Claims for Patent: 4,933,360

Summary for Patent: 4,933,360

Title:	Novel chlorthalidone process and product
Abstract:	Water-soluble dispersions of chlorthalidone are prepared by a process comprising: (a) forming a solution comprising a water soluble pharmaceutically acceptable polymeric carrier and a C.sub.1 -C.sub.4 alkanol, (b) dissolving chlorthalidone in the solution thus formed, and (c) removing the C.sub.1 -C.sub.4 alkanol from the solution by evaporation, the amount of said carrier being effective to suppress substantially the formation of the alkyl ether by-product from the reaction of chlorthalidone with the C.sub.1 -C.sub.4 alkanol. A preferred water soluble carrier is polyvinylpyrrolidone and a preferred C.sub.1 -C.sub.4 alkanol is methanol.
Inventor(s):	Pandit; Nivedita (Middlebury, CT), Horhota; Stephen T. (Brookfield, CT)
Assignee:	Boehringer Ingelheim Pharmaceuticals, Inc. (Ridgefield, CT)
Application Number:	06/796,467
Patent Claims:	1. A process for preparing a water soluble pharmaceutically acceptable solid state dispersion of chlorthalidone which comprises: (a) forming a solution of polyvinylpyrrolidone in a C.sub.1 -C.sub.4 alkanol, (b) dissolving chlorthalidone in the solution thus formed, and (c) removing the C.sub.1 -C.sub.4 formed from the solution by evaporation, the ratio by weight of polyvinylpyrrolidone to chlorthalidone in the dispersion being in the range of from 1:4 to 1:05. 2. A process as defined in claim 1 wherein the C.sub.1 -C.sub.4 alkanol is methanol. 3. A process as defined in claim 1 wherein the ratio by weight of polyvinylpyrrolidone to chlorthalidone is from 1:3 to 1:2. 4. A process as defined in claim 2 wherein the methanol is evaporated from the solution by spray coating the solution onto lactose particles. 5. A solid state dispersion of chlorthalidone produced by the process of claim 1. 6. A pharmaceutically acceptable diuretic tablet composition comprising: (a) a diuretic effective amount of a solid state dispersion of chlorthalidone spray coated onto lactose particles according to the process of claim 4, and (b) a pharmaceutically acceptable tableting excipient. 7. A method of inducing diuresis in the warm-blooded animal comprising administering to said animal a solid state dispersion of chlorthalidone as defined in claim 5, the amount of chlorthalidone in said dispersion being effective for inducing diuresis. 8. A process as defined in claim 3 wherein the C.sub.1 -C.sub.4 alkanol is methanol. 9. A process as defined in claim 8 wherein the methanol is evaporated from the solution by spray coating the solution onto lactose particles. 10. A solid state dispersion of chlorthalidone as defined in claim 5 wherein the dispersion is produced by the process of claim 8. 11. A solid state dispersion of chlorthalidone as defined in claim 5 wherein the dispersion is produced by the process of claim 9.