Sustained release formulation containing an ion-exchange resin

Claim 2

A sustained-release polymeric hydrogel dosage form useful for topical, systemic or transdermal administration of a medicinal agent comprising 50% to 90% w/w of a cross-linked, polymerized hydrophilic polymer, 0.1% to 35% w/w of an ion-exchange resin, which was mixed with the monomer used to form said polymerized hydrophilic monomer prior to polymerization, 0.1% to 20% w/w of a cross-linking agent and said medicinal agent in a therapeutically effective amount.

Claim 3

The sustained-release dosage form of claim 1 wherein the dosage form includes therein a hydrophobic polymer in the amount of about 8% to about 20% w/w.

Claim 4

The sustained-release dosage form of claim 1 or 2 wherein said medicinal agent is an antibiotic, an antiviral, an anti-inflammatory, a steroid, a peptide, a polypeptide, a cardiotonic, an antihypertensive, an antiallergic, an alpha-adrenergic blocking agent, a beta-adrenergic blocking agent, an anti-cataract agent, an ophthalmic medicament, an ophthalmic lubricating agent or an ophthalmic anesthetic agent.

Claim 5

The sustained-release dosage form of claim 1 or 2 wherein said medicinal agent is selected from the group consisting of pilocarpine, idoxuridine, carbachol, bethanechol, timolol, tetracycline, epinephrine, phenylephrine, eserine, phospholine, demecarium, cyclopentolate, homatropine, scopolamine, nitroglycerin, chlortetracycline, bacitracin, neomycin, polymyxin, gramicidin, oxytetracycline, chloramphenicol, gentamycin, penicillin, erythromycin, sulfacetamide, polymyxin B, tobramycin, isofluorophate, fluoromethalone, dexamethasone, hydrocortisone, fluorocinolone, medrysone, prednisolone, methyl prednisolone, betamethasone, triamcinolone, interferon, cromolyn, all trans-retinoic acid and a nontoxic, pharmaceutically acceptable salt thereof.

Claim 6

The sustained-release dosage form of claim 1 or 2 wherein said medicinal agent is an ophthalmic lubricating agent selected from the group consisting of polyvinyl alcohol, a cellulose polymer and a polylactam.

Claim 7

The sustained-release dosage form of claim 1 or 2 wherein said medicinal agent is an ophthalmic anesthetic agent.

Claim 8

The sustained-release dosage form of claim 1 or 2 wherein said dosage form is molded as a contact lens with a clear optical zone or ocular insert for ophthalmic administration of a systemic medicament, an ophthalmic medicament or an ophthalmic lubricating agent.

Claim 9

The sustained-release dosage form of claim 1 of 2 wherein said dosage form is molded as a contact lens with a clear optical zone capable of correcting vision for ophthalmic administration of a systemic medicament, an ophthalmic medicament or an ophthalmic lubricating agent.

Claim 10

A method of administering a therapeutically effective amount of a medicinal agent over an extended period of time to a mammal in need of the medicinal agent for local or systemic effect which comprises contacting a tissue of said mammal with the sustained-release dosage form of claim 1 or 2 for a prolonged period of time.

Claim 11

A method of administering a therapeutically effective amount of an opthalmic medicament over an extended period of time to a mammal in need of the medicament which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2 for a prolonged period of time, wherein said medicinal agent is the ophthalmic medicament.

Claim 12

A method of administering a therapeutically effective amount of an ophthalmic lubricating agent over an extended period of time to a mammal in need of the agent which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2 for a prolonged period of time, wherein said medicinal agent is the ophthalmic lubricating agent.

Claim 13

A method of administering a therapeutically effective amount of an ophthalmic anesthetic agent over an extended period of time to a mammal in need of ophthalmic anesthesia which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2 for a prolonged period of time, wherein said medicinal agent is the ophthalmic anesthetic agent.

Claim 14

A method of treating glaucoma in a mammal suffering from glaucoma which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2, wherein said medicinal agent is an agent for reducing intraocular pressure for a prolonged period of time.

Claim 15

A method of treating glaucoma in a mammal suffering from glaucoma which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2, wherein said medicinal agent is timolol, pilocarpine or a nontoxic, pharmaceutically acceptable salt thereof for a prolonged period of time.

Claim 16

A method of inducing natural lacrimation or creating artificial lacrimation in a mammal suffering from deficient lacrimation which comprises contacting an eye tissue of said mammal with the sustained-release dosage form of claim 1 or 2 for a prolonged period of time, wherein said medicinal agent is an ophthalmic lubricating agent.

Claim 17

A process for the preparation of the sustained-release dosage form of claim 1 which comprises mixing a hydrophilic monomer, an ion-exchange resin and a cross-linking agent, polymerizing the solution into a polymer and soaking the polymer in an aqueous solution or suspension of a therapeutically effective amount of a medicinal agent for a sufficient amount of time for equilibration.

Claim 18

A process for the preparation of the sustained-release dosage form of claim 1 which comprises soaking an ion-exchange resin in an aqueous solution or suspension of a therapeutically effective amount of a medicinal agent for a sufficient amount of time for equilibration, drying the resin, incorporating the resin into a mix of a hydrophilic monomer and a cross-linking agent and polymerizing into a polymer.

Claim 19

A process for the preparation of the sustained-release dosage form of claim 2 which comprises mixing a hydrophilic monomer, an ion-exchange resin, a cross-linking agent and a hydrophobic monomer, polymerizing the solution into a polymer and soaking the polymer in an aqueous solution or suspension of a therapeutically effective amount of a medicinal agent for a sufficient amount of time for equilibration.

Claim 20

A process for the preparation of the sustained-release dosage form of claim 2 which comprises soaking an ion-exchange resin in an aqueous solution or suspension of a therapeutically effective amount of a medicinal agent for a sufficient amount of time for equilibration, drying the resin, incorporating the resin into a mix of a hydrophilic monomer, a cross-linking agent and a hydrophobic monomer and polymerizing into a polymer.

Claim 21

The process of claim 16, 17, 18, or 19 wherein a catalyst is used.

Claim 22

The process of claim 16, 17, 18, or 19 wherein a catalyst and a mold are used.

Claim 23

The process of claim 16, 17, 18, or 19 wherein a catalyst is used and the polymerizing step involves spin casting.

Claim 24

The process of claim 16, 17, 18, or 19 wherein a catalyst and an optical mold are used and the process further comprises a lathing step to form a contact lens with a clear optical zone and the resin with the medicinal agent in the periphery of the lens.