Tiotropium formulation and inhaler

1. A metered dose inhaler equipped with a metering valve and having an aerosol canister containing a pharmaceutical composition comprising:

propellant;

ethanol at a concentration of no greater than about 20 wt. %;

citric acid at a concentration of no greater than 0.07 wt. %; and

tiotropium or a pharmaceutically acceptable salt or solvate thereof dissolved in the composition;

wherein the aerosol canister has an internal surface that is a non-metal material that is in contact with the pharmaceutical composition,

wherein the pharmaceutical composition does not include water.

2. The metered dose inhaler of claim 1 , wherein the pharmaceutical composition comprising tiotropium or a pharmaceutically acceptable salt or solvate thereof is tiotropium bromide.

3. The metered dose inhaler of claim 1 , wherein the propellant comprises 1,1-difluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, or combinations thereof.

4. The metered dose inhaler of claim 1 , wherein the propellant consists essentially of 1,1,1,2-tetrafluoroethane.

5. The metered dose inhaler of claim 1 , wherein the concentration of the tiotropium is between about 0.07 mg/mL and 0.15 mg/mL.

6. The metered dose inhaler of claim 1 , wherein the concentration of the tiotropium is between about 0.09 mg/mL and 0.13 mg/mL.

7. The metered dose inhaler of claim 1 , wherein the concentration of the citric acid is between about 0.02 wt. % and 0.06 wt %.

8. The metered dose inhaler of claim 1 , wherein the concentration of the citric acid is about 0.04 wt. %.

9. The metered dose inhaler of claim 1 , wherein in the concentration of the ethanol is about 15 wt. %.

10. The metered dose inhaler of claim 1 , wherein a metered dose is of between 3 micrograms and 6 micrograms per actuation.

11. The metered dose inhaler of claim 1 , wherein the non-metal material comprises a silane primer composition having two or more reactive silane groups separated by an organic linker group disposed thereon, wherein the silane primer composition has a coating composition comprising an at least partially fluorinated compound disposed thereon.

12. The metered dose inhaler of claim 1 , wherein the non-metal material comprises a polyfluoropolyether silane.

13. The metered dose inhaler of claim 1 , wherein the non-metal material comprises a fluorinated ethylene propylene (FEP) copolymer.

14. The metered dose inhaler of claim 1 , wherein the propellant consists essentially of 1,1-difluoroethane.

15. The metered dose inhaler of claim 1 , wherein the non-metal material comprises a polyphenylsulphone.

16. The metered dose inhaler of claim 1 , wherein the composition loses less than 5 wt. % of the tiotropium content after six months of storage inside an aerosol canister at a temperature of 25° C. and a relative humidity of 60%.

17. The metered dose inhaler of claim 1 wherein the metering valve is at least partially coated on its interior surface with a non-metal material.

18. The metered dose inhaler of claim 17 , wherein the non-metal material comprises a silane primer composition having two or more reactive silane groups separated by an organic linker group disposed thereon, wherein the silane primer composition has a coating composition comprising an at least partially fluorinated compound disposed thereon.

19. A metered dose inhaler equipped with a metering valve and having an aerosol canister containing a pharmaceutical composition consisting of:

propellant;

ethanol at a concentration of no greater than about 20 wt. %;

citric acid at a concentration of no greater than 0.07 wt. %; and

tiotropium or a pharmaceutically acceptable salt or solvate thereof dissolved in the composition;

wherein the aerosol canister has an internal surface that is a non-metal material that is in contact with the pharmaceutical composition.