Immunosuppressants exert differential effects on pan-coronavirus infection and distinct combinatory antiviral activity with molnupiravir and nirmatrelvir.

BACKGROUND: Immunocompromised populations, such as organ transplant recipients and patients with inflammatory bowel disease (IBD) receiving immunosuppressive/immunomodulatory medications, may be more susceptible to coronavirus infections. However, little is known about how immunosuppressants affect coronavirus replication and their combinational effects with antiviral drugs. OBJECTIVE: This study aims to profile the effects of immunosuppressants and the combination of immunosuppressants with oral antiviral drugs molnupiravir and nirmatrelvir on pan-coronavirus infection in cell and human airway organoids (hAOs) culture models. METHODS: Different coronaviruses (including wild type, delta and omicron variants of SARS-CoV-2, and NL63, 229E and OC43 seasonal coronaviruses) were used in lung cell lines and hAOs models. The effects of immunosuppressants were tested. RESULTS: Dexamethasone and 5-aminosalicylic acid moderately stimulated the replication of different coronaviruses. Mycophenolic acid (MPA), 6-thioguanine (6-TG), tofacitinib and filgotinib treatment dose-dependently inhibited viral replication of all tested coronaviruses in both cell lines and hAOs. The half maximum effective concentration (EC50) of tofacitinib against SARS-CoV-2 was 0.62 µM and the half maximum cytotoxic concentration (CC50) was above 30 µM, which resulted in a selective index (SI) of about 50. The anti-coronavirus effect of the JAK inhibitors tofacitinib and filgotinib is dependent on the inhibition of STAT3 phosphorylation. Combinations of MPA, 6-TG, tofacitinib, and filgotinib with the oral antiviral drugs molnupiravir or nirmatrelvir exerted an additive or synergistic antiviral activity. CONCLUSIONS: Different immunosuppressants have distinct effects on coronavirus replication, with 6-TG, MPA, tofacitinib and filgotinib possessing pan-coronavirus antiviral activity. The combinations of MPA, 6-TG, tofacitinib and filgotinib with antiviral drugs exerted an additive or synergistic antiviral activity. Thus, these findings provide an important reference for optimal management of immunocompromised patients infected with coronaviruses.

Molecular and therapeutic insights of rapamycin: a multi-faceted drug from Streptomyces hygroscopicus.

The advancement in pharmaceutical research has led to the discovery and development of new combinatorial life-saving drugs. Rapamycin is a macrolide compound produced from Streptomyces hygroscopicus. Rapamycin and its derivatives are one of the promising sources of drug with broad spectrum applications in the medical field. In recent times, rapamycin has gained significant attention as of its activity against cytokine storm in COVID-19 patients. Rapamycin and its derivatives have more potency when compared to other prevailing drugs. Initially, it has been used exclusively as an anti-fungal drug. Currently rapamycin has been widely used as an immunosuppressant. Rapamycin is a multifaceted drug; it has anti-cancer, anti-viral and anti-aging potentials. Rapamycin has its specific action on mTOR signaling pathway. mTOR has been identified as a key regulator of different pathways. There will be an increased demand for rapamycin, because it has lesser adverse effects when compared to steroids. Currently researchers are focused on the production of effective rapamycin derivatives to combat the growing demand of this wonder drug. The main focus of the current review is to explore the origin, development, molecular mechanistic action, and the current therapeutic aspects of rapamycin. Also, this review article revealed the potential of rapamycin and the progress of rapamycin research. This helps in understanding the exact potency of the drug and could facilitate further studies that could fill in the existing knowledge gaps. The study also gathers significant data pertaining to the gene clusters and biosynthetic pathways involved in the synthesis and production of this multi-faceted drug. In addition, an insight into the mechanism of action of the drug and important derivatives of rapamycin has been expounded. The fillings of the current review, aids in understanding the underlying molecular mechanism, strain improvement, optimization and production of rapamycin derivatives.

Effects of immunophilin inhibitors and non-immunosuppressive analogs on coronavirus replication in human infection models.

Rationale: Human coronaviruses (HCoVs) seriously affect human health by causing respiratory diseases ranging from common colds to severe acute respiratory diseases. Immunophilins, including peptidyl-prolyl isomerases of the FK506-binding protein (FKBP) and the cyclophilin family, are promising targets for pharmaceutical inhibition of coronavirus replication, but cell-type specific effects have not been elucidated. FKBPs and cyclophilins bind the immunosuppressive drugs FK506 and cyclosporine A (CsA), respectively. Methods: Primary human bronchial epithelial cells (phBECs) were treated with CsA, Alisporivir (ALV), FK506, and FK506-derived non-immunosuppressive analogs and infected with HCoV-229E. RNA and protein were assessed by RT-qPCR and immunoblot analysis. Treatment with the same compounds was performed in hepatoma cells (Huh-7.5) infected with HCoV-229E expressing Renilla luciferase (HCoV-229E-RLuc) and the kidney cell line HEK293 transfected with a SARS-CoV-1 replicon expressing Renilla luciferase (SARS-CoV-1-RLuc), followed by quantification of luminescence as a measure of viral replication. Results: Both CsA and ALV robustly inhibited viral replication in all models; both compounds decreased HCoV-229E RNA in phBECs and reduced luminescence in HCoV-229E-RLuc-infected Huh7.5 and SARS-CoV-1-RLuc replicon-transfected HEK293. In contrast, FK506 showed inconsistent and less pronounced effects in phBECs while strongly affecting coronavirus replication in Huh-7.5 and HEK293. Two non-immunosuppressive FK506 analogs had no antiviral effect in any infection model. Conclusion: The immunophilin inhibitors CsA and ALV display robust anti-coronaviral properties in multiple infection models, including phBECs, reflecting a primary site of HCoV infection. In contrast, FK506 displayed cell-type specific effects, strongly affecting CoV replication in Huh7.5 and HEK293, but inconsistently and less pronounced in phBECs.

Antibody response to double SARS-CoV-2 mRNA vaccination in Japanese kidney transplant recipients.

Immunocompromised patients, especially those who undergo kidney transplantation, have lower antibody levels following SARS-CoV-2 mRNA vaccination. The situation of transplant treatment, such as transplant source and immunosuppressive drugs, is different in Japan than that in other countries. Therefore, it is necessary to clarify whether antibody acquisition rates differ between Japan and other countries. This retrospective study included patients with post-kidney transplant who were attending at the Nagoya University Hospital. The anti-SARS-CoV-2 IgG antibody titers were measured between 3 weeks and 3 months after vaccination. Seventy-three patients (45 men and 28 women) were included. Of these, 23 (31.5%) showed antibody presence, and the rates of antibody acquisition were very low than those in the control group (100.0% vs. 31.5%, P < 0.05). Antibody acquisition rates were associated with body mass index (odds ratio [OR]: 1.21, 95% confidence interval [CI]: 1.04-1.39, P < 0.05) and the duration between transplantation and vaccination (OR: 1.01, 95% CI: 1.00-1.02, P < 0.05). The immunosuppressive drugs used were: prednisolone in all cases, tacrolimus in 89.0%, cyclosporine in 9.6%, and mofetil mycophenolate in 97.3%. None of the patients were excluded from receiving two doses of the vaccine due to adverse effects. The study indicated that vaccination-induced antibody acquisition rates against SARS-CoV-2 were extremely low in Japanese patients who underwent post-kidney transplantation. Thus, despite two doses of vaccination, it is necessary to closely monitor infection control in such patients.

Disulfiram-loaded lactoferrin nanoparticles for treating inflammatory diseases.

Sepsis is a dysregulated immune response to infection and potentially leads to life-threatening organ dysfunction, which is often seen in serious Covid-19 patients. Disulfiram (DSF), an old drug that has been used to treat alcohol addiction for decades, has recently been identified as a potent inhibitor of the gasdermin D (GSDMD)-induced pore formation that causes pyroptosis and inflammatory cytokine release. Therefore, DSF represents a promising therapeutic for the treatment of inflammatory disorders. Lactoferrin (LF) is a multifunctional glycoprotein with potent antibacterial and anti-inflammatory activities that acts by neutralizing circulating endotoxins and activating cellular responses. In addition, LF has been well exploited as a drug nanocarrier and targeting ligands. In this study, we developed a DSF-LF nanoparticulate system (DSF-LF NP) for combining the immunosuppressive activities of both DSF and LF. DSF-LF NPs could effectively block pyroptosis and inflammatory cytokine release from macrophages. Treatment with DSF-LF NPs showed remarkable therapeutic effects on lipopolysaccharide (LPS)-induced sepsis. In addition, this therapeutic strategy was also applied to treat ulcerative colitis (UC), and substantial treatment efficacy was achieved in a murine colitis model. The underlying mode of action of these DSF-LF-NPs may contribute to efficiently suppressing macrophage-mediated inflammatory responses and ameliorating the complications caused by sepsis and UC. As macrophage pyroptosis plays a pivotal role in inflammation, this safe and effective biomimetic nanomedicine may offer a versatile therapeutic strategy for treating various inflammatory diseases by repurposing DSF.

Impact of rituximab on COVID-19 outcomes.

Rituximab is associated with prolonged B-cell depletion and secondary hypogammaglobulinemia and is associated with a dampened humoral response and increased infectious complications. To describe the potential impact of prior rituximab therapy on clinical outcomes from SARS-CoV-2 infection and development of COVID-19 antibodies, we conducted a retrospective study of adults across the Mount Sinai Health System diagnosed with COVID-19 who received rituximab for any indication from February 2019 to October 2020. Patients' baseline characteristics, markers of disease severity, clinical outcomes, and antibody development were examined. Of the 49 patients included in the analysis, 63.2% required hospitalization for COVID-19, 24.5% required an ICU admission, and 32.7% died. Proximity of last rituximab infusion and COVID-19 diagnosis did not affect rates of hospitalization, admission to intensive care units or death. Over half (51.7%) of those whose antibodies were checked developed neutralizing anti-spike protein antibodies. The median time between rituximab administration and COVID-19 diagnosis was not significantly different between those who developed antibodies and those who did not (p = .323). Of the 14 patients with documented negative COVID-19 antibody titers, 11 of them survived SARS-CoV-2 infection, indicating that development of neutralizing antibodies may not be necessary for recovery from COVID-19.

Humoral immune response in convalescent COVID-19 people with multiple sclerosis treated with high-efficacy disease-modifying therapies: A multicenter, case-control study.

AIM: To determine the influence of high-efficacy disease modifying therapy (DMT) on the development of IgG SARS-CoV-2 antibody response in COVID-19 convalescent people with multiple sclerosis (pwMS). METHODS: Seventy-four pwMS taking high-efficacy DMTs (specifically natalizumab, fingolimod, alemtuzumab, ocrelizumab, cladribine and ublituximab) and diagnosed with COVID-19 and 44 healthy persons (HC) were enrolled. SARS-CoV2 antibodies were tested with Elecsys® Anti-SARSCoV-2 S assay. RESULTS: pwMS taking high-efficacy DMTs had a significantly higher chance of having negative titer of SARS-CoV2 antibodies compared to healthy controls (33 negative pwMS [44.6%] compared to one negative HC [2.3%], p < 0.001). pwMS taking B-cell depleting therapy (ocrelizumab and ublituximab) had a significantly higher chance of having negative titer of SARS-CoV2 antibodies compared to pwMS on all other DMTs (29 negative pwMS on B-cell therapy [64.4%] compared to four negative pwMS on all other DMTs [13.8%], p < 0.001). Out of other DMTs, two (33.3%) pwMS taking fingolimod and two (16.7%) pwMS taking cladribine failed to develop IgG SARS-COV-2 antibodies. B-cell depleting therapy independently predicted negative titer of IgG SARS-CoV-2 antibody (Exp[B] =0.014, 95%CI 0.002-0.110, p < 0.001). CONCLUSIONS: A significant proportion of convalescent COVID-19 pwMS on high-efficacy DMTs will not develop IgG SARS-CoV-2 antibodies. B-cell depleting therapies independently predict negative and low titer of IgG SARS-CoV-2 antibody.

COVID-19 in Cladribine-treated patient with multiple sclerosis.

Case report describing a patient infected with COVID-19 after initiation of Cladribine, with a favorable disease course and positive seroconversion.

Th17 Cells in Viral Infections-Friend or Foe?

Th17 cells are recognized as indispensable in inducing protective immunity against bacteria and fungi, as they promote the integrity of mucosal epithelial barriers. It is believed that Th17 cells also play a central role in the induction of autoimmune diseases. Recent advances have evaluated Th17 effector functions during viral infections, including their critical role in the production and induction of pro-inflammatory cytokines and in the recruitment and activation of other immune cells. Thus, Th17 is involved in the induction both of pathogenicity and immunoprotective mechanisms seen in the host's immune response against viruses. However, certain Th17 cells can also modulate immune responses, since they can secrete immunosuppressive factors, such as IL-10; these cells are called non-pathogenic Th17 cells. Here, we present a brief review of Th17 cells and highlight their involvement in some virus infections. We cover these notions by highlighting the role of Th17 cells in regulating the protective and pathogenic immune response in the context of viral infections. In addition, we will be describing myocarditis and multiple sclerosis as examples of immune diseases triggered by viral infections, in which we will discuss further the roles of Th17 cells in the induction of tissue damage.

Regulatory T cells and vaccine effectiveness in older adults. Challenges and prospects.

Since the discovery of lymphocytes with immunosuppressive activity, increasing interest has arisen in their possible influence on the immune response induced by vaccines. Regulatory T cells (Tregs) are essential for maintaining peripheral tolerance, preventing autoimmune diseases, and limiting chronic inflammatory diseases. However, they also limit beneficial immune responses by suppressing anti-infectious and anti-tumor immunity. Mounting evidence suggests that Tregs are involved, at least in part, in the low effectiveness of immunization against various diseases where it has been difficult to obtain protective vaccines. Interestingly, increased activity of Tregs is associated with aging, suggesting a key role for these cells in the lower vaccine effectiveness observed in older people. In this review, we analyze the impact of Tregs on vaccination, with a focus on older adults. Finally, we address an overview of current strategies for Tregs modulation with potential application to improve the effectiveness of future vaccines targeting older populations.

Targeting of the CD80/86 proinflammatory axis as a therapeutic strategy to prevent severe COVID-19.

An excessive immune response known as cytokine storm is the hallmark of severe COVID-19. The cause of this cytokine rampage is yet not known. Based on recent epidemiological evidence, we hypothesized that CD80/86 signaling is essential for this hyperinflammation, and that blocking this proinflammatory axis could be an effective therapeutic approach to protect against severe COVID-19. Here we provide exploratory evidence that abatacept, a drug that blocks CD80/86 co-stimulation, produces changes at the systemic level that are highly antagonistic of the proinflammatory processes elicited by COVID-19. Using RNA-seq from blood samples from a longitudinal cohort of n = 38 rheumatic patients treated with abatacept, we determined the immunological processes that are significantly regulated by this treatment. We then analyzed available blood RNA-seq from two COVID19 patient cohorts, a very early cohort from the epicenter of the pandemic in China (n = 3 COVID-19 cases and n = 3 controls), and a recent and larger cohort from the USA (n = 49 severe and n = 51 mild COVD-19 patients). We found a highly significant antagonism between SARS-CoV-2 infection and COVID-19 severity with the systemic response to abatacept. Analysis of previous single-cell RNA-seq data from bronchoalveolar lavage fluid from mild and severe COVID-19 patients and controls, reinforce the implication of the CD80/86 proinflammatory axis. Our functional results further support abatacept as a candidate therapeutic approach to prevent severe COVID-19.

Immunogenicity and Reactogenicity After SARS-CoV-2 mRNA Vaccination in Kidney Transplant Recipients Taking Belatacept.

BACKGROUND: Belatacept may impair humoral immunity, impacting the effectiveness of SARS-CoV-2 mRNA vaccines in transplant recipients. We investigated immunogenicity after SARS-CoV-2 mRNA vaccines in kidney transplant recipients who are and are not taking belatacept. METHODS: Participants were recruited between December 9, 2020, and April 1, 2021. Blood samples were collected after dose 1 and dose 2 (D1, D2) and analyzed using either an anti-SARS-CoV-2 enzyme immunoassay against the S1 domain of the SARS-CoV-2 spike protein or immunoassay against the receptor-binding domain of the SARS-CoV-2 spike protein. Stabilized inverse probability of treatment weights was used to compare immunogenicity, and a weighted logistics regression was used to calculate fold change of positive response. RESULTS: Among the 609 participants studied, 24 (4%) were taking belatacept. After dose 1, 0/24 (0%) belatacept patients had detectable antibodies, compared with 77 of 568 (14%) among the equivalent nonbelatacept population (P = 0.06). After dose 2, 1/19 (5%) belatacept patients had detectable antibodies, compared with 190/381 (50%) among the equivalent nonbelatacept population (P < 0.001). Belatacept use was associated with 16.7-fold lower odds of having a positive post-D2 titer result (P < 0.01). CONCLUSIONS: Additional measures need to be explored to protect kidney transplant recipients taking belatacept. Best safety practices should be continued despite vaccination among this population.

Voclosporin: First Approval.

Voclosporin (Lupkynis™) is an oral calcineurin inhibitor immunosuppressant that is being developed by Aurinia Pharmaceuticals. In January 2021, based on positive results from the pivotal phases II and III trials, oral voclosporin received its first approval in the USA for use in combination with a background immunosuppressive therapy regimen for adults with active lupus nephritis. Voclosporin is also being explored for the novel coronavirus disease 2019 (COVID-19) in kidney transplant recipients. This article summarizes the milestones in the development of voclosporin leading to this first approval for lupus nephritis.

Effect of Calcineurin Inhibitors and Mammalian Target of Rapamycin Inhibitors on the Course of COVID-19 in Kidney Transplant Recipients.

Coronavirus disease 19 (COVID-19) has been an ongoing pandemic since December 2019. Unfortunately, kidney transplant recipients are a high-risk group during the disease course, and scientific data are still limited in this patient group. Beyond the dosage of immunosuppressive drugs, pharmacological immunosuppression may also alter the infection response in the COVID-19 course. The effects of immunosuppressive agents on the development and process of infection should not be decided only by determining how potent they are and how much they suppress the immune system; it is also thought that the direct effect of the virus, increased oxidative stress, and cytokine storm play a role in the pathogenesis of COVID-19 disease. There are data about immunosuppressive drugs like calcineurin inhibitors (CNI) or mammalian target of rapamycin inhibitors (mTORi) therapy related to their beneficial effects during any infection course. Limited data suggest that the use of CNI or mTORi may have beneficial effects on the process. In this hypothetical review, the probable impacts of CNI and mTORi on the pathogenesis of the COVID-19 were investigated.

[Vaccination against SARS-CoV-2 in patients with multiple sclerosis]. / Vacunación frente al SARS-CoV-2 en pacientes con esclerosis múltiple.

INTRODUCTION: The recent availability of SARS-CoV-2 vaccines has raised concerns in certain patient groups, such as those with multiple sclerosis. However, there are currently few publications that provide information on this issue. We pooled the information available on the safety and efficacy of vaccination against SARS-CoV-2 in patients with multiple sclerosis, with and without disease-modifying therapy. DEVELOPMENT: The study consisted in a literature search focused on the types of SARS-CoV-2 vaccines, the current status of their approval, and the data available on the safety and efficacy of vaccines in patients with multiple sclerosis, including the new COVID-19 vaccines. Based on this search, the document has been designed taking into account current evidence and expert recommendations. There are no data on the safety and efficacy of SARS-CoV-2 vaccines in patients with multiple sclerosis. However, evidence does exist to suggest that messenger RNA (mRNA) vaccines against SARS-CoV-2 are as safe in these patients as in other individuals. Some therapies with immunosuppressants might reduce the effectiveness of these vaccines and require the scheduling of their administration, preferably before the start of treatment if possible. CONCLUSION: The data available make it possible to recommend mRNA vaccines against SARS-CoV-2 in patients with multiple sclerosis. In patients on fingolimod, cladribine, alemtuzumab, ocrelizumab and rituximab, vaccination prior to the initiation of medication administration would be recommendable whenever possible.

TITLE: Vacunación frente al SARS-CoV-2 en pacientes con esclerosis múltiple.Introducción. La reciente disponibilidad de vacunas contra el SARS-CoV-2 ha suscitado dudas en determinados colectivos de pacientes, como los que padecen esclerosis múltiple. Sin embargo, en la actualidad hay pocas publicaciones que ofrezcan información en este sentido. Se recopila la información disponible sobre la seguridad y la eficacia de la vacunación contra el SARS-CoV-2 en pacientes con esclerosis múltiple, con y sin tratamiento modificador de la enfermedad. Desarrollo. Búsqueda bibliográfica enfocada en los tipos de vacunas contra el SARS-CoV-2, la situación actual de su aprobación, y los datos disponibles sobre la eficacia y la seguridad de las vacunas en pacientes con esclerosis múltiple, incluidas las nuevas vacunas frente a la COVID-19. A partir de esta búsqueda, se ha diseñado el documento recogiendo la evidencia actual y las recomendaciones de expertos. No existen datos sobre la seguridad y la eficacia de las vacunas contra el SARS-CoV-2 en pacientes con esclerosis múltiple. Sin embargo, los datos disponibles permiten prever que las vacunas de tipo ARN mensajero (ARNm) frente al SARS-CoV-2 son tan seguras en ellos como en el resto de los individuos. Algunos de los tratamientos inmunosupresores podrían reducir la efectividad de las vacunas y requerir la planificación del momento de su administración, preferentemente antes del inicio del tratamiento en caso de ser posible. Conclusión. Los datos disponibles permiten recomendar las vacunas de tipo ARNm frente al SARS-CoV-2 en los pacientes con esclerosis múltiple. En los pacientes con fingolimod, cladribina, alemtuzumab, ocrelizumab y rituximab, sería recomendable la vacunación previa al inicio de la medicación cuando sea posible.

Simultaneous Inhibition of SARS-CoV-2 Entry Pathways by Cyclosporine.

The COVID-19 pandemic caused by SARS-CoV-2 represents a global public health emergency. The entry of SARS-CoV-2 into host cells requires the activation of its spike protein by host cell proteases. The serine protease, TMPRSS2, and cysteine proteases, Cathepsins B/L, activate spike protein and enable SARS-CoV-2 entry to the host cell through two completely different and independent pathways. Therefore, inhibiting either TMPRSS2 or cathepsin B/L may not sufficiently block the virus entry. We here hypothesized that simultaneous targeting of both the entry pathways would be more efficient to block the virus entry rather than targeting the entry pathways individually. To this end, we utilized the network-based drug repurposing analyses to identify the possible common drugs that can target both the entry pathways. This study, for the first time, reports the molecules like cyclosporine, calcitriol, and estradiol as candidate drugs with the binding ability to the host proteases, TMPRSS2, and cathepsin B/L. Next, we analyzed drug-gene and gene-gene interaction networks using 332 human targets of SARS-CoV-2 proteins. The network results indicate that, out of 332 human proteins, cyclosporine interacts with 216 (65%) proteins. Furthermore, we performed molecular docking and all-atom molecular dynamics (MD) simulations to explore the binding of drug with TMPRSS2 and cathepsin L. The molecular docking and MD simulation results showed strong and stable binding of cyclosporine A (CsA) with TMPRSS2 and CTSL genes. The above results indicate cyclosporine as a potential drug molecule, as apart from interacting with SARS-CoV-2 entry receptors, it also interacts with most of SARS-CoV-2 target host genes; thus it could potentially interfere with functions of SARS-CoV-2 proteins in human cells. We here also suggest that these antiviral drugs alone or in combination can simultaneously target both the entry pathways and thus can be considered as a potential treatment option for COVID-19.

COVID-19 and inflammatory bowel disease: A pathophysiological assessment.

Coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, has led to the ongoing global pandemic. Although most patients experience no or only mild symptoms, some patients can develop severe illness, such as progressive pneumonia, acute respiratory distress syndrome, secondary hemophagocytic lymphohistiocytosis and multiple organ failure caused by cytokine release syndrome. A majority of COVID-19 patients also develop gastrointestinal symptoms. These can present special challenges to the management of patients with inflammatory bowel disease (IBD) due to potential interactions between the immune response related to SARS-CoV-2 infection and dysregulated immunity associated with IBD. In this context, the pathogenesis of COVID-19 is reviewed in order to address these questions regarding immune interactions between COVID-19 and IBD.

SARS-CoV-2/COVID-19 in multiple sclerosis patients receiving disease-modifying therapy.

At the end of 2019, the COVID-19 pandemic began, which at the time of writing continues to be a serious problem for many areas of medicine, including neurology. Since patients with multiple sclerosis (MS) often exhibit motor disability and receive disease-modifying therapy (DMT), which has an immunosuppressive effect, it is plausible that this will affect the susceptibility of MS patients to COVID-19, as well as the course of this disease. However, current data indicate that the use of DMT does not cause negative prognosis in COVID-19 sufferers, but the motor disability progression associated with MS does. In this study, we present the case reports of 4 patients with relapsing-remitting MS, who developed COVID-19, and despite the use of DMT the course of the disease was mild. Two patients were treated with dimethyl fumarate, one with Interferon ß1b and one with glatiramer acetate. One of the patients using dimethyl fumarate had lymphopenia. All patients had symptoms of COVID-19 from the nervous system, the most frequent being headache, which occurred in all patients. The aim of this article is to present a case series of four patients with MS and COVID-19, and to discuss the available literature on COVID-19 in patients with MS, with particular consideration of the impact of DMT.