Formulation for administration of RNA

1. An injectable pharmaceutical composition comprising:

(a) single stranded, self-replicating RNA encoding a peptide or protein comprising an antigen or epitope, wherein the single stranded, self-replicating RNA is derived from Venezuelan equine encephalitis virus (VEEV) or from Semliki Forest virus (SFV); and

(b) polyethyleneimine

wherein the injectable pharmaceutical is adapted for intramuscular administration, and wherein the single stranded, self-replicating RNA is in an amount effective to elicit an immune response.

2. The composition according to claim 1 , wherein the injectable pharmaceutical composition is adapted for administration to muscle cells or muscle tissue.

3. The composition according to claim 1 , wherein the molar ratio of the number of nitrogen atoms (N) in the polyethyleneimine to the number of phosphor atoms (P) in the single stranded RNA (N:P ratio) is 2.0 to 15.0.

4. The composition according to claim 1 , wherein the ionic strength is 50 mM or less.

5. The composition according to claim 1 , wherein the single stranded, self-replicating RNA is a cis-replicon.

6. The composition according to claim 1 , wherein:

when the single stranded, self-replicating RNA is derived from VEEV, the single stranded, self-replicating RNA corresponds or corresponds essentially to the genomic RNA of VEEV or an attenuated form thereof, wherein the open reading frame encoding structural proteins is replaced by an open reading frame encoding the peptide or protein comprising an antigen or epitope,

wherein the antigen or the peptide or protein comprising an antigen or epitope is a membrane protein comprising a Type I transmembrane protein, a Type II transmembrane protein, a Multipass transmembrane protein, a Lipid chain anchored membrane protein, a GPI-anchored membrane protein, a Peripheral membrane protein, or a viral envelope protein, and/or

wherein the antigen is Influenza hemagglutinin; or

when the single stranded, self-replicating RNA is derived from SFV, the single stranded, self-replicating RNA corresponds or corresponds essentially to the genomic RNA of SFV or an attenuated form thereof, wherein the open reading frame encoding structural proteins is replaced by an open reading frame encoding the peptide or protein comprising an antigen or epitope,

wherein the antigen or the peptide or protein comprising an antigen or epitope is not a membrane protein, and/or

wherein the antigen is a virus antigen comprising a protein from a virus surface protein comprising a membrane-bound glycoprotein, a viral capsid protein or a spike protein.

7. The composition according to claim 1 , wherein the single stranded RNA and the polyethyleneimine are present in polyplex particles.

8. The composition according to claim 1 , wherein the polyethyleneimine comprises the following general formula (I):

wherein

R is H,

n, is 2; and

p is an integer, and the average molecular weight of the polymer is 1.5·10 2 to 10 7 Da,

wherein at least 92% of the N atoms in the polyethyleneimine are protonatable.

9. The composition according to claim 1 , further comprising one or more additives, wherein the one or more additives are selected from the group consisting of buffering substances, saccharides, stabilizers, cryoprotectants, lyoprotectants, and chelating agents,

wherein the buffering substances comprise at least one selected from the group consisting of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), 2-(N-morpholino)ethanesulfonic acid (MES), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), acetic acid, acetate buffers and analogues, phosphoric acid and phosphate buffers, and citric acid and citrate buffers, and/or

wherein the saccharides comprise at least one selected from the group consisting of monosaccharides, disaccharides, trisaccharides, oligosaccharides, and polysaccharides selected from glucose, trehalose, and saccharose, and/or

wherein the cryoprotectants comprise at least one selected from the group consisting of comprising ethylene glycol, propylene glycol, and glycerol, and/or

wherein the chelating agent comprises EDTA.

10. The composition according to claim 1 , wherein the composition comprises HEPES buffered glucose (HBG), MES-buffered glucose (MBG), Acetate buffered glucose or HEPES buffered trehalose (HBT), wherein the HBG comprises 5% glucose (w/v) and 10 mM HEPES, pH 7.1, and wherein the HBT comprises 10% trehalose (w/v) and 10 mM HEPES, pH 7.1.

11. The composition according to claim 7 , wherein the z-average as derived from dynamic light scattering measurements of the particles is less than 200 nm, and/or the polydispersity index as derived from dynamic light scattering measurements of the particles is less than 0.5, and/or wherein the Zeta-potential of the particles is 20 mV or more, and/or wherein the particles are neutral or positively charged at physiological pH.

12. The composition according to claim 1 , wherein the single stranded RNA is a molecule of 6000 to 15000 bases.

13. A method of treating a disease or condition associated with an immune response comprising administering to a subject in need of treatment the composition according to claim 1 in an amount effective for treatment.

14. The composition according to claim 1 , wherein the composition is a vaccine composition.

15. A method for inducing an immune response in a subject in need thereof, comprising administering to the subject an effective amount of the composition according to claim 1 .

16. The method of claim 15 , wherein the immune response is directed against the antigen or epitope.