Making RNA for Vaccines More Consistent

CureVac's 2023 patent on a method to create multiple RNA strands with similar numbers of A and U nucleotides, making them easier to purify and use in vaccines.

What it covers

This patent describes a way to prepare RNA strands for things like vaccines. First, you get the instructions (coding sequences) for at least two different RNA molecules, each between 800 and 20,000 units long. The key step is altering the original RNA sequences so that the new versions have a similar count of 'A' and 'U' building blocks, differing by no more than 50 from each other. Then, these 'harmonized' RNA molecules are made. Finally, a mixture of these harmonized RNA molecules is analyzed or purified using a chromatography technique, like High-Performance Liquid Chromatography (HPLC). For example, this could be used to make multiple mRNA strands that each code for a different part of a virus, like influenza antigens, ensuring they are consistent for purification.

What it doesn't cover

• —Methods that do not involve adapting the number of A and/or U nucleotides in the RNA sequence.
• —Methods where the RNA species are not between 800 and 20,000 nucleotides long.
• —Methods where the harmonized RNA species have more than 50 difference in their A and U nucleotide counts.
• —Purification or analysis methods that do not use chromatography.
• —RNA sequences that are not intended for use in vaccines or therapeutic treatments.

The clever bit

The innovation lies in 'harmonizing' the A and U nucleotide counts across different RNA species. This seemingly small change in nucleotide composition significantly impacts how the RNA molecules behave during purification, making the process more efficient and reliable.

Why it matters

This patent is relevant to the production of mRNA vaccines and therapies. Ensuring consistency in the RNA molecules, particularly in their nucleotide composition, is crucial for efficient manufacturing and predictable performance of these advanced medical products.

Real-world examples

• 1.mRNA vaccine production
• 2.Therapeutic RNA manufacturing
• 3.Purification of multiple mRNA constructs