Novel drug delivery device

• US 3,921,636 A
• Filed: 04/22/1974
• Issued: 11/25/1975
• Est. Priority Date: 01/15/1973
• Status: Expired due to Term

• Current Assignee: Alejandro Zaffaroni
• Original Assignee: Alejandro Zaffaroni
• Inventors: Zaffaroni, Alejandro
• Primary Examiner(s): Medbery, Aldrich F.
• Application Number:
  US05/462,895
• Time in Patent Office: 582 Days
• Field of Search: 128/2R,335.5,260,268,270,271,156,130 424/16,19,22,28
• US Class Current: 424/432
• CPC Class Codes: A61F 13/202 Catamenial tampons A61F13/2022-A61F13/34 take precedence
• CPC Class Codes: A61F 13/2051 characterised by the material or the structure of the inner absorbing core
• CPC Class Codes: A61F 13/2074 impregnated with hydrophobic, hydrophilic, skin enhancers, medicinal etc. substances
• CPC Class Codes: A61F 13/84 Accessories, not otherwise provided for, for absorbent pads
• CPC Class Codes: A61F 13/8405 Additives, e.g. for odour, disinfectant or pH control
• CPC Class Codes: A61F 2013/15048 for protection against contamination, or protection in using body disinfecting wipes
• CPC Class Codes: A61F 2013/15113 for haemorrhoids
• CPC Class Codes: A61F 6/14 intra-uterine type
• CPC Class Codes: A61K 9/0036 Devices retained in the vagina or cervix for a prolonged period, e.g. intravaginal rings, medicated tampons, medicated diaphragms
• CPC Class Codes: A61K 9/0039 Devices retained in the uterus for a prolonged period, e.g. intrauterine devices for contraception
• CPC Class Codes: A61K 9/1652 Polysaccharides, e.g. alginate, cellulose derivatives; Cyclodextrin homeopathic globules A61K9/1623
• CPC Class Codes: A61K 9/2081 with microcapsules or coated microparticles according to A61K9/50
• CPC Class Codes: A61K 9/5042 Cellulose; Cellulose derivatives, e.g. phthalate or acetate succinate esters of hydroxypropyl methylcellulose
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50

Abstract

A drug delivery device for administering drug at a controlled rate for a prolonged period of time is disclosed. The device comprises a plurality of reservoirs containing drug distributed through a matrix. The reservoirs and the matrix are formed of materials permeable to passage of drug. The rate of drug permeation (release) from the reservoir is lower than the rate of permeation through the matrix so that release from the reservoir is the drug release rate controlling step.

Claims

1. A drug delivery device which releases drug continuously at a controlled rate over a prolonged period of time when administered to an animal comprising:

a. a plurality of reservoirs each comprising i. a drug confined within ii. a drug release rate controlling material permeable to the drug by diffusion, microporous flow or a combination thereof, said drug release rate controlling material being essentially insoluble in body fluids and essentially non-crushable under the conditions of administration and, with the proviso that if said drug is highly water soluble, substantially impermeable to body fluids;

dispersed in b. a matrix formed of a material permeable to said drug at a rate greater than the rate of permeability of the drug through said drug release rate controlling material so that the rate of drug permeation through said drug release rate controlling material determines the rate of release of drug from the device;

whereby when the device is administered said reservoirs remain intact and release drug by diffusion, microporous flow or a combination thereof continuously at a controlled rate for said prolonged period.

2. The drug delivery device in accordance with claim 1 wherein the reservoir material is essentially imperforate and is permeable to the passage of drug by the process of diffusion.

3. The drug delivery device in accordance with claim 2 wherein the reservoirs are fibers.

4. The drug delivery device in accordance with claim 2 wherein the reservoirs are microcapsules.

5. The drug delivery device in accordance with claim 4 wherein the rate at which the drug permeates the matrix is in the range of from 10 to 2 times as great as the rate at which the drug diffuses through the reservoir material.

6. The drug delivery device in accordance with claim 1 wherein the reservoir material is microporous and is permeable to the passage oF drug by microporous flow through fluid in the micropores.

7. The drug delivery device in accordance with claim 6 wherein the reservoirs are fibers.

8. The drug delivery device in accordance with claim 6 wherein the reservoirs are microcapsules.

9. The drug delivery device in accordance with claim 8 wherein the fluid in the micropores is a body fluid.

10. The drug delivery device in accordance with claim 8 wherein the fluid in the micropores is a specifically added material.

11. The drug delivery device in accordance with claim 1 wherein said reservoirs are distributed homogeneously through said matrix.

12. The drug delivery device in accordance with claim 4 wherein said microcapsules are distributed homogeneously throughout the matrix.

13. An intrauterine drug delivery device comprising a matrix of silicone elastomer having a plurality of drug reservoirs dispersed therethrough, the reservoirs comprising progesterone particles each microencapsulated within a drug release rate controlling polyethylene wall.