Abstract
BACKGROUND: Cell and Gene Therapy (CGT) utilizes a nucleic acid core, which makes quantitative PCR (qPCR) a critical tool for establishing pharmacokinetics profiles supporting preclinical and clinical studies of CGT programs. Recently, digital PCR (dPCR) has gained traction in the CGT space. AIM: Here we report a comparison of assay performance between qPCR and a nanoplate-based digital platform in a mouse biodistribution study. METHODS: This study adapted a validated duplex qPCR method for quantifying gene therapy genome copy numbers to a nanoplate-based digital PCR method. The assay performance and bioanalysis results with both methods were compared. RESULTS: The qPCR assay exhibited a broader dynamic range (up to 1e8 copies per reaction) while dPCR covered up to 5e6 copies per reaction with dilutional linearity. Both methods showed comparable Limit of Detection and assay sensitivity. The dPCR demonstrated a superior recovery of spiked targets in matrices, including off-target tissues, with only 1/10 of the input matrix. CONCLUSIONS: Both platforms pose strengths and limitations. The dPCR offers a better option for biodistribution studies for its overall superior recovery in tissues tested. With a wider dilutional linearity, the dPCR may serve as a preferable option for preclinical biodistribution studies.