Dry powder pharmaceutical compositions comprising surfactants, hydrophobic active principles, and water-soluble excipients, process of preparing, and stable aqueous suspensions thereof
Pharmaceutical composition in a dry powder form comprising at least one hydrophobic active principle, at least one water-soluble excipient and at least one surfactant, wherein the particles in said dry powder state have a Volume Mean Diameter VMD d greater than the Volume Mean Diameter VMD w of particles in a suspension obtained from said pharmaceutical composition at standard conditions of dispersion in a water-medium. It is also disclosed a process to prepare such dry composition and an extemporaneous suspension for inhalation therapy obtainable from said dry composition.
1. Water suspension of solid particles for oral administration comprising a hydrophobic active principle, obtainable by dispersing in an aqueous medium a dry powder pharmaceutical composition comprising particles comprising said hydrophobic active principle, one or more water soluble excipients and one or more surfactants, characterized in that the Volume Mean Diameter, VMD w , of the particles in said suspension determined under standard conditions of dispersion is lower than the Volume Mean Diameter, VMD d , of the particles in said dry powder composition, the size distribution of the particles in dry powder form and in the suspension is monomodal, and that said surfactant and said active principle have a weight-to-weight ratio from 0.6 to 40 in said dry powder composition.
2. The water suspension according to claim 1 , wherein the complete sedimentation time of said suspension is greater than 40 minutes.
3. The water suspension according to claim 2 , wherein the complete sedimentation time of said suspension is greater than 60 minutes.
4. The water suspension according to claim 3 , wherein the complete sedimentation time of said suspension is greater than 100 minutes.
5. The water suspension according to claim 1 , wherein the theoretical mean diameter TMD of said particles is lower than the Volume Mean Diameter, VMD w .
6. The water suspension according to claim 5 , wherein the theoretical mean diameter, TMD, of said particles fulfils the equation TMD≦0.5 VMD w .
7. The water suspension according to claim 1 , wherein said active principle is a steroid molecule.
8. The water suspension according to claim 7 , wherein said active principle is a glucocorticosteroid.
9. The water suspension according to claim 8 , wherein said glucocorticosteroid is selected from the group consisting of budesonide, beclomethasone, fluticasone propionate, and mixtures thereof.
10. Kit of products for an extemporaneous preparation of a liquid suspension of a hydrophobic active principle, characterized by comprising:
a) an effective amount of a dry powder pharmaceutical composition comprising particles comprising said hydrophobic active principle, at least one water-soluble excipient and at least one surfactant, in which said surfactant and said active principle have a weight-to-weight ratio from 0.6 to 40,
b) a predetermined volume of an aqueous dispersing medium; wherein said products a) and b) are packaged in physically separated containers, in order to be mixed extemporaneously to form a suspension, in which the particles' Volume Mean Diameter, VMD w , measured in standard conditions of dispersion is lower than the Volume Mean Diameter, VMD d , of the particles in said dry powder pharmaceutical composition, and the size distribution of the particles in dry powder form and in the suspension is monomodal.
11. The kit of products according to claim 10 , wherein the Volume Mean Diameter VMD d of the particles in said dry powder composition is from 0.1 to 175 μm.
12. The kit of products according to claim 11 , wherein the Volume Mean Diameter VMD d of the particles in said solid dry composition is from 0.5 to 30 μm.
13. The kit of products according to claim 12 , wherein the Volume Mean Diameter VMD d of the particles in said solid dry composition is from 1 to 10 μm.