Chenxiong Le

MedImmune, LLC, GAI, Maryland, United States

Are you Chenxiong Le?

Claim your profile

Publications (4)27.61 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective To assess the pharmacodynamic effects of sifalimumab, an investigational anti-IFN-α monoclonal antibody, in the blood and muscle of adult dermatomyositis and polymyositis patients by measuring neutralisation of a type I IFN gene signature (IFNGS) following drug exposure. Methods A phase 1b randomised, double-blinded, placebo controlled, dose-escalation, multicentre clinical trial was conducted to evaluate sifalimumab in dermatomyositis or polymyositis patients. Blood and muscle biopsies were procured before and after sifalimumab administration. Selected proteins were measured in patient serum with a multiplex assay, in the muscle using immunohistochemistry, and transcripts were profiled with microarray and quantitative reverse transcriptase PCR assays. A 13-gene IFNGS was used to measure the pharmacological effect of sifalimumab. Results The IFNGS was suppressed by a median of 53–66% across three time points (days 28, 56 and 98) in blood (p=0.019) and 47% at day 98 in muscle specimens post-sifalimumab administration. Both IFN-inducible transcripts and proteins were prevalently suppressed following sifalimumab administration. Patients with 15% or greater improvement from baseline manual muscle testing scores showed greater neutralisation of the IFNGS than patients with less than 15% improvement in both blood and muscle. Pathway/functional analysis of transcripts suppressed by sifalimumab showed that leucocyte infiltration, antigen presentation and immunoglobulin categories were most suppressed by sifalimumab and highly correlated with IFNGS neutralisation in muscle. Conclusions Sifalimumab suppressed the IFNGS in blood and muscle tissue in myositis patients, consistent with this molecule's mechanism of action with a positive correlative trend between target neutralisation and clinical improvement. These observations will require confirmation in a larger trial powered to evaluate efficacy.
    Full-text · Article · Feb 2013 · Annals of the rheumatic diseases
  • [Show abstract] [Hide abstract]
    ABSTRACT: Type I interferons (IFNs) appear to play a central role in disease pathogenesis in systemic lupus erythematosus (SLE), making them potential therapeutic targets. Safety profile, pharmacokinetics, immunogenicity, pharmacodynamics and clinical activity of sifalimumab, an anti-IFNα monoclonal antibody, were assessed in a phase I, multicentre, randomised, double-blind, dose-escalation study with an open-label extension in adults with moderately active SLE. received one intravenous dose of sifalimumab (n=33 blinded phase, 0.3, 1, 3, 10 or 30 mg/kg; n=17 open-label, 1, 3, 10 or 30 mg/kg) or placebo (n=17). Each phase lasted 84 days. Adverse events (AEs) were similar between groups; about 97% of AEs were grade 1 or 2. All grade 3 and 4 AEs and all serious AEs (2 placebo, 1 sifalimumab) were deemed unrelated to the study drug. No increase in viral infections or reactivation was observed. Sifalimumab caused dose-dependent inhibition of type I IFN-induced mRNAs (type I IFN signature) in whole blood and corresponding changes in related proteins in affected skin. Exploratory analyses showed consistent trends toward improvement in disease activity in sifalimumab-treated versus placebo-treated subjects. A lower proportion of sifalimumab-treated subjects required new or increased immunosuppressive treatments (12% vs 41%; p=0.03) and had fewer Systemic Lupus Erythematosus Disease Activity Index flares (3% vs 29%; p=0.014). Sifalimumab had a safety profile that supports further clinical development. This trial demonstrated that overexpression of type I IFN signature in SLE is at least partly driven by IFNα, and exploratory analyses suggest that IFNα inhibition may be associated with clinical benefit in SLE. Trial registration number NCT00299819.
    No preview · Article · Jul 2011 · Annals of the rheumatic diseases
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Interleukin-9 (IL-9)-targeted therapies may offer a novel approach for treating asthmatics. Two randomized placebo-controlled studies were conducted to assess the safety profile and potential efficacy of multiple subcutaneous doses of MEDI-528, a humanized anti-IL-9 monoclonal antibody, in asthmatics. Study 1: adults (18-65 years) with mild asthma received MEDI-528 (0.3, 1, 3 mg/kg) or placebo subcutaneously twice weekly for 4 weeks. Study 2: adults (18-50 years) with stable, mild to moderate asthma and exercise-induced bronchoconstriction received 50 mg MEDI-528 or placebo subcutaneously twice weekly for 4 weeks. Adverse events (AEs), pharmacokinetics (PK), immunogenicity, asthma control (including asthma exacerbations), and exercise challenge test were evaluated in study 1, study 2, or both. In study 1 (N = 36), MEDI-528 showed linear serum PK; no anti-MEDI-528 antibodies were detected. Asthma control: 1/27 MEDI-528-treated subjects had 1 asthma exacerbation, and 2/9 placebo-treated subjects had a total of 4 asthma exacerbations (one considered a serious AE). In study 2, MEDI-528 (n = 7) elicited a trend in the reduction in mean maximum decrease in FEV1 post-exercise compared to placebo (n = 2) (-6.49% MEDI-528 vs -12.60% placebo; -1.40% vs -20.10%; -5.04% vs -15.20% at study days 28, 56, and 150, respectively). Study 2 was halted prematurely due to a serious AE in an asymptomatic MEDI-528-treated subject who had an abnormal brain magnetic resonance imaging that was found to be an artifact on further evaluation. In these studies, MEDI-528 showed an acceptable safety profile and findings suggestive of clinical activity that support continued study in subjects with mild to moderate asthma.
    Full-text · Article · Feb 2011 · BMC Pulmonary Medicine
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Interferon-alfa (IFN-alpha) has been implicated in the pathogenesis of psoriasis. To evaluate the safety profile of MEDI-545, a fully human anti-IFN-alpha monoclonal antibody and to explore its effect on the involvement of type I IFN-alpha activity in the maintenance of established plaque psoriasis. We conducted an 18-week, randomized, double-blind, placebo-controlled, dose-escalating study in 36 subjects with chronic plaque psoriasis. Subjects received one intravenous dose of MEDI-545 (0.3-30.0 mg/kg) or placebo. Study outcomes were safety profile, pharmacokinetics, immunogenicity, and clinical effects. There was no difference in adverse events between MEDI-545 and placebo. Two serious adverse events were reported; one drug-related hypotensive infusion reaction occurred in one subject in the 30.0 mg/kg MEDI-545 dose group, causing discontinuation of study drug in that subject and study dismissal of the other subjects in the same cohort; and a myocardial infarction occurred in one subject in the 10 mg/kg MEDI-545 dose group, which was considered to be unrelated to treatment. MEDI-545 was nonimmunogenic, had a half-life of 21 days, showed no significant inhibition of the type I IFN gene signature, and had no clinical activity. The study addressed only IFN-alpha and chronic psoriatic lesions. The safety profile of MEDI-545 supports further clinical development. IFN-alpha does not appear to be significantly involved in the maintenance of established plaque psoriasis.
    Full-text · Article · Mar 2010 · Journal of the American Academy of Dermatology