Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
176 words
A controlled absorption quinidine formulation for oral administration, comprising a pellet having a core of an active ingredient in association with an organic acid, and a membrane of a film-forming polymer or mixture thereof which permits release of the active ingredient at a controlled rate in an aqueous medium, characterised in that the active ingredient is quinidine or a pharmaceutically acceptable salt thereof and in that said pellet has a dissolution rate which is substantially pH independent and which when measured in a Basket Assembly according to U.S. Pharmacopoeia XXI at 37°C and 75 r.p.m has the following. characteristics: a) from 0 to 15% of the total quinidine is released after one hour of measurement in said assembly; b) from 30 to 50% of the total quinidine is released after four hours of measurement in said assembly; c) from 55 to 80% of the total quinidine is released after eight hours of measurement in said assembly; and d) not less than 90% of the total quinidine is released after twenty-four hours of measurement in said assembly.
Claim 2
Dependent Claim
176 words
A controlled absorption quinidine formulation for oral administration, comprising a pellet having a core of an active ingredient in association with an organic acid, and a membrane of a film-forming polymer or mixture thereof which permits release of the active ingredient at a controlled rate in an aqueous medium, characterised in that the active ingredient is quinidine or a pharmaceutically acceptable salt thereof and in that said pellet has a dissolution rate which is substantially pH independent and which when measured in a Basket Assembly according to U.S. Pharmacopoeia XXI at 37°C and 75 r.p.m has the following. characteristics: a) from 0 to 15% of the total quinidine is released after one hour of measurement in said assembly; b) from 30 to 50% of the total quinidine is released after four hours of measurement in said assembly; c) from 55 to 80% of the total quinidine is released after eight hours of measurement in said assembly; and d) not less than 90% of the total quinidine is released after twenty-four hours of measurement in said assembly.
Claim 3
Dependent Claim
55 words
A formulation according to Claim 1, wherein the organic acid is selected from one or more of the following acids: adipic acid, ascorbic acid, citric acid, fumaric acid, malic acid, succinic acid or tartaric acid, the quinidine or pharmaceutically acceptable salt thereof and organic acid being present in a ratio of from 1:1 to 10:1.
Claim 4
Dependent Claim
53 words
A formulation according to Claim 1 or 2, characterised in that the core comprises quinidine or a pharmaceutically acceptable salt thereof, preferably quinidine sulphate, and the associated organic acid embedded in a polymeric material, the core preferably including one or more additional components selected from a lubricant, a dispersing agent and a surfactant.
Claim 5
Dependent Claim
52 words
A formulation according to Claim 3, characterised in that the polymeric material in which the quinidine or pharmaceutically acceptable salt thereof is embedded is rapidly soluble in water, preferably hydroxypropylmethylcellulose or polyvinylpyrrolidone, or, alternatively, is freely permeable to quinidine and water and preferably comprises a copolymer of acrylic and methacrylic acid esters.
Claim 6
Dependent Claim
48 words
A formulation according to Claim 4, wherein the polymeric material includes a minor proportion of a water insoluble polymer, preferably methylcellulose, ethylcellulose, propylcellulose or shellac, or alternatively, a polymer which is slightly permeable to quinidine and water and preferably comprises a copolymer of acrylic and methacrylic acid esters.
Claim 7
Dependent Claim
44 words
A formulation according to any one of Claims 3 to 5, wherein the quinidine, organic acid and polymeric material are built up on an inert core, said inert core preferably comprising a non-pareil seed having an average diameter of from 0.3 to 0.7 mm.
Claim 8
Dependent Claim
60 words
A formulation according to any preceding claim, wherein the membrane has a major proportion of a water insoluble polymer, which is preferably shellac or ethylcellulose, and a minor proportion of a water soluble polymer, which is preferably polyvinylpyrrolidone or hydroxypropylmethylcellulose, the ratio of water insoluble to water soluble polymer being determined by the. inherent solubility characteristics of the respective polymers.
Claim 9
Dependent Claim
91 words
A pellet formulation according to any one of Claims 1 to 6, wherein the membrane is composed of a major proportion of a polymer which is slightly permeable to quinidine and water and a minor proportion of a polymer which is freely permeable to quinidine and water, the ratio of slightly permeable to freely permeable polymer being determined by the inherent permeability of the respective polymers, and each of the slightly permeable and freely permeable polymers preferably comprises a copolymer of acrylic and methacrylic acid esters having the desired permeability characteristics.
Claim 10
Dependent Claim
67 words
A process for the production of a pellet formulation according to any one of Claims 1-8, which comprises forming a core of quinidine or a pharmaceutically acceptable salt thereof and an organic acid and enclosing the core in a membrane of a film-forming polymer or mixture thereof which permits release of the quinidine or the pharmaceutically acceptable salt thereof in the manner set out in Claim 1.
Claim 11
Dependent Claim
19 words
A capsule or tablet characterised in that it comprises pellets according to any one of Claims 1 to 8.