pH sensitive, reversible gelling, copolymeric erodible drug delivery system
AssigneeAllergan, Inc.
InventorNienyuan J. Chang
Life of this patent
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Abstract
pH sensitive, reversible gelling erodible drug delivery compositions and methods for their production are disclosed. The compositions are liquid solutions of poly(methylvinylether/maleic acid) having pharmaceutical compounds incorporated therein. The poly(methylvinylether/maleic acid) solutions increase in viscosity with increases in pH. Thus, when the compositions are formulated at a pH lower than physiological pH's, and then delivered to a target physiological site, the liquid solution becomes viscous and adheres to the tissue for a length sufficient to provide prolonged bioavailability of the pharmaceutical compound.
Claims15
A reversible gelling drug delivery composition exhibiting a change in solution viscosity in response to variations in pH value, said composition comprising:
- an aqueous solution of from about 1 w/v% to about 25 w/v% poly(methylvinylether/maleic acid) having a number-averaged molecular weight of from about 20,000 to about 100,000 and from about 0.005 w/v% to about 50 w/v% of a therapeutic or diagnostic pharmaceutical compound, said aqueous solution having a formation pH value of from about 1-4 and said therapeutic or diagnostic pharmaceutical compound being chemically stable in the presence of said poly(methylvinylether/maleic acid).
A pH sensitive reversible gelling drug delivery composition comprising:
- an aqueous solution of from about 2 w/v% to about 10 w/v% poly(methylvinylether/maleic acid) copolymer having a number-averaged molecular weight of from about 20,000 to about 100,000;
- and
- from about 0.05 w/v% to about 0.5 w/v% dipivefrin, said aqueous solution having a formation pH value of from about 1-4.
A process for delivering a therapeutic or diagnostic pharmaceutical compound over an extended period of time to a mammalian physiological site having a pH value of at least about 6, said process comprising the steps of:
- providing an aqueous solution of from about 1 w/v% to about 25 w/v% poly(methylvinylether/maleic acid) having a number-averaged molecular weight from about 20,000 to 100,000 and from about 0.005 w/v% to about 50 w/v% of a therapeutic or diagnostic pharmaceutical compound, said aqueous solution having a pH value of between about 1-4 and said therapeutic or diagnostic pharmaceutical compound being chemically stable in the presence of said poly(methylvinylether/maleic acid);
- and
- introducing said aqueous solution to said mammalian physiological site.
Dependencies are inferred from the claim text.