A Fit-for-Purpose Method for the Detection of Human Antibodies to Surface-Exposed Components of BMS-986263, a Lipid Nanoparticle-Based Drug Product Containing a siRNA Drug Substance

ND-L02-s0201/BMS-986263 is a lipid nanoparticle (LNP) drug product containing a heat shock protein 47 (HSP47)–specific small interfering ribonucleic acid (siRNA) and being developed for the treatment of liver and idiopathic pulmonary fibrosis. To address immunogenicity-related issues, we developed a robust, fit-for-purpose (FFP) three-tier electrochemiluminescent (ECL) anti-drug antibody (ADA) assay for the detection of antibodies (Abs) generated to surface-exposed components of BMS-986263. The drug was coated directly on plates, and several Abs specific for polyethylene glycol (PEG) and other surface components were tested for use as positive quality controls (QCs). Following selection of a rabbit monoclonal anti-PEG Ab, the assay was optimized, and various method development challenges specific to the modality and pseudo surrogate rabbit control were addressed. Screening, confirmatory, and titer cut points were validated following a statistical evaluation of 41 individual K 2 EDTA human plasma samples at a minimum required dilution (MRD) of 100. Assay precision, sensitivity, selectivity, drug tolerance, and hook effect were determined for the rabbit Ab prepared in human K 2 EDTA plasma matrix. The assay was used to interrogate anti-drug Ab (ADA) responses in normal human subjects who were administered 90 mg of the drug intravenously (IV) once every week for 3 weeks in phase I clinical trials. All pre- and post-dose samples were found to be negative for ADA. Based on these results, we concluded that BMS-986263 is not immunogenic. To the best of our knowledge, this work represents the first ADA method developed and reported for an LNP-based drug product.