RNA-based therapeutics, which function by either silencing pathological genes through delivery of siRNA or expressing therapeutic proteins through the delivery of exogenous mRNA to cells, hold great potential for the treatment of various diseases, like Covid-19 related diseases. However, mRNA molecules are large, fragile and easily degrade. They do not readily cross plasma membranes to enter target cells and so a delivery solution is required.

Lipid nanoparticles (LNP) are the leading delivery systems for enabling the therapeutic potential of small interfering RNA (siRNA), mRNA for systemic applications or CRISPR. Lipid nanoparticles (LNPs), currently represent the most advanced platform for RNA delivery, which have now advanced into human clinical trials and their mRNA delivery safety profiles have been evaluated in human and non-human primates.

Lipid nanoparticle delivery platforms have been extensively investigated and optimized for the formulation of oligonucleotide drug products and provide a good basis for mRNA based systems. However, mRNA containing LNPs need to be treated differently than oligonucleotide containing LNPs, as particle structure has an impact with respect to stability upon processing conditions. Data will be presented, which describe hurdles and solutions throughout these processes.