GLP-1 protein in oocytes, but GLP-1 remained repressed in meiotic germ cells. PUF-5 and PUF-6/7 function was required directly or indirectly for translational repression through elements of the glp-1 3' untranslated region. Oogenesis and embryonic defects could not be rescued by loss of GLP-1 activity, suggesting that PUF-5 and PUF-6/7 regulate other mRNAs in addition to glp-1. PUF-5 and PUF-6/7 depletion, however, did not perturb repression of the maternal factors GLD-1 and POS-1, suggesting that subsets of maternal gene products may be regulated by distinct pathways. Interestingly, PUF-5 protein was detected exclusively during mid to late oogenesis but became undetectable prior to completion of oocyte differentiation. These results reveal a previously unknown maternal mRNA control system that is specific to late stages of oogenesis and suggest new functions for PUF family proteins in post-mitotic differentiation. Multiple sets of RNA-binding complexes function in different domains of the C. elegans germ line to maintain silencing of Notch/glp-1 and other mRNAs.

A novel function for the Sm proteins in germ granule localization during C. elegans embryogenesis.

General mRNA processing factors are traditionally thought to function only in the control of global gene expression. Here we show that the Sm proteins, core components of the splicesome, also regulate germ granules during early C. elegans development. Germ granules are large cytoplasmic particles that localize to germ cells and their precursors during embryogenesis of diverse organisms. In C. elegans, germ granules, called P granules, are segregated to the germline precursor cells during embryogenesis by asymmetric cell division, and they remain in germ cells at all stages of development. We found that at least some Sm proteins are components of P granules. Moreover, disruption of Sm activity caused defects in P granule localization to the germ cell precursors during early embryogenesis. In contrast, loss of other splicing factor activities had no effect on germ granule control in the embryo. These observations suggest that the Sm proteins control germ granule integrity and localization in the early C. elegans embryo and that this role is independent of pre-mRNA splicing. Thus, a highly conserved splicing factor may have been adapted to control both snRNP biogenesis and the localization of components important for germ cell function.