Improving sensitivity and drug tolerance of assays for neutralizing anti-drug antibodies to semaglutide and native GLP-1

The purpose of this work was to optimize the sensitivity and the drug tolerance of two cell-based assays for the detection of neutralizing antibodies (nAbs) to semaglutide (a GLP-1 analogue) and to endogenous GLP-1. The two assays were developed and validated in three distinct iterations. Enhancements in sensitivity and drug tolerance were achieved through platform optimization, sample pre-treatment and the alteration of control antibodies. The sensitivity and drug tolerance improved gradually with the different versions of the assays. For detection of nAbs to semaglutide, sensitivity was improved from 3,400 ng to 98 ng/ml antibody, and drug tolerance was improved from 2.5 nM semaglutide when detecting 3,400 ng/ml antibodies to 4.8–5.6 nM semaglutide when detecting 1,000 ng/ml antibody. For the endogenous GLP-1 assay, sensitivity was improved from 6,900 ng/ml to 46 ng/ml antibody, and drug tolerance improved from 1.0 nM semaglutide when detecting antibody concentration of 8,800 ng/ml to 2.5 nM semaglutide when detecting 1,000 ng/ml antibody. Key factors for enhancing the sensitivity and drug tolerance of the assays included the concentration of the drug standard for receptor activation, pre-treatment of the samples, and better understanding of the binding properties of the control antibody. This study aimed to improve two cell-based tests that measure the presence of neutralizing antibodies against semaglutide, a medication similar to glucagon-like peptide-1 (GLP-1), and against the body’s own GLP-1. The researchers created and refined these tests in three different stages. They improved how sensitive the tests were and how much of the drug the tests could handle by optimizing the testing process, preparing samples in specific ways, and changing the control antibodies used. The results showed significant improvements. Overall, the study found that making changes to drug amounts, properly preparing samples, and understanding how control antibodies bind to the drugs were key for these improvements.