Abstract
LNPs are by far the predominant delivery vectors for therapeutic mRNA. Their quality, safety and efficacy are crucially dependent on the choice of lipids, and also the formulation parameters.
mRNA-LNPs are unusually complex drugs, both in terms of their non-covalent internal structure which affects loading and stability, mRNA as a fragile and very large API, but also with regards to the effective surface chemistry and its in vivo interactions. This places unique demands on analytical methods for their characterization and quality control.
In the current work, the selection, suitability and application of analytical methods – and their orthogonality and complementarity, as requested by regulatory authorities – is presented, based on comprehensive comparisons and interlaboratory studies we have performed. A tiered analytical approach is proposed, from the early screening by batch methods like dynamic light scattering (DLS) or nanoparticle tracking analysis (NTA) to more in-depth analyses with e.g. multi-detector field flow fractionation (MF-FFF), differential scanning calorimetry (DSC) and analytical ultracentrifugation (AUC). We show that the latter methods are crucial to discover more subtle differences in LNP quality that are important for biological activity.
mRNA-LNPs are unusually complex drugs, both in terms of their non-covalent internal structure which affects loading and stability, mRNA as a fragile and very large API, but also with regards to the effective surface chemistry and its in vivo interactions. This places unique demands on analytical methods for their characterization and quality control.
In the current work, the selection, suitability and application of analytical methods – and their orthogonality and complementarity, as requested by regulatory authorities – is presented, based on comprehensive comparisons and interlaboratory studies we have performed. A tiered analytical approach is proposed, from the early screening by batch methods like dynamic light scattering (DLS) or nanoparticle tracking analysis (NTA) to more in-depth analyses with e.g. multi-detector field flow fractionation (MF-FFF), differential scanning calorimetry (DSC) and analytical ultracentrifugation (AUC). We show that the latter methods are crucial to discover more subtle differences in LNP quality that are important for biological activity.