Dry powder composition comprising long-chain RNA
The present invention is directed to a storage-stable formulation of long-chain RNA. In particular, the invention concerns a dry powder composition comprising a long-chain RNA molecule. The present invention is furthermore directed to methods for preparing a dry powder composition comprising a long-chain RNA molecule by spray-drying. The invention further concerns the use of such a dry powder composition comprising a long-chain RNA molecule in the preparation of pharmaceutical compositions and vaccines, to a method of treating or preventing a disorder or a disease, to first and second medical uses of such a dry powder composition comprising a long-chain RNA molecule and to kits, particularly to kits of parts, comprising such a dry powder composition comprising a long-chain RNA molecule.
1. A method for preparing a dry powder comprising a long-chain RNA molecule, wherein the method comprises the steps of:
a) providing a liquid comprising the long-chain RNA molecule,
b) spray-drying the liquid of step a) with a spray-drying device having a drying gas inlet and a drying gas outlet, wherein the drying gas has a temperature at the inlet of at least 85° C., wherein the drying gas has a temperature at the outlet of at least 50° C.,
wherein the dry powder has a residual moisture content of 7% (w/w) or less, wherein the long-chain RNA molecule is in a complex with a cationic or polycationic compound, and wherein the long-chain RNA molecule comprises at least 200 nucleotides.
2. The method according to claim 1 , wherein the liquid of step a) further comprises at least one excipient selected from a cryoprotectant, a lyoprotectant and a bulking agent.
3. The method according to claim 1 , wherein the liquid of step a) does not contain a lipid compound.
4. The method according to claim 1 , wherein the liquid of step a) comprises a spray-drying-compatible solvent.
5. The method according to claim 1 , wherein the liquid of step a) is atomized and a droplet resulting from the atomization of the liquid is characterized by a mass median aerodynamic diameter of 300 nm to 200 μm.
6. The method according to claim 1 , which comprises a plurality of particles.
7. The method according to claim 6 , wherein the median particle size in a volume weighted distribution of the resulting dried powder is at least 1 μm.
8. The method according to claim 6 , wherein the average sphericity of the particles in the resulting dried powder is in a range from 0.7 to 1.0.
9. The method according to claim 1 , wherein the long-chain RNA molecule is present in the form of a free long-chain RNA molecule, or in the form of a complex comprising the long-chain RNA molecule.
10. The method according to claim 1 , wherein the long-chain RNA molecule comprises more than 200 nucleotides.
11. The method according to claim 1 , wherein the long-chain RNA molecule comprises at least one modification.
12. The method according to claim 1 , wherein the liquid of step a) further comprises a suspending agent and/or an osmolality of about 200 mosmol/l to about 400 mosmol/l.
13. The method according to claim 5 , wherein at least a first pressure nozzle is used as an atomizer, optionally wherein the pressure is less than about 1 bar.
14. The method according to claim 1 , wherein (a) the method is performed on bulk material, or the method is performed continuously, and/or (b) the method is performed in an open cycle device, or the method is performed in closed cycle device.
15. The method of claim 1 , wherein the dry powder comprises an average particle size of 1 μm to 20 μm.