Details for Patent: 6,372,258

Title:	Methods of spray-drying a drug and a hydrophobic amino acid
Abstract:	According to the subject invention, dispersible dry powder pharmaceutical-based compositions are provided, including methods for their manufacture and dry powder dispersion devices. A dispersible dry powder pharmaceutical-based composition is one having a moisture content of less than about 10% by weight (% w) water, usually below about 5% w and preferably less than about 3% w; a particle size of about 1.0-5.0 .mu.m mass median diameter (MMD), usually 1.0-4.0 .mu.m MMD, and preferably 1.0-3.0 .mu.m MMD; a delivered dose of about >30%, usually >40%, preferably >50%, and most preferred >60%; and an aerosol particle size distribution of about 1.0-5.0 .mu.m mass median aerodynamic diameter (MMAD), usually 1.5-4.5 .mu.m MMAD, and preferably 1.5-4.0 MMAD. Such composition are of pharmaceutical grade purity.
Inventor(s):	Platz; Robert M. (Half Moon Bay, CA), Patton; John S. (San Carlos, CA), Foster; Linda (Sunnyvale, CA), Eljamal; Mohammed (San Jose, CA)
Assignee:	Inhale Therapeutic Systems (San Carlos, CA)
Filing Date:	Nov 22, 1999
Application Number:	09/447,753
Claims:	1. A method for spray-drying a pharmaceutical-based dry powder, said method comprising: providing a mixture of a drug and a hydrophobic amino acid in a suitable solvent, and spray-drying the mixture under conditions effective to provide a respirable dry powder comprising particles, wherein at least about 95% of the mass of the powder has a particle size below 10 .mu.m. 2. The method of claim 1, wherein said solvent is water. 3. The method of claim 1, wherein said hydrophobic amino acid is selected from the group consisting of tryptophan, tyrosine, leucine, and phenylalanine. 4. The method of claim 1, wherein a pharmaceutically-acceptable carrier is also provided in said providing step. 5. The method of claim 4, wherein the carrier comprises a carbohydrate bulking agent. 6. The method of claim 4, wherein the carrier comprises human serum albumin. 7. The method of claim 5, wherein the bulking agent is mannitol. 8. The method of claim 1, wherein about 80% of the mass of the spray-dried powder has a particle size of less than 5 .mu.m. 9. The method of claim 1, wherein the particles have an aerosol particle size distribution of about 1.0-5.0 .mu.m MMAD. 10. The method of claim 1, wherein the hydrophobic amino acid is leucine. 11. The method of claim 1, wherein the spray-dried powder is further characterized by a delivered dose of greater than about 30%. 12. A method for spray-drying a pharmaceutical-based dry powder, said method comprising: providing a mixture of a drug and a hydrophobic amino acid in a suitable solvent, and spray-drying the mixture under conditions effective to provide a respirable dry powder comprising particles having an aerosol particle size distribution of about 1.0-5.0 .mu.m MMAD.