Bioanalysis最新文献

Immunogenicity regulatory guidance and industry recommendations have evolved over the last two decades since unexpected immune reactions were first reported with erythropoietin. Since then, the guidelines and practices for immunogenicity have stemmed from a reaction to a high-risk molecule causing significant clinical impact. Similar thinking is often applied to all biotherapeutic drugs, even when a well-defined risk assessment suggests otherwise. In recent years, the current testing paradigm for immunogenicity has been challenged with more informative approaches being proposed. In a Focus Workshop held by the European Bioanalysis Forum in September 2023, the current immunogenicity testing paradigm was challenged based on the experience and learning of 20+ years of immunogenicity strategies. The workshop recommendations proposed a new paradigm, challenging the value of multiple tiers depending on the immunogenicity risk assessment based on context of use and moving toward treating immunogenicity as a pharmacodynamic biomarker for the drug. Such rethinking ultimately results in the appropriate and efficient focusing of resources on immunogenicity testing strategies that benefit patients most, moving to a new paradigm where implementation of appropriate and truly informative immunogenicity testing strategies, depending on the context-of-use, become the norm .

Aim: We aimed to establish a sensitive LC-MS/MS method to analyze the pharmacokinetics of Ani HBr tablets and injection. Methods: Around 10 mmNH₄Ac containing 0.1% formic acid and acetonitrile were used as the mobile phase. Acute lung injury in septic and normal rats, respectively, were administered Ani HBr tablets at doses of 12.5, 25 and 50 mg/kg and injection at doses of 4, 8 and 16 mg/kg, followed by extraction of the drugs from plasma using ethyl acetate for subsequent analysis. Results & conclusion: The method met the requirements for biological analysis. Ani HBr tablets absorbed slowly in rats with disease, tail vein administration was a more promising approach for treating septic acute lung injury.

Aim: A simple and rapid HPLC technique was developed and validated to simultaneously estimate enzalutamide (ENZ) and repaglinide (REP) in rat plasma. Methods: In silico predictions using DDinter and DDI-Pred indicated possible drug-drug interactions between ENZ and REP. A central composite design was used to identify factors influencing the separation of the drugs. Interactions between chromatographic parameters were studied through 51 experiments, followed by illustration with three-dimensional response surface plots. The four factors optimized for the separation of the two drugs are column temperature (A), % organic strength (B), pH (C) and column type (D). Results: Plate count(R1), tailing factor (R2) and resolution (R3) responses in the experimental design were analyzed with the favorable chromatographic conditions predicted to be 0.1% formic acid and acetonitrile as mobile phases on a Phenomenex C18 LC column (250 × 4.6 mm, 5 μm). The method was applied to estimate the drugs in rat plasma using a simple protein-precipitation step and found to be linear, accurate and precise within the ranges of 0.5-16 and 5-50 μg/ml for ENZ and REP, respectively. Conclusion: The optimized method can be used in future bioanalytical workflow for drug quantification and drug-drug compatible studies.

Aim: The aim was to evaluate drug-plasma binding (DPB).by employing Hollow Fiber-in-Syringe Equilibrium Sampling Through Supported Liquid Membrane (HFiS ESTSLM) and RP-HPLC analysis. Materials & methods: HFiS ESTSLM and RP-HPLC were used to evaluate DPB of three weak basic drugs (Metoprolol, Diphenhydramine, and Sildenafil) with differing hydrophilicity and binding ability to blood plasma. Results: The results exhibited an increasing drug-dependent magnitude of DPB for the three model drugs. This trend of DPB confirmed that HFiS ESTSLM has the required sensitivity for determining DPB of the drugs. The DPB was drug concentration-dependent within the tested drug concentration range, especially at high concentration. Conclusion: HFiS ESTSLM and RP-HPLC offered a simple, easy and cost-effective procedure to evaluate DPB of these basic drugs.

The European Bioanalysis Forum, alongside key industry stakeholders, has been driving the discussions around the implementation of context-of use for biomarker assays to ensure that these assays are validated appropriately depending on their purpose. Insights into understanding why the implementation of context-of-use in assay strategies has also shown that the key stakeholder, or requester for the biomarker data, is responsible for providing the context-of-use statement for all biomarker assay requests. Experts from across the industry haves repeatedly sought a cross-industry recommended format in which the context-of-use statement could be provided. In this manuscript, the European Bioanalysis Forum suggests a format for this.

The European Bioanalysis Forum, in collaboration with several key industry stakeholders, has recently led discussions that address international immunogenicity guidance documents, specifically the three tier approach for immunogenicity testing strategies, after more than 20 years of experience with biotherapeutics. As part of this, the strategy and methods used to assess drug tolerance across all immunogenicity assays are challenged, emphasizing that bioanalytical scientists need to consider the context-of-use of each assay. Here, recommendations for drug tolerance assessments, driven by strong scientific rationale and subject to reevaluation as needed, are provided. This includes carefully considering the drug and positive control concentrations considered to be appropriate and which tiers are most relevant for performing drug tolerance assessments.

Aim: Pharmacokinetic studies in children are limited, in part due to challenges in blood sampling. We compare the use of capillary microsampling and conventional sampling techniques in pediatric patients to show results that can be used in the pharmacokinetic analysis of Cefazolin. Patients & Methods: Paired blood samples (n = 48) were collected from 12 patients (median age/weight 49 months/18 kg). Results: The United States Federal Drug Administration incurred sample reanalysis acceptance criteria was used and identified 79% of paired samples achieved a difference of less than 20% in magnitude with a capillary microsampling bias of -10% (SD 20%). With exclusion of PK outliers, this rose to 88%. Conclusion: Capillary microsampling is reliable, meets acceptance criteria and can be used in pharmacokinetic studies.ACTRN: 12618001469202.

Aim: Bioanalytical assays to measure rhamnose, erythritol, lactulose and sucralose in human urine and plasma were developed to support an indomethacin challenge study for intestinal permeability assessment in healthy participants. Methods: The multi-sugar assays utilized 5-μl sample matrix and a simple chemical derivatization with acetic anhydride, followed by RPLC-MS/MS detection. Results: Rhamnose and erythritol quantification was established between 1.00-1,000 μg/ml in urine and 250-250,000 ng/ml in plasma. For lactulose and sucralose, dynamic ranges of 0.1-100 μg/ml (urine) and 25-25,000 ng/ml (plasma) were applied for biological measurements. Conclusion: This work helped overcome some of the common analytical challenges associated with the bioanalysis of mono- and disaccharides and achieved improved limits of quantification.