Safety and in vivo immune assessment of escalating doses of oral laquinimod in patients with RRMS

Background Laquinimod is an oral immunomodulator in clinical development to treat relapsing-remitting multiple sclerosis (RRMS). Laquinimod is in clinical development for the treatment of multiple sclerosis and Huntington Disease (HD). The objective of this study is to assess the safety, tolerability, pharmacokinetics (PK) and cytoimmunologic effects following escalating doses of laquinimod in patients with RRMS. Methods One hundred twelve patients were randomly assigned to laquinimod/placebo in a series of separate dose- escalating cohorts starting from a daily oral dose of 0.9 mg/1.2 mg escalating to 2.7 mg, in 0.3 mg increments. Results Twenty-eight patients received placebo and 84 received laquinimod ranging from 0.9 to 2.7 mg. No deaths occurred. One serious adverse event (SAE) of perichondritis was reported, which was unrelated to laquinimod (0.9 mg). There was no increased incidence of adverse events (AEs) with escalating doses. Laquinimod-treated patients showed more abnormal laboratory levels in liver enzymes, P-amylase, C-reactive protein (CRP), and fibrinogen, but most shifts were clinically non- significant. The exposure of laquinimod was dose proportional and linear in the tested dose range. An immunological substudy showed significant dose- dependent decreases in 6-sulpho LacNAc + dendritic cell (slanDC) frequency following laquinimod compared to placebo. Conclusion Laquinimod doses up to 2.7 mg were safely administered to patients with RRMS. An in vivo effect of laquinimod on the innate immune system was demonstrated. Trial registration EudraCT Number: 2009-011234-99. Registered 23 June 2009

New insights into the pharmacokinetics and pharmacodynamics of natalizumab treatment for patients with multiple sclerosis, obtained from clinical and in vitro studies

Background The monoclonal antibody natalizumab (NAT) inhibits the migration of lymphocytes throughout the blood–brain barrier by blocking very late antigen (VLA)-4 interactions, thereby reducing inflammatory central nervous system (CNS) activity in patients with multiple sclerosis (MS). We evaluated the effects of different NAT treatment regimens. Methods We developed and optimised a NAT assay to measure free NAT, cell-bound NAT and VLA-4 expression levels in blood and cerebrospinal fluid (CSF) of patients using standard and prolonged treatment intervals and after the cessation of therapy. Results In paired CSF and blood samples of NAT-treated MS patients, NAT concentrations in CSF were approximately 100-fold lower than those in serum. Cell-bound NAT and mean VLA-4 expression levels in CSF were comparable with those in blood. After the cessation of therapy, the kinetics of free NAT, cell-bound NAT and VLA-4 expression levels differed. Prolonged intervals greater than 4 weeks between infusions caused a gradual reduction of free and cell-bound NAT concentrations. Sera from patients with and without NAT-neutralising antibodies could be identified in a blinded assessment. The NAT-neutralising antibodies removed NAT from the cell surface in vivo and in vitro. Intercellular NAT exchange was detected in vitro. Conclusions Incorporating assays to measure free and cell-bound NAT into clinical practice can help to determine the optimal individual NAT dosing regimen for patients with MS

Letter to the editor on the paper: “The majority of natalizumab-treated MS patients have high natalizumab concentrations at time of re-dosing”

Van Kempen et al. described high natalizumab concentrations in their natalizumab-treated multiple sclerosis (MS) patients at time of re-dosing. Based on the literature research the authors consider a natalizumab concentration above 2 μg/mL to be sufficient for an adequate alpha-4 integrin receptor saturation of above 70%. Recently, we have demonstrated similar results using our new cell-based immunoassay to evaluate free natalizumab concentration, cell-bound natalizumab, and alpha-4 integrin receptor saturation as the key pharmacokinetic/pharmacodynamic parameters of natalizumab treatment in different in vivo settings. We investigated the effects of treatment interval extension or treatment cessation

Fingolimod additionally acts as immunomodulator focused on the innate immune system beyond its prominent effects on lymphocyte recirculation

Background Growing evidence emphasizes the relevance of sphingolipids for metabolism and immunity of antigen-presenting cells (APC). APCs are key players in balancing tolerogenic and encephalitogenic responses in immunology. In contrast to the well-known prominent effects of sphingosine-1-phosphate (S1P) on lymphocyte trafficking, modulatory effects on APCs have not been fully characterized. Methods Frequencies and activation profiles of dendritic cell (DC) subtypes, monocytes, and T cell subsets in 35 multiple sclerosis (MS) patients were evaluated prior and after undergoing fingolimod treatment for up to 24 months. Impact of fingolimod and S1P on maturation and activation profile, pro-inflammatory cytokine release, and phagocytotic capacity was assessed in vitro and ex vivo. Modulation of DC-dependent programming of naïve CD4+ T cells, as well as CD4+ and CD8+ T cell proliferation, was also investigated in vitro and ex vivo. Results Fingolimod increased peripheral slanDC count—CD1+ DC, and monocyte frequencies remained stable. While CD4+ T cell count decreased, ratio of Treg/Th17 significantly increased in fingolimod-treated patients over time. CD83, CD150, and HLADR were all inhibited, but CD86 was upregulated in DCs after incubation in the presence of fingolimod. Fingolimod but not S1P was associated with reduced release of pro-inflammatory cytokines from DCs and monocytes in vitro and ex vivo. Fingolimod also inhibited phagocytic capacity of slanDCs and monocytes. After fingolimod, slanDCs demonstrated reduced potential to induce interferon–gamma-expressing Th1 or IL-17-expressing Th17 cells and DC-dependent T cell proliferation in vitro and in fingolimod-treated patients. Conclusions We present the first evidence that S1P-directed therapies can act additionally as immunomodulators that decrease the pro-inflammatory capabilities of APCs, which is a crucial element in DC-dependent T cell activation and programming

Safety and in vivo immune assessment of escalating doses of oral laquinimod in patients with RRMS

Abstract Background Laquinimod is an oral immunomodulator in clinical development to treat relapsing-remitting multiple sclerosis (RRMS). Laquinimod is in clinical development for the treatment of multiple sclerosis and Huntington Disease (HD). The objective of this study is to assess the safety, tolerability, pharmacokinetics (PK) and cytoimmunologic effects following escalating doses of laquinimod in patients with RRMS. Methods One hundred twelve patients were randomly assigned to laquinimod/placebo in a series of separate dose-escalating cohorts starting from a daily oral dose of 0.9 mg/1.2 mg escalating to 2.7 mg, in 0.3 mg increments. Results Twenty-eight patients received placebo and 84 received laquinimod ranging from 0.9 to 2.7 mg. No deaths occurred. One serious adverse event (SAE) of perichondritis was reported, which was unrelated to laquinimod (0.9 mg). There was no increased incidence of adverse events (AEs) with escalating doses. Laquinimod-treated patients showed more abnormal laboratory levels in liver enzymes, P-amylase, C-reactive protein (CRP), and fibrinogen, but most shifts were clinically non-significant. The exposure of laquinimod was dose proportional and linear in the tested dose range. An immunological substudy showed significant dose-dependent decreases in 6-sulpho LacNAc + dendritic cell (slanDC) frequency following laquinimod compared to placebo. Conclusion Laquinimod doses up to 2.7 mg were safely administered to patients with RRMS. An in vivo effect of laquinimod on the innate immune system was demonstrated. Trial registration EudraCT Number: 2009-011234-99 . Registered 23 June 2009

Additional file 1: Figure S1. of Safety and in vivo immune assessment of escalating doses of oral laquinimod in patients with RRMS

Study MS-LAQ-101 flow chart. Figure S2. Average plasma concentrations of laquinimod on Day 21 after repeated daily administration. Figure S3. Exposure-dose plots of laquinimod after multiple dose administration. Table S1. Distribution of study drug termination reasons. Table S2. Biochemistry shift analysis to abnormal levels. Table S3. Hematology shift analysis. (DOCX 276 kb