Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
191 words
An ocular osmotic device sized and adapted for the administration of a beneficial drug, said ocular device comprising: (a) a shaped wall formed of a semipermeable non-toxic material that maintains its integrity during the administering period, is permeable to the passage of eye fluid and substantially impermeable to the passage of drug, said wall surrounding and forming; (b) a compartment containing drug; (c) a layer of a non-toxic, inert bioerodible material on the exterior surface of the semipermeable wall; (d) a passageway in the wall, said passageway communicating with the compartment and the exterior of the device for administering drug from the device; and, (f) wherein, when the device is in the environment of use, the layer bioerodes at a controlled rate to regulate the amount of eye fluid available to the wall, which eye fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby continuously dissolving drug which is administered through the passageway from the device at a controlled rate over a prolonged period of time.
Claim 2
Dependent Claim
191 words
An ocular osmotic device sized and adapted for the administration of a beneficial drug, said ocular device comprising: (a) a shaped wall formed of a semipermeable non-toxic material that maintains its integrity during the administering period, is permeable to the passage of eye fluid and substantially impermeable to the passage of drug, said wall surrounding and forming; (b) a compartment containing drug; (c) a layer of a non-toxic, inert bioerodible material on the exterior surface of the semipermeable wall; (d) a passageway in the wall, said passageway communicating with the compartment and the exterior of the device for administering drug from the device; and, (f) wherein, when the device is in the environment of use, the layer bioerodes at a controlled rate to regulate the amount of eye fluid available to the wall, which eye fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby continuously dissolving drug which is administered through the passageway from the device at a controlled rate over a prolonged period of time.
Claim 3
Dependent Claim
19 words
The ocular device according to claim 1, wherein the layer is substantially impermeable to the passage of eye fluid.
Claim 4
Dependent Claim
29 words
The ocular device according to claim 1, wherein the layer is permeable to eye fluid and surface bioerodes to regulate the amount of eye fluid presented to the wall.
Claim 5
Dependent Claim
135 words
The ocular device according to claim 1, wherein the passageway has a maximum cross-sectional area, A s , defined by ##EQU22## wherein L is the length of the passageway, (Q p /t) is the mass of the drug released per unit time, D is the diffusion coefficient of drug in the released solution, S is the solubility of drug in eye fluid, and F has a value of from 2 to 1000, said passageway having a minimum area, A s defined by ##EQU23## wherein L is the length of the passageway, (v/t) is the volume of drug released per unit time, π is 3.14, η is the viscosity of drug solution released, and ΔP is the hydrostatic pressure difference between the inside and the outside of the compartment having a value up to 20 atmospheres.
Claim 6
Dependent Claim
42 words
The ocular osmotic device according to claim 1, wherein the device is designed, sized and adapted for administering locally and systemically acting drugs to the environment of the eye, and the layer bioerodes in tear fluid to continuously expose the semipermeable wall.
Claim 7
Dependent Claim
29 words
The ocular device according to claim 1, wherein the compartment additionally contains an osmotically effective solute that exhibits an osmotic pressure gradient across the semipermeable wall against the fluid.
Claim 8
Dependent Claim
34 words
The ocular device according to claim 1, wherein the drug is a member selected from the group consisting of pilocarpine, pilocarpine hydrochloride, pilocarpine nitrate, tetracycline, bacitracin, chlorotetracycline, erythromycin, iodoxuridine, hydrocortisone, eserine and phospholine iodine.
Claim 9
Dependent Claim
29 words
The ocular device according to claim 1, wherein the wall is formed of a material selected from the group consisting of cellulose acetate, methyl cellulose, poly-vinyl alcohol and polyurethane.
Claim 10
Dependent Claim
30 words
The ocular device according to claim 1, wherein the layer is formed of a material selected from the group consisting of poly(carboxylic acid), poly(acrylic acid), poly(glycolic acid), and poly(lactic acid).
Claim 11
Dependent Claim
40 words
The osmotic ocular device for the administration of beneficial drug according to claim 1, wherein the device has a length of 4 to 20 millimeters, a width of 1 to 15 millimeters, and a thickness of 0.1 to 4 millimeters.