Therapeutic system for administering drugs to the skin

• US 4,286,592 A
• Filed: 02/04/1980
• Issued: 09/01/1981
• Est. Priority Date: 02/04/1980
• Status: Expired due to Term

• Current Assignee: ALZA Corporation (Johnson & Johnson)
• Original Assignee: ALZA Corporation (Johnson & Johnson)
• Inventors: Chandrasekaran, Santosh K.
• Primary Examiner(s): ROSENBAUM, C FRED
• Application Number:
  US06/117,846
• Time in Patent Office: 575 Days
• Field of Search: 128/155-156, 128/270, 128/260
• US Class Current: 424/448
• CPC Class Codes: A61F 13/00063 comprising medicaments or additives, e.g. odor control, PH control, debriding, antimicrobic drug delivery dressings A61K9/70; chemical aspect of the additives A61L15/00
• CPC Class Codes: A61F 13/0256 characterized by the parametric properties of the adhesive
• CPC Class Codes: A61F 13/8405 Additives, e.g. for odour, disinfectant or pH control
• CPC Class Codes: A61F 2013/00906 for transcutaneous or transdermal drugs application
• CPC Class Codes: A61F 2013/51409 being a film
• CPC Class Codes: A61K 9/006 Oral mucosa, e.g. mucoadhesive forms, sublingual droplets; Buccal patches or films; Buccal sprays
• CPC Class Codes: A61K 9/7053 obtained by reactions only involving carbon to carbon unsaturated bonds, e.g. polyvinyl, polyisobutylene, polystyrene
• CPC Class Codes: A61K 9/7084 Transdermal patches having a drug layer or reservoir, and one or more separate drug-free skin-adhesive layers, e.g. between drug reservoir and skin, or surrounding the drug reservoir; Liquid-filled reservoir patches

Abstract

A bandage for administering drugs to the skin that consists of an impermeable backing layer, a drug reservoir layer composed of drug and a carrier, and a contact adhesive layer by which the bandage is adhered to the skin. The contact adhesive layer controls the rate at which drug is administered and maintains that rate at an approximately constant level by virtue of there being a particular correlation between the solubility of the drug in the carrier and in the contact adhesive, the diffusion coefficient of the drug in the carrier and in the contact adhesive, the concentration of drug in the reservoir, and the thickness of the contact adhesive layer.

Claims

1. A bandage for administering a drug to the skin or mucosa for a predetermined time period, with t representing a time, in hours, in said time period, consisting essentially of a sandwich type laminate of:

(a) a backing lamina that is substantially impermeable to the drug, one face of which forms the top of the bandage;

(b) a drug reservoir lamina adjacent the opposite face of the backing lamina comprising the drug dispersed in a carrier that is permeable to the drug, with the solubility of the drug in the carrier being C_SDR mg/cm³, the diffusion coefficient of drug in the carrier being D_DR cm² /hr, and the concentration of drug in the drug reservoir being C_DR mg/cm³ ; and

(c) a contact adhesive lamina adjacent and below the drug reservoir lamina comprising a contact adhesive composition that is permeable to the drug, with the thickness of the contact adhesive lamina being l_CA cm, the solubility of the drug in the contact adhesive composition being C_SCA mg/cm³, the diffusion coefficient of drug in the contact adhesive composition being D_CA cm² /hr, and the concentration of drug in the contact adhesive composition being C_CA mg/cm³, wherein over at least a substantial portion of said time period

(i) C_CA is not greater than C_SCA, and

(ii) the ratio ##EQU3## is in the range of about 0.01 to about 0.7.

2. The bandage of claim 1 wherein the substantial portion of the time period is at least 50% of the time period.

3. The bandage of claim 1 wherein the drug constitutes less than 35% of volume of the reservoir.

4. The bandage of claim 1 wherein

C_SDR is in the range of 0.1 and 100 mg cm³,

C_SCA is in the range of 0.1 and 100 mg cm³,

D_DR is in the range of 1×

10^-11 and 1×

10^-7 cm² /sec,

D_CA is in the range of 1×

10^-11 and 1×

10^-7 cm² /sec,

and l_CA is in the range of 50 microns and 2 mm.

5. The bandage of claim 4 wherein the carrier comprises silicone or a mixture of polyisobutene and mineral oil.