Lymphocyte counts and infection rates: Long-term fingolimod treatment in primary progressive MS

Immunomodulators and immunosuppressants for progressive multiple sclerosis: a network meta-analysis

BACKGROUND

In recent years a broader range of immunomodulatory and immunosuppressive treatment options have emerged for people with progressive forms of multiple sclerosis (PMS). While consensus supports these options as reducing relapses, their relative benefit and safety profiles remain unclear due to a lack of direct comparison trials.

OBJECTIVES

To compare through network meta-analysis the efficacy and safety of alemtuzumab, azathioprine, cladribine, cyclophosphamide, daclizumab, dimethylfumarate, diroximel fumarate, fingolimod, fludarabine, glatiramer acetate, immunoglobulins, interferon beta 1-a and beta 1-b, interferon beta-1b (Betaferon), interferon beta-1a (Avonex, Rebif), laquinimod, leflunomide, methotrexate, minocycline, mitoxantrone, mycophenolate mofetil, natalizumab, ocrelizumab, ofatumumab, ozanimod, pegylated interferon beta-1a, ponesimod, rituximab, siponimod, corticosteroids, and teriflunomide for PMS.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and Embase up to August 2022, as well as ClinicalTrials.gov and the WHO ICTRP.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that studied one or more treatments as monotherapy, compared to placebo or to another active agent, for use in adults with PMS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data. We performed data synthesis by pair-wise and network meta-analysis. We assessed the certainty of the body of evidence according to GRADE.

MAIN RESULTS

We included 23 studies involving a total of 10,167 participants. The most frequent (39% of studies) reason for a rating of high risk of bias was sponsor role in study authorship and data management and analysis. Other concerns were performance, attrition, and selective reporting bias, with 8.7% of studies at high risk of bias for all three of these domains. The common comparator for network analysis was placebo. Relapses over 12 months: assessed in one study (318 participants). None of the treatments assessed showed moderate or high certainty evidence compared to placebo. Relapses over 24 months: assessed in six studies (1622 participants). The number of people with clinical relapses is probably trivially reduced with rituximab (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.19 to 1.95; moderate certainty evidence). None of the remaining treatments assessed showed moderate or high certainty evidence compared to placebo. Relapses over 36 months: assessed in four studies (2095 participants). The number of people with clinical relapses is probably trivially reduced with interferon beta-1b (RR 0.82, 95% CI 0.73 to 0.93; moderate certainty evidence). None of the remaining treatments assessed showed moderate or high certainty evidence compared to placebo. Disability worsening over 24 months: assessed in 11 studies (5284 participants). None of the treatments assessed showed moderate or high certainty evidence compared to placebo. Disability worsening over 36 months: assessed in five studies (2827 participants). None of the treatments assessed showed moderate or high certainty evidence compared to placebo. Serious adverse events: assessed in 15 studies (8019 participants). None of the treatments assessed showed moderate or high certainty evidence compared to placebo. Discontinuation due to adverse events: assessed in 21 studies (9981 participants). The number of people who discontinued treatment due to adverse events is trivially increased with interferon beta-1a (odds ratio (OR) 2.93, 95% CI 1.64 to 5.26; high certainty evidence). The number of people who discontinued treatment due to adverse events is probably trivially increased with rituximab (OR 4.00, 95% CI 0.84 to 19.12; moderate certainty evidence); interferon beta-1b (OR 2.98, 95% CI 1.92 to 4.61; moderate certainty evidence); immunoglobulins (OR 1.95, 95% CI 0.99 to 3.84; moderate certainty evidence); glatiramer acetate (OR 3.98, 95% CI 1.48 to 10.72; moderate certainty evidence); natalizumab (OR 1.02, 95% CI 0.55 to 1.90; moderate certainty evidence); siponimod (OR 1.53, 95% CI 0.98 to 2.38; moderate certainty evidence); fingolimod (OR 2.29, 95% CI 1.46 to 3.60; moderate certainty evidence), and ocrelizumab (OR 1.24, 95% CI 0.54 to 2.86; moderate certainty evidence). None of the remaining treatments assessed showed moderate or high certainty evidence compared to placebo.

AUTHORS' CONCLUSIONS

The number of people with PMS with relapses is probably slightly reduced with rituximab at two years, and interferon beta-1b at three years, compared to placebo. Both drugs are also probably associated with a slightly higher proportion of withdrawals due to adverse events, as are immunoglobulins, glatiramer acetate, natalizumab, fingolimod, siponimod, and ocrelizumab; we have high confidence that this is the case with interferon beta-1a. We found only low or very low certainty evidence relating to disability progression for the included disease-modifying treatments compared to placebo, largely due to imprecision. We are also uncertain about the effect of interventions on serious adverse events, also because of imprecision. These findings are due in part to the short follow-up of the included RCTs, which lacked detection of less common severe adverse events. Moreover, the funding source of many included studies may have introduced bias into the results. Future research on PMS should include head-to-head rather than placebo-controlled trials, with a longer follow-up of at least three years. Given the relative rarity of PMS, controlled, non-randomised studies on large samples may usefully integrate data from pivotal RCTs. Outcomes valuable and meaningful to people with PMS should be consistently adopted and measured to permit the evaluation of relative effectiveness among treatments.

Sphingosine 1 phosphate promotes hypertension specific memory T cell trafficking in response to repeated hypertensive challenges

We have previously shown that effector memory (TEM) cells accumulate in the bone marrow (BM) and the kidney in response to l-NAME/high salt challenge. It is not well understood if measures to block the exodus of that effector memory cells prevent redistribution of these cells and protect from hypertension-induced renal damage. We hypothesized that that effector memory cells that accumulate in the bone marrow respond to repeated salt challenges and can be reactivated and circulate to the kidney. Thus, to determine if mobilization of bone marrow that effector memory cells and secondary lymphoid organs contribute to the hypertensive response to delayed salt challenges, we employed fingolimod (FTY720), an S1PR1 functional antagonist by downregulating S1PR, which inhibits the egress of that effector memory cells used effectively in the treatment of multiple sclerosis and cardiovascular diseases. We exposed wild-type mice to the l-NAME for 2 weeks, followed by a wash-out period, a high salt diet feeding for 4 weeks, a wash-out period, and then a second high salt challenge with or without fingolimod. A striking finding is that that effector memory cell egress was dramatically attenuated from the bone marrow of mice treated with fingolimod with an associated reduction of renal that effector memory cells. Mice receiving fingolimod were protected from hypertension. We found that wild-type mice that received fingolimod during the second high salt challenge had a marked decrease in the renal damage markers. CD3⁺ T cell infiltration was significantly attenuated in the fingolimod-treated mice. To further examine the redistribution of bone marrow that effector memory cells in response to repeated hypertensive stimuli, we harvested the bone marrow from CD45.2 mice following the repeated high salt protocol with or without fingolimod; that effector memory cells were sorted and adoptively transferred (AT) to CD45.1 naïve recipients. Adoptively transferred that effector memory cells from mice treated with fingolimod failed to home to the bone marrow and traffic to the kidney in response to a high salt diet. We conclude that memory T cell mobilization contributes to the predisposition to hypertension and end-organ damage for prolonged periods following an initial episode of hypertension. Blocking the exodus of reactivated that effector memory cells from the bone marrow protects the kidney from hypertension-induced end-organ damage.

Anemoside B4 ameliorates experimental autoimmune encephalomyelitis in mice by modulating inflammatory responses and the gut microbiota

BACKGROUND

Anemoside B4 (AB4) is a representative component of Pulsatilla decoction that is used in traditional Chinese medicine for treating inflammatory conditions. It is not known whether AB4 has beneficial effects on multiple sclerosis (MS).

METHODS

In the present study, we examined the preventative and therapeutic effects of AB4, and the possible mechanism by which it protects female mice against experimental autoimmune encephalomyelitis (EAE).

RESULTS

Preventative treatment with AB4 (given orally at 100 and 200 mg/kg for 18 days) reduced the clinical severity of EAE significantly (from 3.6 ± 1.3 to 1.8 ± 1.5 and 1.6 ± 0.6, respectively), and inhibited demyelination and inflammatory infiltration of the spinal cord. In the therapeutic protocol, oral administration of 200 mg/kg AB4 for 21 days after initiation of EAE significantly alleviated disease severity (from 2.6 ± 1.3 to 0.9 ± 0.6) and was as effective as the clinically used drug fingolimod (0.3 ± 0.6). Furthermore, both doses of AB4 significantly inhibited mRNA expression of TNF-α, IL-6, and IL-17, and STAT3 activation, in the spinal cord; and the ex vivo and iv vitro AB4 treatment markedly inhibited secretion of the three cytokines from lymphocytes of EAE mice upon in vitro restimulation. In addition, AB4 reversed the changes in the composition of the intestinal microbiome observed in EAE mice.

CONCLUSION

We reveal for the first time that AB4 protects against EAE by modulating inflammatory responses and the gut microbiota, demonstrating that AB4 may have potential as a therapeutic agent for treating MS in humans.

Sphingosine 1-phosphate Receptor Modulator Therapy for Multiple Sclerosis: Differential Downstream Receptor Signalling and Clinical Profile Effects

Lysophospholipids are a class of bioactive lipid molecules that produce their effects through various G protein-coupled receptors (GPCRs). Sphingosine 1-phosphate (S1P) is perhaps the most studied lysophospholipid and has a role in a wide range of physiological and pathophysiological events, via signalling through five distinct GPCR subtypes, S1PR1 to S1PR5. Previous and continuing investigation of the S1P pathway has led to the approval of three S1PR modulators, fingolimod, siponimod and ozanimod, as medicines for patients with multiple sclerosis (MS), as well as the identification of new S1PR modulators currently in clinical development, including ponesimod and etrasimod. S1PR modulators have complex effects on S1PRs, in some cases acting both as traditional agonists as well as agonists that produce functional antagonism. S1PR subtype specificity influences their downstream effects, including aspects of their benefit:risk profile. Some S1PR modulators are prodrugs, which require metabolic modification such as phosphorylation via sphingosine kinases, resulting in different pharmacokinetics and bioavailability, contrasting with others that are direct modulators of the receptors. The complex interplay of these characteristics dictates the clinical profile of S1PR modulators. This review focuses on the S1P pathway, the characteristics and S1PR binding profiles of S1PR modulators, the mechanisms of action of S1PR modulators with regard to immune cell trafficking and neuroprotection in MS, together with a summary of the clinical effectiveness of the S1PR modulators that are approved or in late-stage development for patients with MS. Sphingosine 1-phosphate receptor modulator therapy for multiple sclerosis: differential downstream receptor signalling and clinical profile effects (MP4 65540 kb).

Fingolimod and Dimethyl-Fumarate-Derived Lymphopenia is not Associated with Short-Term Treatment Response and Risk of Infections in a Real-Life MS Population

BACKGROUND

The association between treatment-related lymphopenia in multiple sclerosis, drug efficacy and the risk of infections is not yet fully understood.

OBJECTIVE

The objective of this study was to assess whether lymphopenia is associated with short-term treatment response and infection rate in a real-life multiple sclerosis population treated with fingolimod and dimethyl-fumarate. We assessed the associations between baseline absolute lymphocyte count and the lymphocyte mean percentage decrease at 6 and 12 months with treatment response and the occurrence of adverse events over 12 months in the entire cohort of patients and in the two treatment groups separately.

METHODS

This is a retrospective observational real-world study of patients with multiple sclerosis treated with fingolimod and dimethyl-fumarate at the MS Center of the University of Genoa between 2011 and 2018. Patients with at least 12 months of follow-up were eligible if [1] they had an Expanded Disability Status Scale assessment at baseline and 12 months after treatment onset, [2] they had undergone brain magnetic resonance imaging at baseline and after 12 months, and [3] absolute lymphocyte counts were available at baseline, 6 and 12 months. Patients shifting from dimethyl-fumarate to fingolimod or vice versa were excluded from the analysis.

RESULTS

In total, 137 and 75 patients treated with fingolimod and dimethyl-fumarate, respectively, were included in the analysis. At 12 months, fingolimod-treated patients were more likely to experience grade II and grade III lymphopenia compared with dimethyl-fumarate patients (p < 0.001, χ2 = 94) and had a higher lymphocyte mean percentage decrease (p < 0.001, U = 540). A higher number of previous therapies and a lower baseline absolute lymphocyte count were predictors of lymphopenia at 6 months (p = 0.047, odds ratio = 1.60 and p = 0.014, odds ratio = 1.1) and 12 months (p = 0.003, odds ratio = 1.97 and p = 0.023, odds ratio = 1.1). In fingolimod-treated patients only, female sex and a higher Expanded Disability Status Scale score were predictors of lymphopenia at 12 months (p = 0.006, odds ratio = 7.58 and p = 0.03, odds ratio = 1.56). Neither absolute lymphocyte count at 6 and 12 months nor the mean percentage decrease at 6 and 12 months predicted No Evidence of Disease Activity (NEDA-3) status at 1 year, the occurrence of relapses, disease activity on MRI or disability progression.

CONCLUSIONS

Our findings suggest that peripheral blood lymphocyte changes are not associated with short-term treatment response and with the rate of infections during fingolimod and dimethyl-fumarate treatment in real-world patients. Higher treatment exposure and a lower baseline absolute lymphocyte count are risk factors for lymphopenia development during fingolimod and dimethyl-fumarate therapy.