Timothy M Devine

US Patent:

58075674, Sep 15, 1998

Filed:

Dec 11, 1996

Appl. No.:

8/763021

Inventors:

Donald A. Randolph - Wheaton IL
Jodi L. Negri - Wildwood IL
Timothy R. Devine - Whitefish Bay WI
Steven Gitelis - Mallard Oak Brook IL

Assignee:

Wright Medical Technology, Incorporated - Arlington TN

International Classification:

A61F 202
A61K 916
A61K 950

US Classification:

424426

Abstract:

This invention relates to the controlled release of calcium sulfate as well as to the controlled release of an additive to a calcium sulfate matrix such as medicaments or pesticides. The controlled release is achieved by a pellet comprising calcium sulfate. The pellet is prepared by the process comprising mixing powder consisting essentially of alpha-calcium sulfate hemihydrate, a solution comprising water, and, optionally, an additive and a powder consisting essentially of beta-calcium sulfate hemihydrate to form a mixture, and forming said mixture into a pellet, wherein said alpha-calcium sulfate hemihydrate and beta-calcium sulfate hemihydrate powders have specified properties such as BET surface areas, densities, mean particle sizes, and purities. The dissolution rate of the calcium sulfate pellet is controlled by varying the weight ratio of the beta-calcium sulfate hemihydrate powder to the alpha-calcium sulfate hemihydrate powder from 0 to about 3. The invention also provides a method of delivering medicament in vivo by implanting a pellet prepared with medicament into a human or an animal.

US Patent:

6030636, Feb 29, 2000

Filed:

Sep 2, 1998

Appl. No.:

9/145671

Inventors:

Donald A. Randolph - Wheaton IL
Jodi L. Negri - Lakevilla IL
Timothy R. Devine - Whitefish Bay WI
Steven Gitelis - Oak Brook IL

Assignee:

Wright Medical Technology Incorporated - Arlington TN

International Classification:

A61F 202
A61K 916
A61K 950

US Classification:

424426

Abstract:

This invention relates to the controlled release of calcium sulfate as well as to the controlled release of an additive to a calcium sulfate matrix such as medicaments or pesticides. The controlled release is achieved by a pellet comprising calcium sulfate. The pellet is prepared by the process comprising mixing powder consisting essentially of alpha-calcium sulfate hemihydrate, a solution comprising water, and, optionally, an additive and a powder consisting essentially of beta-calcium sulfate hemihydrate to form a mixture, and forming said mixture into a pellet, wherein said alpha-calcium sulfate hemihydrate and beta-calcium sulfate hemihydrate powders have specified properties such as BET surface areas, densities, mean particle sizes, and purities. The dissolution rate of the calcium sulfate pellet is controlled by varying the weight ratio of the beta-calcium sulfate hemihydrate powder to the alpha-calcium sulfate hemihydrate powder from 0 to about 3. The invention also provides a method of delivering medicament in vivo by implanting a pellet prepared with medicament into a human or an animal.

US Patent:

56142064, Mar 25, 1997

Filed:

Mar 7, 1995

Appl. No.:

8/399769

Inventors:

Donald A. Randolph - Wheaton IL
Jodi L. Negri - Lakevilla IL
Timothy R. Devine - Whitefish Bay WI
Steven Gitelis - Oakbrook IL

Assignee:

Wright Medical Technology, Inc. - Arlington TN

International Classification:

A61F 202
A61K 916
A61K 950

US Classification:

424426

Abstract:

This invention relates to the controlled release of calcium sulfate as well as to the controlled release of an additive to a calcium sulfate matrix such as medicaments or pesticides. The controlled release is achieved by a pellet comprising calcium sulfate. The pellet is prepared by the process comprising mixing powder consisting essentially of alpha-calcium sulfate hemihydrate, a solution comprising water, and, optionally, an additive and a powder consisting essentially of beta-calcium sulfate hemihydrate to form a mixture, and forming said mixture into a pellet, wherein said alpha-calcium sulfate hemihydrate and beta-calcium sulfate hemihydrate powders have specified properties such as BET surface areas, densities, mean particle sizes, and purifies. The dissolution rate of the calcium sulfate pellet is controlled by varying the weight ratio of the beta-calcium sulfate hemihydrate powder to the alpha-calcium sulfate hemihydrate powder from 0 to about 3. The invention also provides a method of delivering medicament in vivo by implanting a pellet prepared with medicament into a human or an animal.