Comparative technical and operational assessment of current and emerging bench-scale lipid nanoparticle platforms for production of mRNA vaccines

Four laboratory-scale lipid nanoparticle (LNP) mixing platforms were evaluated for producing messenger ribonucleic acid (mRNA)–encapsulated LNPs with product attributes similar to the benchmark SARS-CoV-2 mRNA vaccine. For the comparative technical assessment, parameters such as lipid composition; the molar ratio of cationic polymer amine groups to nucleic acid phosphate groups; aqueous to organic ratio; and mRNA payload were kept identical across all tested mixing platforms. Each platform was evaluated based on operational ease of use, and the mRNA-LNPs produced on each platform were assessed based on multiple parameters, such as physicochemical product attributes and in vivo performance. Multiple batches of LNPs incorporating two different-sized mRNA constructs, luciferase, and SARS-CoV-2 (approximately 2000 and 4000 nucleotides, respectively) were produced on each platform. The LNPs produced on the three micromixing platforms demonstrated similar product attributes in terms of particle size, polydispersity index, mRNA encapsulation efficiency, structural morphology, and immune response. The fourth platform, involving a rotor-stator mixing approach, showed larger particle size, lower encapsulation, and lower immune response compared to the other three tested platforms. Three micromixing approaches were shown to produce mRNA-encapsulated LNPs with highly reproducible and consistent product attributes, structural features, in vivo luciferase protein expression, and generation of immunoglobulin G against SARS-CoV-2. The operational use for each platform varied in terms of equipment setup, use of disposable or reusable workflow accessories, cleaning protocol, cleaning time, and user-controlled interface, all of which are summarized in this work. • Lipid nanoparticle technology for mRNA delivery is rapidly developing. • This work presents a unique comparative study of four benchtop LNP production platforms for delivery of mRNA vaccines. • Platforms were evaluated based on product attributes and operationality. • mRNA encapsulated LNPs produced on different platforms were compared to benchmark SARS-CoV-2 vaccine.