Controlled release aqueous emulsion
US5672358A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 1995 |
| Grant date | Sep 30, 1997 |
| Priority date | — |
| Expiry date | Jun 19, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/0095
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A controlled release aqueous emulsion is disclosed, as are its method of manufacture and use as a vehicle for delivering medicaments in liquid form. A contemplated emulsion comprises an oil-in-water emulsion having an average oil particle size of about 100 nm to about 250 nm, a pH value of about 4.5 to about 8.0 and a viscosity at 20.degree.-25.degree. C. of 1 to about 1000 cps. The water phase constitutes at least 25 weight percent of the total composition. The oil phase is a wax matrix that is a wax having a melting point of about 40.degree. to about 80.degree. C. and is present in an amount of about 3 to about 30 percent of the total composition. A pharmaceutically effective amount of a pharmacologically active compound that is free from decomposition at a temperature below about 90.degree. C. is dissolved or dispersed in the wax matrix. The oil and water phases are emulsified by an emulsifying agent that provides freedom from phase separation at a pH value of about 4.5 to about 8, while also providing phase separation at a pH value below about 2.0. The emulsifier, based on lecithin, is present at about 2 to about 20 weight percent of the total composition. The composition can a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.