The dupilumab regimen of 300 mg every 2 weeks is approved for uncontrolled, moderate to severe atopic dermatitis (AD). OBJECTIVE To assess the efficacy and safety of different dupilumab regimens in maintaining response after 16 weeks of initial treatment. DESIGN, SETTING, AND PARTICIPANTS The Study to Confirm the Efficacy and Safety of Different Dupilumab Dose Regimens in Adults With Atopic Dermatitis (LIBERTY AD SOLO-CONTINUE) was a randomized, double-blind, phase 3 clinical trial conducted from March 25, 2015, to October 18, 2016, at 185 sites in North America, Europe, Asia, and Japan. Patients with moderate to severe AD who received dupilumab treatment and achieved an Investigator's Global Assessment score of 0 or 1 or 75% improvement in Eczema Area and Severity Index scores (EASI-75) at week 16 in 2 previous dupilumab monotherapy trials (LIBERTY AD SOLO 1 and 2) were rerandomized in SOLO-CONTINUE. After completing SOLO-CONTINUE, patients were followed up for up to 12 weeks or enrolled in an open-label extension. Data were analyzed from December 5 to 12, 2016. INTERVENTIONS High-responding patients treated with dupilumab in SOLO were rerandomized 2:1:1:1 to continue their original regimen of dupilumab, 300 mg, weekly or every 2 weeks or to receive dupilumab, 300 mg, every 4 or 8 weeks or placebo for 36 weeks. MAIN OUTCOMES AND MEASURES Percentage change in EASI score from baseline during the SOLO-CONTINUE trial, percentage of patients with EASI-75 at week 36, and safety. RESULTS Among the 422 patients (mean [SD] age, 38.2 [14.5] years; 227 [53.8%] male), continuing dupilumab treatment once weekly or every 2 weeks maintained optimal efficacy, with negligible change in percent EASI improvement from SOLO 1 and 2 baseline during the SOLO-CONTINUE trial (−0.06%; P < .001 vs placebo); percent change with the other regimens dose-dependently worsened (dupilumab every 4 weeks, −3.84%; dupilumab every 8 weeks, −6.84%; placebo, −21.67%). More patients taking dupilumab weekly or every 2 weeks (116 of 162 [71.6%]; P < .001 vs placebo) maintained EASI-75 response than those taking dupilumab every 4 weeks (49 of 84 [58.3%]) or every 8 weeks (45 of 82 [54.9%]) or those taking placebo (24 of 79 [30.4%]). Overall adverse event incidences were 70.7% in the weekly or every 2 weeks group, 73.6% in the every 4 weeks group, 75.0% in the every 8 weeks group, and 81.7% in the placebo group. Treatment groups had similar conjunctivitis rates. Treatment-emergent antidrug antibody incidence was lower with more frequent dupilumab dose regimens (11.3% in the placebo group and 11.7%, 6.0%, 4.3%, and 1.2% in the dupilumab every 8 weeks, every 4 weeks, every 2 weeks, and weekly groups, respectively). CONCLUSIONS AND RELEVANCE In this trial, continued response over time was most consistently maintained with dupilumab administered weekly or every 2 weeks. Longer dosage intervals and placebo resulted in a diminution of response for both continuous and categorical end points. No new safety signals were observed. The approved regimen of 300 mg of d...

is a principal investigator and advisory board member for AbbVie; is an advisory board member for Eli Lilly; is a principal investigator for LEO Pharma; is a principal investigator and advisory board member for Pfizer; is a principal investigator, provides research support, has received honoraria for lecturing, and is an advisory board member and consultant for Regeneron Pharmaceuticals and Sanofi Genzyme; and is an advisory board member for UCB. Dr Blauvelt is a scientific advisor and clinical study investigator for

3Celiac disease (CD) is an autoimmune disorder induced by gluten intake in genetically susceptible individuals. It is characterized by the presence of serum antibodies to endomysium, reticulin, gliadin, and tissue transglutaminase. The incidence of CD in various autoimmune disorders is increased 10-to 30-fold in comparison to the general population, although in many cases CD is clinically asymptomatic or silent. The identification of such cases with CD is important since it may help in the control of type I diabetes or endocrine functions in general, as well as in the prevention of long-term complications of CD, such as lymphoma. It is believed that CD may predispose an individual to other autoimmune disorders such as type I diabetes, autoimmune thyroid, and other endocrine diseases and that gluten may be a possible trigger. The onset of type I diabetes at an early age in patients with CD, compared to non-CD, and the prevention or delay in onset of diabetes by gluten-free diet in genetically predisposed individuals substantiates this antigen trigger hypothesis. Early identification of CD patients in highly susceptible population may result in the treatment of subclinical CD and improved control of associated disorders.Autoimmunity as a concept evolved from the beginning of this century, when Ehrlich and Morgenroth (26) introduced the phenomenon of "horror autotoxicus," i.e., fear of selfpoisoning. Subsequently, many diseases were recognized with etiology arising from the abnormal reaction of the immune system to self antigens. These observations laid the foundation for establishing postulates that are characteristic of an autoimmune disease (4, 7). Since then, several hypotheses have been put forward regarding the mechanisms of autoimmunity (22,76,84,110,118).In general, autoimmune disorders can be classified as either organ specific or non-organ specific. In organ-specific autoimmune diseases, the autoantibodies are specifically directed against antigens localized in a particular organ and are often detected in circulation. Examples of organ-specific autoimmunity include Hashimoto's thyroiditis, type I diabetes, and myasthenia gravis.In contrast, the non-organ-specific autoimmune disorders are characterized by the presence of autoantibodies directed against ubiquitous antigens (not specific to a particular organ). This results in the involvement of several organs and is often characterized by the presence of specific circulating immune complexes. Non-organ-specific autoimmunity includes diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and scleroderma.Epidemiologic studies have shown that genetic factors are involved in host susceptibility to autoimmune disease. For example, the concordance rate of a particular autoimmune diseases is much higher in monozygotic twins in comparison to fraternal twins (17). Moreover, this incidence is much higher in organ-specific autoimmune disorders in comparison to nonorgan-specific disorders. Thus, in Grave's thyrotoxicosis, Hashimoto's disease, a...

The 2019 13th Workshop on Recent Issues in Bioanalysis (WRIB) took place in New Orleans, LA, USA on April 1–5, 2019 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day, week-long event – a full immersion week of bioanalysis, biomarkers, immunogenicity and gene therapy. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule bioanalysis involving LCMS, hybrid LBA/LCMS, LBA cell-based/flow cytometry assays and qPCR approaches. This 2019 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2019 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers New Insights in Biomarker Assay Validation, Current & Effective Strategies for Critical Reagent Management, Flow Cytometry Validation in Drug Discovery & Development & CLSI H62, Interpretation of the 2019 FDA Immunogenicity Guidance and Gene Therapy Bioanalytical Challenges. Part 1 (Innovation in Small Molecules and Oligonucleotides & Mass Spectrometry Method Development Strategies for Large Molecule Bioanalysis) and Part 2 (Recommendations on the 2018 FDA BMV Guidance, 2019 ICH M10 BMV Draft Guideline and regulatory agencies' input on bioanalysis, biomarkers, immunogenicity and gene therapy) are published in volume 11 of Bioanalysis, issues 22 and 23 (2019), respectively.

The immunogenicity profile of a biotherapeutic is determined by a multitude of product and patient-related risk factors that can influence the observed incidence and clinical consequences of immunogenicity. Pre-existing antibodies, i.e., biotherapeutic-reactive antibodies present in samples from treatment-naïve subjects, have been commonly observed during immunogenicity assessments; however their relevance in terms of the safety and efficacy of a biotherapeutic is poorly understood. An American Association of Pharmaceutical Scientists-sponsored survey was conducted to gather information about the prevalence, nature, and consequences of pre-existing antibodies in clinical and nonclinical studies. The survey results indicate that pre-existing antibodies against a variety of biotherapeutics (e.g., mAbs, fusion proteins) are frequently encountered, especially in the context of autoimmune diseases, but that the methods and approaches used to detect, characterize, and report these antibodies vary. In most cases, pre-existing antibodies did not appear to have clinical consequences; however, a few of the respondents reported having observed an effect on pharmacokinetic, pharmacodynamic, safety, and/or efficacy parameters. The findings from this survey are an important first step in evaluating the potential risks associated with the presence of pre-existing antibodies and highlight the importance of standardizing the approaches for detection and characterization of these antibodies. Cross-industry sharing of case studies and relevant data collection will help better inform biotherapeutic risk/benefit profiles and provide deeper understanding of the biological consequences of pre-existing antibodies.