Patents Examined by Andy Griffis
  • Patent number: 4946683
    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.
    Type: Grant
    Filed: August 4, 1989
    Date of Patent: August 7, 1990
    Assignee: Vestar, Inc.
    Inventor: Eric A. Forssen