Laminated drug dispenser

• US 3,926,188 A
• Filed: 11/14/1974
• Issued: 12/16/1975
• Est. Priority Date: 11/14/1974
• Status: Expired due to Term

• Current Assignee: Richard Baker, Robert M. Gale
• Original Assignee: Richard Baker, Robert M. Gale
• Inventors: Baker, Richard W., Gale, Robert M.
• Primary Examiner(s): Medbery, Aldrich F.
• Application Number:
  US05/523,720
• Time in Patent Office: 397 Days
• Field of Search: 128/156,260,268,2R,156,213 206/.5 424/19-21
• US Class Current: 424/427
• CPC Class Codes: A61K 9/0004 Osmotic delivery systems; Sustained release driven by osmosis, thermal energy or gas
• CPC Class Codes: A61K 9/0051 Ocular inserts, ocular implants
• CPC Class Codes: A61K 9/0092 Hollow drug-filled fibres, tubes of the core-shell type, coated fibres, coated rods, microtubules or nanotubes
• 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 three layer laminate drug dispenser comprising a core lamina of a crystalline drug of low water solubility dispersed homogeneously in a polymer matrix of permeability, P, to the drug, the lamina having a thickness, 2t, and a surface area, A, interposed between outer laminas made of a drug release rate controlling polymer of permeability, P'"'"''"'"', to the drug, each outer lamina having a thickness, t'"'"''"'"',and the combined, exposed surface area of the outer laminas being A'"'"''"'"' wherein the expression

and the expression

k being a constant whose value is dependent upon the geometrical shape of the dispenser.

Claims

1. An active agent dispenser comprising a laminate of:

a. a core lamina of particles of a crystalline active agent of low water solubility dispersed in a solid material having a permeability, P, to the agent, the core lamina having a thickness 2t, and an exposed surface area, A, from which agent is released, and being partially covered by;

b. at least one outer lamina made of an active agent release rate controlling polymer having a permeability, P'"'"''"'"', to the agent, a thickness, t'"'"''"'"', and an exposed surface area, A'"'"''"'"', from which agent is released wherein

2. The dispenser of claim 1 wherein the agent is a drug.

3. The drug dispenser of claim 2 wherein

4. The drug dispenser of claim 2 wherein P is substantially greater than P'"'"''"'"'.

5. The drug dispenser of claim 4 wherein P is substantially greater than P'"'"''"'"' because of the porosity of the core lamina caused by the quantity of drug therein.

6. The drug dispenser of claim 2 wherein the drug initially comprises 30 to 75% by weight of the core lamina.

7. The drug dispenser of claim 2 wherein the solubility of the drug in water is less than 4% by weight.

8. The drug dispenser of claim 2 wherein the drug is chloramphenicol, physostigmine or hydrocortisone, and the dispenser is sized and shaped for insertion in the cul-de-sac of a human eye.

9. The dispenser of claim 1 wherein the dispenser is a three layer sandwich-type laminate, said core lamina being sandwiched between a pair of said outer lamina.

10. The dispenser of claim 9 wherein the laminate has the geometrical shape of a thin circular disc and k is 8.

11. The dispenser of claim 9 wherein the laminate has the geometrical shape of a thin elliptical disc and k is 4.

12. The dispenser of claim 1 wherein the dispenser is a concentric-type laminate, said outer lamina being outerly concentric to said core lamina and covering the axial surface of said core lamina.

13. The dispenser of claim 12 wherein the laminate is cylindrical in shape and k has a value of 1/8 .