Safety and efficacy of amlitelimab, a fully human nondepleting, noncytotoxic anti-OX40 ligand monoclonal antibody, in atopic dermatitis: results of a phase IIa randomized placebo-controlled trial

Background Atopic dermatitis (AD) is an inflammatory skin disease with significant unmet need. Blockade of the OX40–OX40 ligand (OX40L) costimulation pathway by targeting OX40L on antigen-presenting cells (APCs) with a fully human noncytotoxic, nondepleting anti-OX40L monoclonal antibody (amlitelimab; SAR445229; KY1005) is a novel way to modulate persistent inflammation. Objectives To assess the safety and efficacy of amlitelimab over 16 weeks in adults with AD in a phase IIa double-blind placebo-controlled study. Methods The study was conducted at 19 hospitals in Germany, Poland, Spain and the UK. Eligible patients with moderate-to-severe AD were randomized (1 : 1 : 1) to low-dose intravenous (IV) amlitelimab (200 mg), high-dose IV amlitelimab (500 mg) or placebo, followed by three maintenance doses (50% of loading dose) at 4, 8 and 12 weeks, with safety follow-up to week 36. The co-primary endpoints were the incidence of treatment-emergent adverse events (all patients who received ≥ 1 dose of the study drug) and mean percentage change in Eczema Area and Severity Index (EASI) to week 16 (full analysis set). Results Between 13 December 2018 and 12 May 2020, 89 patients were randomly assigned to low- (n = 29) or high-dose amlitelimab (n = 30) or placebo (n = 29), of whom 88 proceeded to treatment [37 women (42%), 51 (58%) men; mean (SD) age 33.6 (11.9) years]. Amlitelimab was generally well tolerated with an unremarkable safety profile; no hypersensitivity events were reported. For the primary endpoint, the least square mean percentage change in EASI from baseline to week 16 was –80.12% [95% confidence interval (CI) –95.55 to –64.68; P = 0.009 vs. placebo] and –69.97% (95% CI –85.04 to –54.60; P = 0.07 vs. placebo) for the low- (n = 27) and high-dose (n = 27) amlitelimab groups, respectively, vs. –49.37% (95% CI –66.02 to –32.72) for placebo (n = 24). Numerically greater reductions in EASI were observed for amlitelimab vs. placebo from weeks 2 to 16. Conclusions Novel targeting of OX40L-expressing APCs with amlitelimab was well tolerated and resulted in clinically meaningful improvements in AD

OX40L Inhibition suppresses KLH-driven immune responses in healthy volunteers: a randomized controlled trial demonstrating proof-of-pharmacology for KY1005

The safety, tolerability, immunogenicity, and pharmacokinetic (PK) profile of an anti-OX40L monoclonal antibody (KY1005, currently amlitelimab) were evaluated. Pharmacodynamic (PD) effects were explored using keyhole limpet hemocyanin (KLH) and tetanus toxoid (TT) immunizations. Sixty-four healthy male subjects (26.5 +/- 6.0 years) were randomized to single doses of 0.006, 0.018, or 0.05 mg/kg, or multiple doses of 0.15, 0.45, 1.35, 4, or 12 mg/kg KY1005, or placebo (6:2). Serum KY1005 concentrations were measured. Antibody responses upon KLH and TT immunizations and skin response upon intradermal KLH administration were performed. PD data were analyzed using repeated measures analysis of covariances (ANCOVAs) and post hoc exposure-response modeling. No serious adverse events occurred and all adverse events were temporary and of mild or moderate severity. A nonlinear increase in mean serum KY1005 concentrations was observed (median time to maximum concentration (T-max) similar to 4 hours, geometric mean terminal half-life (t1/2) similar to 24 days). Cutaneous blood perfusion (estimated difference (ED) -13.4 arbitrary unit (AU), 95% confidence interval (CI) -23.0 AU to -3.8 AU) and erythema quantified as average redness (ED -0.23 AU, 95% CI -0.35 AU to -0.11 AU) decreased after KY1005 treatment at doses of 0.45 mg/kg and above. Exposure-response analysis displayed a statistically significant treatment effect on anti-KLH antibody titers (IgG maximum effect (E-max) -0.58 AU, 95% CI -1.10 AU to -0.06 AU) and skin response (erythema E-max -0.20 AU, 95% CI -0.29 AU to -0.11 AU). Administration of KY1005 demonstrated an acceptable safety and tolerability profile and PK analyses displayed a nonlinear profile of KY1005. Despite the observed variability, skin challenge response after KY1005 treatment indicated pharmacological activity of KY1005. Therefore, KY1005 shows potential as a novel pharmacological treatment in immune-mediated disorders.Drug Delivery Technolog

Mechanisms of activation of self-reactive T cells

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN023972 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Comparison of peptide and superantigen-induced anergy in a peptide-specific polyclonal human T cell line.

T cells recognizing tetanus toxin peptide 'p2' (sequence 830-844) raised in HLA DR6 individuals preferentially express V beta 2 in the TCR. A p2-specific T cell line (60% V beta 2+) was used to compare peptide and superantigen [toxic shock syndrome toxin-1 (TSST-1)]-induced clonal anergy. Many experiments consistently revealed that the degree of 'tolerance' or 'clonal anergy' induced by peptide was greater than with the superantigen TSST-1. These results are of interest in a number of contexts. First they suggest that using superantigens or anti-V beta to delete the majority population of T cells may not be sufficient to diminish an autoimmune response. Secondly, the results indicate that induction of anergy of a large proportion of peptide-specific T cells does not lead to a suppressive bystander effect on the remaining responsive T cells. These results emphasize the need to define the dominant autoantigenic epitopes in human autoimmune diseases, since peptide based therapy such as the use of peptide analogues to induce anergy or a change in cytokine profile, is possibly more effective in controlling undesired immune responses than the use of non-antigen, TCR-directed approaches such as superantigens

Comparison of peptide and superantigen-induced anergy in a peptide-specific polyclonal human T cell line.

T cells recognizing tetanus toxin peptide 'p2' (sequence 830-844) raised in HLA DR6 individuals preferentially express V beta 2 in the TCR. A p2-specific T cell line (60% V beta 2+) was used to compare peptide and superantigen [toxic shock syndrome toxin-1 (TSST-1)]-induced clonal anergy. Many experiments consistently revealed that the degree of 'tolerance' or 'clonal anergy' induced by peptide was greater than with the superantigen TSST-1. These results are of interest in a number of contexts. First they suggest that using superantigens or anti-V beta to delete the majority population of T cells may not be sufficient to diminish an autoimmune response. Secondly, the results indicate that induction of anergy of a large proportion of peptide-specific T cells does not lead to a suppressive bystander effect on the remaining responsive T cells. These results emphasize the need to define the dominant autoantigenic epitopes in human autoimmune diseases, since peptide based therapy such as the use of peptide analogues to induce anergy or a change in cytokine profile, is possibly more effective in controlling undesired immune responses than the use of non-antigen, TCR-directed approaches such as superantigens

miR-19-mediated inhibition of transglutaminase-2 leads to enhanced invasion and metastasis in colorectal cancer

Transglutaminase-2 (TG2) is a critical cross-linking enzyme in the extracellular matrix (ECM) and tumor microenvironment (TME). Although its expression has been linked to colorectal cancer, its functional role in the processes that drive disease appears to be context dependent. There is now considerable evidence of a role for microRNAs (miRNA) in the development and progression of cancer, including metastasis. A cell model of metastatic colon adenocarcinoma was used to investigate the contribution of miRNAs to the differential expression of TG2, and functional effects on inflammatory and invasive behavior. The impact of TG2 in colorectal cancer was analyzed in human colorectal tumor specimens and by manipulations in SW480 and SW620 cells. Effects on invasive behavior were measured using Transwell invasion assays, and cytokine production was assessed by ELISA. TG2 was identified as a target for miR-19 by in silico analysis, which was confirmed experimentally. Functional effects were evaluated by overexpression of pre-miR-19a in SW480 cells. Expression of TG2 correlated inversely with invasive behavior, with knockdown in SW480 cells leading to enhanced invasion, and overexpression in SW620 cells the opposite. TG2 expression was observed in colorectal cancer primary tumors but lost in liver metastases. Finally, miR-19 overexpression and subsequent decreased TG2 expression was linked to chromosome-13 amplification events, leading to altered invasive behavior in colorectal cancer cells.IMPLICATIONS: Chromosome-13 amplification in advanced colorectal cancer contributes to invasion and metastasis by upregulating miR-19, which targets TG2.<br/