Method for making a microsealed delivery device

• US 3,992,518 A
• Filed: 09/29/1975
• Issued: 11/16/1976
• Est. Priority Date: 10/24/1974
• Status: Expired due to Term

• Current Assignee: GD Searle LLC (Pfizer Inc.)
• Original Assignee: GD Searle LLC (Pfizer Inc.)
• Inventors: Chien, Yie W., Lambert, Howard J.
• Primary Examiner(s): Rose, Shep K.
• Application Number:
  US05/617,542
• Time in Patent Office: 414 Days
• Field of Search: 424/19-22, 424/32, 424/78, 424/184, 128/260
• US Class Current: 424/425
• CPC Class Codes: A61K 9/0024 Solid, semi-solid or solidifying implants, which are implanted or injected in body tissue compositions for intravenous administration, normal injectable solutions or dispersions for, e.g. subcutaneous administration A61K9/0019; brain implants A61K9/0085; (coated) prostheses, catheters or stents A61L
• 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 9/0092 Hollow drug-filled fibres, tubes of the core-shell type, coated fibres, coated rods, microtubules or nanotubes
• CPC Class Codes: A61K 9/2036 Silicones; Polysiloxanes

Abstract

The present invention is concerned with a pharmaceutical delivery device comprising a biologically acceptable silicone polymer matrix having microsealed compartments of 10-200 microns throughout, wherein the microsealed compartments contain a pharmaceutical in a hydrophilic solvent system. The biologically acceptable silicone polymer matrix is formed by in situ cross linking of a liquid, biologically acceptable silicone polymer in an emulsion of pharmaceutical in the hydrophilic solvent system and liquid biologically acceptable silicone polymer. The biologically acceptable silicone polymer matrix is placed in a sealed or unsealed biologically acceptable polymer container. The rate of release of pharmaceutical is controlled by altering the solubility characteristics of the hydrophilic solvent system and/or the biologically acceptable polymer matrix, the rate of release being independent of time when the ratio of the partition coefficient of the pharmaceutical between the hydrophilic solvent system and biologically acceptable silicone polymer matrix to the solubility of the pharmaceutical in the hydrophilic solvent system is between 1 and 10^-4 ml/mcg.

Claims

1. a method for constructing a biologically acceptable silicone polymer matrix adapted for placement in silicone polymer or ethylene/vinylacetate copolymer tubing having 10-200 micron microsealed compartments distributed throughout, said microsealed compartments containing a pharmaceutical in a hydrophilic solvent system impermeable to said polymer tubing, comprising:

a. emulsifying the hydrophilic solvent system of water and liquid polyethylene glycol containing the pharmaceutical and biologically acceptable room-temperature Vulcanizing liquid polydimethylsiloxane silicone polymer and

b. in situ cross-linking the biologically acceptable liuqid silicone polymer to form the biologically acceptable silicone polymer matrix with microsealed compartments throughout containing pharmaceutical and hydrophilic solvent system.