NucleoDry – exploring the opportunities with dry vaccines

NucleoDry is a unique consortium with expertise ranging from gene therapy development and researh (VIVAC group, Karolinska Institutet, KI) via hospital practice and GMP adaption (Vecura) and formulation development and optimization (RISE) to GMP manufacturing and upscaling (NorthXBio). Together these partners are working on improved collaboration for the benefit of future gene therapy development and manufacturing in Sweden as well as the exploration of dry vaccines with improved storage properties.

Majority of mRNA vaccines developed during the pandemic are formulated in lipid nanoparticles (LNPs) to enhance stability as well as cellular uptake and transfection. This is a complex formulation with demanding storage conditions of -80 to -20 °C putting high demands on distribution chains and storage facilities. Despite demanding storage condition, the shelf-life of the products are relatively short, approximately 6 months. The stability and storage of these products is therefore a major challenge for their availability world-wide. One route to increasing the shelf-life of biological modalities is removing water and obtaining a dry formulation where water is not present to facilitate chemical reactions and alterations. The decreased reactivity of the dry formulation can result in both prolonged shelf-life and increase the possible storage temperature.

There are several techniques for drying formulations. NucleoDry is exploring one option for more stable gene therapies with milder storage demands, lyophilization. Removing water through freeze drying is a gentle method that has been successful for many biological modalities. In the case of vaccines formulated in LNPs it poses several interesting research and development questions:

• Water is an integrated part of LNPs, what happens to the micro and nanostructure of the formulation upon drying?
• What happens to the integrity of the LNPs?
• Can we control how the LNPs are affected by tuning the drying process, or using cryoprotectants or other additives?
• How are the LNPs behaving in a rehydration process?
• Can it be affected by the method of rehydration?
• How is the activity in vitro affected by drying and rehydration?
• How does lyophilization affect product stability for mRNA vaccines?
• How does lyophilization affect storage climate?
• How is the activity in vivo affected by drying and rehydration?

Within NucleoDry mRNA is delivered from the VIVAC group at KI to the formulation unit at RISE. There the nucleotides are formulated in lipid nanoparticles using a microfluidic chip. The formulations are subsequently freeze dried and both wet, dried and resuspended formulations are analyzed for size, z-potential, encapsulation efficiency, cryo-TEM, LRSI x-rays, transfection in cells and mice in collaboration between RISE and KI. Vecura and NorthXBio performs initial evaluations of GMP adaptability of small-scale manufacturing and a plan for upscaling and GMP manufacturing for later clinical stages. These results can be used by other initiatives with the goal of gene therapy development and commercialization, within Sweden and abroad.

NucleoDry’s web page is a part of ri.se, to find out more about RISE, click on the black menu above.