Patent · US Expired

Multiple step entrapment/loading procedure for preparing lipophilic drug-containing liposomes

US4946683A · kind A · utility

105Cited by
16References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 4, 1989
Grant dateAug 7, 1990
Priority date
Expiry dateAug 4, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/2984
  • WIPO fieldPharmaceuticals
  • WIPO sectorChemistry

Abstract

Novel liposome-entrapped cationic, lipophilic drug compositions, e.g., anthracycline antineoplastic agent compositions, and multistep entrapment/loading procedures for preparing them are disclosed. These procedures involve forming liposomes from phospholipids, such as distearoyl phosphatidylcholine or a similar long chain fatty acid diester phospholipid, to be loaded with the drug, e.g., daunorubicin or doxorubicin, in aqueous medium in the presence of an acid, e.g., an organic acid which can be monofunctional pyranosidyl acid such as lactobionic acid, adding the drug, and then adding a base such as calcium carbonate whose cations cannot pass through the vesicles' bilayers to charge neutralize the organic acid anions in the external aqueous phase and induce the acid anions in the internal aqueous phase to become neutralized by attracting the cationic, lipophilic drug.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.