Predictors of lymphocyte count recovery after dimethyl fumarate-induced lymphopenia in people with multiple sclerosis

Bariatric surgery and dimethyl fumarate-induced lymphopenia in patients with multiple sclerosis

INTRODUCTION

Lymphopenia is a known side effect of dimethyl fumarate (DMF), a disease-modifying therapy (DMT) for patients with multiple sclerosis (pwMS). A body mass index ≥ 30 kg/m2 has been identified as a protective factor; however, no data are available on lymphopenia in pwMS undergoing to weight loss due to bariatric surgery.

METHODS

We described two pwMS with history of bariatric surgery who started DMF as DMT.

RESULTS

The two pwMS experienced persistent lymphopenia during DMF-treatment, which was resolved after its discontinuation.

CONCLUSIONS

Several mechanisms might modify DMF pharmacokinetic profiles after bariatric surgery and its bioavailability. Absolute lymphocyte count should be monitored in pwMS treated with DMF and history of bariatric surgery and weight loss.

Frequency of Dimethyl Fumarate-Induced Lymphopenia among Omani Patients with Multiple Sclerosis

Objectives

Dimethyl fumarate (DMF) is known to cause lymphopenia when used to treat patients with multiple sclerosis (MS). However, research on DMF therapy in the Arab world, especially in Oman, is scarce. This study aimed to analyse the prevalence of lymphopenia among Omani patients with MS and their reasons for discontinuing DMF therapy.

Methods

In this retrospective study, the medical records of Omani patients with MS who were treated using DMF at two tertiary hospitals in Muscat, Oman, from February 2017 to February 2023 were reviewed. Their demographic, clinical and laboratory data were retrieved and analysed. Absolute lymphocyte count values at baseline and at the last follow-up, as well as the reasons for discontinuing DMF therapy, were collected. Descriptive and inferential statistical techniques were used for data analysis. Binary-logistic regression analysis was used to identify the risk factors for DMF-induced lymphopenia.

Results

A total of 64 Omani patients with MS were included in this study. The majority of the study participants (n = 40; 63%) were female. All included patients started DMF therapy at the mean age of 33 ± 7.7 years. After administration of DMF, 14 (21.9%) patients developed grades 1-3 of lymphopenia. The DMF therapy was discontinued for 23 (36.0%) patients, mainly in response to adverse events or confirmed pregnancy. Female gender was the only significant predictor of DMF-induced lymphopenia (P = 0.037).

Conclusions

Most Omani patients with MS had mild lymphopenia (grades 1-2). Early adverse events and pregnancy were the main reasons provided for discontinuing DMF therapy.

Clinical use of dimethyl fumarate in multiple sclerosis treatment: an update to include China, using a modified Delphi method

Dimethyl fumarate (DMF) is a widely used oral disease-modifying therapy for multiple sclerosis (MS). Its efficacy and safety profiles are supported by over a decade of experience. Differences exist between Asia and Europe/United States in the prevalence and characteristics of MS; most data for DMF are derived from populations outside Asia. DMF was recently (2021) approved for use in China. The objectives of this review were to evaluate the evidence for DMF's profile, to provide an update to healthcare providers on current knowledge surrounding its use and to assess the relevance of existing data to use in China. This study used a modified Delphi method based on the insights of a scientific Steering Committee (SC), with a structured literature review conducted to assess the data of DMF. The literature review covered all papers in English (from 01 January 2011 to 21 February 2022) that include 'dimethyl fumarate' and 'multiple sclerosis', and their MeSH terms, on PubMed, supplemented by EMBASE and Citeline searches. Papers were categorized by topic and assessed for relevance and quality, before being used to formulate statements summarizing the literature on each subject. SC members voted on/revised statements, requiring ⩾80% agreement and ⩽10% disagreement for inclusion. Statements not reaching this level were discussed further until agreement was reached or until there was agreement to remove the statement. A total of 1030 papers were retrieved and used to formulate the statements and evidence summaries considered by the SC members. A total of 45 statements were agreed by the SC members. The findings support the positive efficacy and safety profile of DMF in treating patients with MS. Limited Chinese patient data are an ongoing consideration; however, based on current evidence, the statements are considered applicable to both the global and Chinese populations. DMF is a valuable addition to address unmet MS treatment needs in China. Registration: Not applicable.

Mechanism of action and therapeutic potential of dimethyl fumarate in ischemic stroke

Dimethyl fumarate (DMF) is an immunomodulatory drug currently approved for the treatment of multiple sclerosis and psoriasis. Its benefits on ischemic stroke outcomes have recently come to attention. To date, only tissue plasminogen activators (tPAs) and clot retrieval methods have been approved by the FDA for the treatment of ischemic stroke. Ischemic conditions lead to inflammation through diverse mechanisms, and recanalization can worsen the state. DMF and the nuclear factor erythroid-derived 2-related factor 2 (Nrf2) pathway it regulates seem to be important in postischemic inflammation, and animal studies have demonstrated that the drug improves overall stroke outcomes. Although the exact mechanism is still unknown, studies indicate that these beneficial impacts are due to the modulation of immune responses, blood-brain barrier permeability, and hemodynamic adjustments. One major component evaluated before, during, and after tPA therapy in stroke patients is blood pressure (BP). Recent studies have found that DMF may impact BP. Both hypotension and hypertension need correction before treatment, which may delay the appropriate intervention. Since BP management is crucial in managing stroke patients, it is important to consider DMF's role in this matter. That being said, it seems further investigations on DMF may lead to an alternative approach for stroke patients. In this article, we discuss the mechanistic roles of DMF and its potential role in stroke based on previously published literature and laboratory findings.

Simple Parameters from Complete Blood Count Predict Lymphopenia, Adverse Effects and Efficacy in People with MS treated with Dimethyl Fumarate

BACKGROUND

Dimethyl fumarate (DMF) is a first-line oral therapy for relapsing-remitting multiple sclerosis (RRMS). This retrospective study aims to determine the utility of routine complete blood counts (CBC) in predicting lymphopenia, adverse effects and efficacy in a real-world clinical setting.

METHODS

The Calgary Multiple Sclerosis (MS) Clinic manages over 1800 people with MS on disease-modifying therapies (DMT). Data of patients with relapsing-remitting MS (pwMS) who initiated DMF between July 1, 2013 and December 31, 2014 were included. Patients were followed for one year. DMT use is carefully monitored and pwMS need a screening CBC and have regular CBCs done at follow-up. Demographic, clinical, MRI and relapse information are collected prospectively in a clinic database. We analyzed CBCs at baseline and month 3.

RESULTS

We identified 139 pwMS in the study period who started DMF. Median follow-up time on-drug was 12 (0.16-12) months. In our study, 15.8% of pwMS developed lymphopenia grade 2 or higher. Baseline lymphocyte counts and older age were significant predictors of lymphopenia. Higher baseline eosinophil counts predicted flushing/gastrointestinal adverse effects, and higher baseline monocyte counts were predictive of breakthrough disease activity. Neutrophil and platelet to lymphocyte ratios, markers that have been associated with overall mortality in the general population, were increased at month 3.

CONCLUSIONS

Routinely obtained CBCs during the screening and monitoring of people with MS starting DMF offer clinically useful information and generate interesting hypotheses. Age and baseline lymphocyte counts are reinforced as clinically useful predictors of lymphopenia. Our novel findings that baseline eosinophil and monocyte counts could offer insights into usual adverse effects and efficacy, respectively, should be further investigated as a potentially new set of biomarkers.

New and Old Horizons for an Ancient Drug: Pharmacokinetics, Pharmacodynamics, and Clinical Perspectives of Dimethyl Fumarate

(1) Background: In their 60-year history, dimethyl fumarate and other salts of fumaric acid have been used for the treatment of psoriasis and other immune-mediated diseases for their immune-modulating properties. Over the years, new mechanisms of action have been discovered for this evergreen drug that remains a first-line treatment for several different inflammatory diseases. Due to its pleiotropic effects, this molecule is still of great interest in varied conditions, not exclusively inflammatory diseases. (2) Methods: The PubMed database was searched using combinations of the following keywords: dimethyl fumarate, pharmacokinetics, pharmacodynamics, adverse effects, psoriasis, multiple sclerosis, and clinical indications. This article reviews and updates the pharmacokinetics, mechanisms of action, and clinical indications of dimethyl fumarate. (3) Conclusions: The pharmacology of dimethyl fumarate is complex, fascinating, and not fully known. Progressive insights into the molecule's mechanisms of action will make it possible to maximize its clinical efficacy, reduce concerns about adverse effects, and find other possible areas of application.

Gut microbiota composition as a candidate risk factor for dimethyl fumarate-induced lymphopenia in multiple sclerosis

Mounting evidence points towards a pivotal role of gut microbiota in multiple sclerosis (MS) pathophysiology. Yet, whether disease-modifying treatments alter microbiota composition and whether microbiota shape treatment response and side-effects remain unclear. In this prospective observational pilot study, we assessed the effect of dimethyl fumarate (DMF) on gut microbiota and on host/microbial metabolomics in a cohort of 20 MS patients. Combining state-of-the-art microbial sequencing, metabolome mass spectrometry, and computational analysis, we identified longitudinal changes in gut microbiota composition under DMF-treatment and an increase in citric acid cycle metabolites. Notably, DMF-induced lymphopenia, a clinically relevant safety concern, was correlated with distinct baseline microbiome signatures in MS patients. We identified gastrointestinal microbiota as a key therapeutic target for metabolic properties of DMF. By characterizing gut microbial composition as a candidate risk factor for DMF-induced lymphopenia, we provide novel insights into the role of microbiota in mediating clinical side-effects.

Influence of Previous Disease-Modifying Drug Exposure on T-Lymphocyte Dynamic in Patients With Multiple Sclerosis Treated With Ocrelizumab

Background and Objectives

To investigate the longitudinal dynamic of lymphocyte subsets during treatment with ocrelizumab (OCR) in patients with multiple sclerosis (PwMS).

Methods

A multicenter retrospective study was conducted in 161 PwMS starting treatment with OCR grouped in naive (naive, n = 40), switching from fingolimod (FTY, n = 52), and switching from other immunomodulating drugs (other, n = 69). Mean lymphocyte subset (total, CD3+, CD4+, CD8+, CD20+, and natural killer) counts were analyzed at baseline, 6 months, and 12 months. Rate of lymphocytopenia for each subset was calculated at all time points in all groups.

Results

Mean total, CD3+, and CD4+ counts were significantly different among groups (p < 0.001) at all time points, whereas CD8+ and CD20+ counts only at baseline (p = 0.0157; p < 0.001), consistently lower in FTY. After adjustment for baseline values, interaction time*group was not statistically significant (p > 0.05 for each subset). The odds of lymphopenia were significantly higher among FTY patients compared with naive for total, CD3+, CD4+, and CD20+ cells at baseline, for total and CD4+ cells at the sixth month, and for total cells at the 12th month.

Discussion

OCR per se exerts a modest depleting effect on T cells that seems rather due to a carryover phenomenon of previous therapies, particularly FTY. These data may help in the overall evaluation of the risk/benefit profile of treatment sequencing.

Lymphopenia during treatment with dimethyl fumarate in patients with multiple sclerosis: Prevalence, predicting factors and clinical outcomes

BACKGROUND

Lymphopenia is a common side effect of treatment with dimethyl fumarate (DMF) in patients with multiple sclerosis (PwMS). Prevalence and predictive factors of this side effect are still uncertain, because literature has provided discrepant results and it is still a matter of debate if lymphopenia is associated with a better treatment outcome.

METHODS

We retrospectively recruited PwMS treated for at least one month with DMF and collected clinical, demographic data and absolute lymphocyte count (ALC) during follow-up. Lymphopenia was graded according to CTCAE. Patients according to the grade in lymphopenia (all grades) and severe lymphopenia (grade II-IV). To evaluate predictors of lymphopenia, we compared characteristics of patients with/without lymphopenia and patients with/without severe lymphopenia. A logistic binary regression was performed to elucidate any predictive factor of lymphopenia and severe lymphopenia. Area under the curve (AUC) was calculated to evaluate sensibility and specificity of predictors. We analyzed treatment outcome with NEDA-3 status at 1- and 2-years.

RESULTS

98 of 105 patients treated with DMF were included. 46.9% developed lymphopenia, 27.6% severe lymphopenia. Lymphopenia was associated with basal ALC (p<0.001, AUC=0.786), treatment duration (p = 0.01, AUC=0.685),% of reduction at third month (p = 0.001, AUC=0.616) Severe lymphopenia was associated with basal ALC (p = 0.003, AUC=0.750).NEDA-3 status at 1-year (n = 66) and at 2-year (n = 44) did not differ in patients with/without lymphopenia (p = 0.059; p = 0.583) or with/without severe lymphopenia (p = 1.02; p = 0.169).

CONCLUSION

Lymphopenia is a common side effect of DMF and basal ALC predicts its development. Lymphopenia is not associated with the achievement of NEDA-3 status.

Incidence of persistent lymphopenia in people with multiple sclerosis on dimethyl fumarate

BACKGROUND

Dimethyl fumarate (DMF) is a disease modifying therapy (DMT) used in the management of Multiple Sclerosis (MS). Lymphopenia occurs in approximately 30% of people receiving this medication. The recently revised Summary of Product Characteristics (SPC) recommends increased monitoring or cessation of this medication in the context of persistent lymphopenia, because of an increased risk of progressive multifocal leukoencephalopathy (PML). It is therefore important for clinicians and patients to be aware of the frequency of persistent, moderate-severe lymphopenia in order to make informed decisions regarding drug choice and safety monitoring.

METHODS

We reviewed medical records of 156 people with MS (PwMS) started on DMF between 2014 and 2020, who received at least 6 months of treatment, in order to identify the incidence and duration of persistent lymphopenia.

RESULT

Ten were excluded due to missing data. In 146 patients, treated for 30.7 months (mean), 16 (11%) were found to experience persistent moderate lymphopenia (0.5-0.7 × 10⁹/L) and 5 (3%) experienced persistent severe lymphopenia (<0.5 × 10⁹/L). Of the 5 patients with persistent severe lymphopenia, 3 discontinued DMF. Two cases stopped directly due to SPC recommendations and after 6-months no further DMTs were initiated. Treatment was withdrawn in a further case due to lack of efficacy. Two cases remained on DMF as their persistent severe lymphopenia predated SPC revision. Mean times to persistent moderate and severe lymphopenia were 10.6 months and 25.5 months respectively. Increased age was a predictor for persistent lymphopenia (B = 0.071, p = 0.004) while sex, and previous DMT were not.

The Dimethyl Fumarate Experience: A Handy Drug With Broad Clinical Utility

Objectives: The aim of this study was to characterize multiple sclerosis (MS) patients exposed to dimethyl fumarate (DMF) and to evaluate the predictors of therapeutic response. In addition, the study offers a picture of how DMF use has changed over the past few years in naive or switcher patients.

Methods: In this observational monocentric study, we examined the prescription flow of DMF in MS patients categorized as naive or switchers (for safety/tolerability, ineffectiveness, and de-escalation strategy) from 2015 to 2019. Clinical and magnetic resonance imaging data of DMF-treated patients were analyzed, and NEDA-3 status at 24 months was evaluated by the three assessment components (absence of clinical relapses, no Expanded Disability Status Scale progression, no radiological activity). Determinants of therapeutic response were also evaluated using regression analysis.

Results: The sample included 595 MS patients exposed to DMF categorized as naive (158; 26.5%) and switchers for reasons of safety/tolerability (198; 33.3%), inefficacy (175; 29.4%), and de-escalation strategy (64; 10.8%). A 15% increase in DMF use in naive and horizontal shift groups was observed in the last 3 years of observation, whereas there was a drop, with prescription passed from ~20% to <5%, as an exit strategy from second-line therapies. NEDA-3 status was calculated for 340 patients after 24 months of DMF treatment and achieved in 188 (55.3%) of these. Analyzing the predictors of DMF response, we observed that lower annualized relapse rate (ARR) in 2 years pretreatment [hazard ratio (HR) = 0.49, p = 0.001] and being naive patients (HR = 1.38, p = 0.035) were associated with achievement of NEDA-3. Analogously, ARR in 2 years pretreatment affected the NEDA-3 achievement at 24 months in patients of the de-escalation group (HR = 0.07, p = 0.041), also indicating an effect related to the DMF initiation within 3 months (HR = 1.24, p = 0.029).

Conclusion: Our findings confirm DMF as a handy drug with broad clinical utility, with greater benefits for naive patients and horizontal switchers. Additionally, an increase in the flow of DMF prescriptions in these two groups of patients was also observed in our cohort.

Persisting lymphopenia and dimethyl fumarate: A clinical commentary

Severe prolonged lymphopenia as rare side-effect of dimethyl fumarate is mostly reversible. Caldito et al. report a case of persistent severe lymphopenia over 5 years after discontinuation of dimethyl fumarate. We discuss several clinical implications. Safe withdrawal of disease modifying therapies in terms of reoccurrence of disease activity and drug related adverse events need further attention as our treatment armamentarium continues to grow.