High drug:lipid formulations of liposomal antineoplastic agents
US5616341A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1993 |
| Grant date | Apr 1, 1997 |
| Priority date | — |
| Expiry date | Aug 26, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2984
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A method for encapsulation of antineoplastic agents in liposomes is provided, having preferably a high drug:lipid ratio. Liposomes may be made by a process that loads the drug by an active mechanism using a transmembrane ion gradient, preferably a transmembrane pH gradient. Using this technique, trapping efficiencies approach 100%, and liposomes may be loaded with drug immediately prior to use, eliminating stability problems related to drug retention in the liposomes. Drug:lipid ratios employed are about 3-80 fold higher than for traditional liposome preparations, and the release rate of the drug from the liposomes is reduced. An assay method to determine free antineoplastic agents in a liposome preparation is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.