Method and formulation for inhalation
This invention relates to drug delivery and in particular to the delivery of biologically active agents in the form of dry powders for inhalation. The invention also relates to methods for preparing such dry powder formulations and methods for their use.
1. A method for the treatment or prevention of post partum haemorrhage comprising administering to a subject in need thereof an inhalable dry powder, wherein said inhalable dry powder comprises spray dried particles comprising
(a) oxytocin or carbetocin,
(b) L-leucine, the L-leucine being present in the amount from 10 to 40% by weight based on the dry weight of said spray dried particles excluding the weight of oxytocin or carbetocin, and
(c) the weight remainder of said spray dried particles being an amorphous glass matrix consisting essentially of trehalose, and the oxytocin or carbetocin being dispersed within the amorphous glass matrix, and
wherein the inhalable dry powder is prepared by a process comprising: preparing an aqueous solution or suspension comprising oxytocin or carbetocin, trehalose, and L-leucine; and spray drying the aqueous solution or suspension to produce the inhalable dry powder, and the amount of dry powder administered is sufficient to provide a dose of oxytocin or carbetocin that provides an effective and rapid onset of action for treating or preventing post partum haemorrhage, and said dose is about 200 IU.
2. The method according to claim 1 wherein the inhalable dry powder is for nasal administration.
3. The method according to claim 1 wherein the inhalable dry powder is for inhalation into the pulmonary system via the mouth.
4. The method according to claim 1 wherein at least a portion of the L-leucine is located at the surface of the particles of the dry powder.
5. The method according to claim 1 , wherein more than 40% of the particles of the dry powder upon inhalation have an aerodynamic diameter of less than 5 μm.
6. The method according to claim 1 wherein the oxytocin is about 1.0% of the entire powder content.
7. The method according to claim 1 wherein the spray drying is carried out at a temperature below 80° C.
8. The method according to claim 1 wherein the rapid onset of action following inhalation of the dry powder, as measured by uterine contraction, is achieved within 200 seconds of inhalation.
9. The method according to claim 8 wherein the rapid onset of action is achieved within 150 seconds of inhalation.
10. The method according to claim 9 wherein the rapid onset of action is achieved within 100 seconds of inhalation.
11. The method according to claim 1 wherein the inhalable dry powder further comprises a stabilizer.
12. The method according to claim 11 dry powder contains a stabilizer, wherein said stabilizer comprises sodium citrate.
13. The method according to claim 1 , wherein the amorphous glass matrix is in an amount of 90%.
14. The method according to claim 1 , wherein the amorphous glass matrix is in an amount between 80%-90% of the spray dried particles.