Liquid chromatography-mass spectrometry method for the quantification of an anti-sclerostin monoclonal antibody in cynomolgus monkey serum / 药物分析学报

Liquid chromatography tandem mass spectrometry (LC-MS/MS) has gradually become a promising alternative to ligand binding assay for the bioanalysis of biotherapeutic molecules,due to its rapid method development and high accuracy.In this study,we established a new LC-MS/MS method for the determination of the anti-sclerostin monoclonal antibody (SHR-1222) in cynomolgus monkey serum,and compared it to a previous electrochemiluminescence method.The antibody was quantified by detecting the surrogate peptide obtained by trypsin digestion.The surrogate peptide was carefully selected by investigating its uniqueness,stability and MS response.The quantitative range of the pro-posed method was 2.00-500 μg/mL,and this verified method was successfully applied to the tox-icokinetic assessment of SHR-1222 in cynomolgus monkey serum.It was found that the concentrations of SHR-1222 in cynomolgus monkeys displayed an excellent agreement between the LC-MS/MS and electrochemiluminescence methods (ratios of drug exposure,0.8-1.0).Notably,two monkeys in the 60 mg/kg dose group had abnormal profiles with a low detection value of SHR-1222 in their individual sample.Combining the high-level anti-drug antibodies (ADAs) in these samples and the consistent quantitative results of the two methods,we found that the decreased concentration of SHR-1222 was due to the accelerated clearance mediated by ADAs rather than the interference of ADAs to the detection platform.Taken together,we successfully developed an accurate,efficient and cost-effective LC-MS/MS method for the quantification of SHR-1222 in serum samples,which could serve as a powerful tool to improve the preclinical development of antibody drugs.

Pharmacokinetics of monoclonal antibodies and Fc-fusion proteins

There are many factors that can influence the pharmacokinetics (PK) of a mAb or Fc-fusion molecule with the primary determinant being FcRn-mediated recycling. Through Fab or Fc engineering, IgG-FcRn interaction can be used to generate a variety of therapeutic antibodies with significantly enhanced half-life or ability to remove unwanted antigen from circulation. Glycosylation of a mAb or Fc-fusion protein can have a significant impact on the PK of these molecules. mAb charge can be important and variants with pI values of 1-2 unit difference are likely to impact PK with lower pI values being favorable for a longer half-life. Most mAbs display target mediated drug disposition (TMDD), which can have significant consequences on the study designs of preclinical and clinical studies. The PK of mAb can also be influenced by anti-drug antibody (ADA) response and off-target binding, which require careful consideration during the discovery stage. mAbs are primarily absorbed through the lymphatics via convection and can be conveniently administered by the subcutaneous (sc) route in large doses/volumes with co-formulation of hyaluronidase. The human PK of a mAb can be reasonably estimated using cynomolgus monkey data and allometric scaling methods.

Higher body mass index and anti-drug antibodies predict the discontinuation of anti-TNF agents in Korean patients with axial spondyloarthritis / O maior índice de massa corporal e a presença de anticorpos antifármacos predizem a interrupção no uso de agentes anti-TNF em pacientes sul-coreanos com espondiloartrite axial

ABSTRACT Objective: The development of anti-drug antibodies against tumor necrosis factor inhibitors is a likely explanation for the failure of TNF-inhibitors in patients with spondyloarthritis. Our study determined the existence and clinical implications of ADAbs in axial spondyloarthritis patients. Methods: According to the Assessment of SpondyloArthritis International Society classification criteria for axial spondyloarthritis, patients treated with adalimumab or infliximab were recruited consecutively. Serum samples were collected at enrollment to measure anti-drug antibodies and drug levels. Results: Of 100 patients, the mean duration of current TNF inhibitor use was 22.3 ± 17.9 months. Anti-drug antibodies were detected in 5 of 72 adalimumab users compared to 5 of 28 infliximab users (6.9% vs. 17.9%). Anti-drug antibodies-positive patients had a significantly higher body mass index than anti-drug antibodies-negative patients among both adalimumab (28.4 ± 5.9 kg/m2 vs. 24.3 ± 2.9 kg/m2, respectively, p = 0.01) and infliximab users (25.9 ± 2.8 kg/m2 vs. 22.6 ± 2.8 kg/m2, respectively, p = 0.02). During the median 15-month follow-up period, drug discontinuation occurred more frequently in the anti-drug antibodies-positive group than the anti-drug antibodies-negative group (30.0% vs. 6.5%, respectively, p = 0.04). In logistic regression, anti-drug antibodies positivity (OR = 5.85, 95% CI 1.19-28.61, p = 0.029) and body mass index (OR = 4.35, 95% CI 1.01-18.69, p = 0.048) were associated with a greater risk of stopping TNF inhibitor treatment. Conclusions: Our result suggests that the presence of anti-drug antibodies against adalimumab and infliximab as well as a higher body mass index can predict subsequent drug discontinuation in axial spondyloarthritis patients.

RESUMO Objetivo: O desenvolvimento de anticorpos antifármacos (ADAb) contra o fator de necrose tumoral (TNF) é uma explicação provável para a falha dos anti-TNF em pacientes com espondiloartrites (EspA). O presente estudo determinou a presença e as implicações clínicas dos ADAb em pacientes com EspA axiais. Métodos: De acordo com os critérios de classificação para EspA axial da Assessment of SpondyloArthritis International Society, recrutaram-se consecutivamente pacientes tratados com adalimumabe ou infliximabe. Coletaram-se amostras de soro no momento da entrada no estudo para medir os níveis de ADAb e de fármaco. Resultados: Dos 100 pacientes, a duração média de uso dos anti-TNF atuais foi de 22,3 ± 17,9 meses. Os ADAb foram detectados em cinco de 72 pacientes em uso de adalimumabe, em comparação com cinco de 28 usuários de infliximabe (6,9% vs. 17,9%). Os pacientes ADAb-positivos tinham um índice de massa corporal maior do que aqueles ADAb-negativos, tanto entre indivíduos em uso de adalimumabe (28,4 ± 5,9 kg/m2 vs. 24,3 ± 2,9 kg/m2, respectivamente, p = 0,01) quanto de infliximabe (25,9 ± 2,8 kg/m2 vs. 22,6 ± 2,8 kg/m2 respectivamente, p = 0,02). Durante o período médio de seguimento de 15 meses, a suspensão do fármaco ocorreu com maior frequência no grupo ADAb-positivo do que no grupo ADAb-negativo (30,0% vs. 6,5%, respectivamente, p = 0,04). Na regressão logística, a positividade no ADAb (OR = 5,85, IC 95% 1,19 a 28,61, p = 0,029) e o IMC (OR = 4,35, IC 95% 1,01 a 18,69, p = 0,048) esteve associada a um maior risco de interromper o tratamento com anti-TNF. Conclusões: Os resultados do presente estudo sugerem que a presença de ADAb contra o adalimumabe e o infliximabe, bem como um IMC mais alto, pode predizer a subsequente interrupção do fármaco em pacientes com EspA axial.

An acid dissociation bridging ELISA assay for detection of antibodies against therapeutic monoclonal antibody Arzerra™ in cynomolgus serum / 中国药学杂志

OBJECTIVE: To develop and validate an acid dissociated bridging ELISA assay for determination of antibodies (ADAs) against a human monoclonal antibody against CD20, Arzerra™, in cynomulgus serum, which will be used to reflect the immunogenicity of Arzerra™ in cynomolgus serum. METHODS: Biotin labeled Arzerra™ and acid treated unknown samples were added into the Arzerra™ pre-coated 96-well plates, sequentially. Positive controls (ADAs) in unknown samples bridged with coated Arzerra™ and biotin-labeled Arzerra™(Biotin-Drug) to generate ADAs bridged compounds (Drug-ADAs-Biotin-Drug), and coloration was made with enzymatic reaction. RESULTS: The sensitivity was 7.4 ng·mL-1, and the intra-assay and the inter-assay RSDs were less than 17. 6% for positive controls. The screening cut point (SCP) for this assay was 1.23 and the confirmatory cut point (CCP) was 42. 8%. The assay also showed high drug tolerance, which was 20 fold at 2.0 μg·mL-1 ADA level (Drug: ADA = 40.0 μg·mL-1: 2.0 μg·mL-1) ; and no"Hook effect"was detected within 3.2-100 000.0 ng·mL-1. Using this assay to determine ADAs against Arzerra™ in Cynomolgus serum, ADAs were detected at 21 d post administration. CONCLUSION: The bridging ELISA is one of the best assays to determine ADAs against therapeutic monoclonal antibodies, because it shows high sensitivity and good drug tolerance.

Technical considerations on the study and evaluation of the biosimilars' immunogenicity / 中国药学杂志

OBJECTIVE: To evaluate the immunogenicity of biosimilars. METHODS: Non-clinical and clinical studies carried out in accordance with the guidelines in immunological characteristics and immunogenicity of biosimilars should focus on the production of anti-drug antibodies and detection of drug-resistant properties, immune complexes and their potential effects on pharmacodynamics/pharmacokinetics. Assays for immunogenicity of biological agents mainly include enzyme linked immunosorbent assay (ELISA), radioimmunoassay, surface plasm on resonance method, enzyme linked immunospot assay, immuno-PCR method, cell proliferation assay, etc. RESULTS AND CONCLUSION: Biosimilars immunogenicity should be comprehensively interpreted based on both the preclinical/clinical evaluation results and the prevalence of clinical adverse events.