Overcoming target interference in bridging anti-drug antibody (ADA) assay by optimizing sample treatment

Drug bridging immunoassays are widely employed as the standard approach for detecting anti-drug antibodies (ADAs) in the development of new biological entities. A major challenge in these assays is mitigating target interference, particularly when the soluble target exists in dimeric forms, which can result in false positive signals and compromise assay specificity. We developed sensitive and robust ADA assays capable of overcoming target interference to detect antibodies against BI X in both cynomolgus monkey (cyno) plasma and human serum matrices. This was achieved through the implementation of simple sample treatment techniques, specifically, acidification using a panel of different acids, to disrupt dimeric target interactions and minimize the interference. Optimization of the acid dissociation and subsequent neutralization steps significantly reduced target interference in both cyno and human matrices. These improvements were achieved without the need for additional assay development or complex depletion strategies. Compared to previously reported methods for mitigating target interference, the acid panel treatment approach is simpler, more time-efficient, and cost-effective. This user-friendly strategy can be readily applied to eliminate soluble dimeric targets during ADA method development, particularly in cases where alternative methodologies are not feasible or applicable.

药物桥接免疫分析法（Drug bridging immunoassays）作为新型生物制剂研发过程中检测抗药物抗体（anti-drug antibodies, ADAs）的标准方法被广泛应用。此类分析方法的核心挑战之一是缓解靶标干扰，尤其当可溶性靶标以二聚体形式存在时，这会引发假阳性信号并削弱分析方法的特异性。本研究开发了灵敏且稳健的ADA分析方法，可克服靶标干扰，在食蟹猴（cynomolgus monkey, cyno）血浆与人血清基质中检测针对BI X的抗体。该方法通过简单的样本处理技术实现，具体为采用多种酸进行酸化处理，以破坏二聚体靶标的相互作用并最大限度降低干扰。对酸解离及后续中和步骤的优化，显著降低了食蟹猴与人血清基质中的靶标干扰。上述优化无需额外开展分析方法开发或采用复杂的耗竭策略即可达成。与此前报道的缓解靶标干扰的方法相比，多酸处理策略更为简便、省时且经济高效。这种操作友好的策略可在ADA分析方法开发过程中便捷应用，用于消除可溶性二聚体靶标，尤其适用于其他方法不可行或不适用的场景。