Zero-order prolonged release coaxial implants
First Claim
1. A biodegradable coaxial implant in the form of a rod comprising a core comprising active agent to be delivered and a rate-controlling membrane, wherein the rate controlling membrane comprises a polymer selected from the group consisting of polyhydroxyacids, polyanhydrides, polyorthoesters, polyetheresters, polycaprolactone, polyesteramides, polyphosphazenes, polycarbonates, and copolymers and blends thereof, wherein the implant exhibits sustained near zero-order release of an effective amount of the active agent over a period of at least 30 days.
2 Assignments
0 Petitions
Accused Products
Abstract
A coaxial implant has been developed using entirely biodegradable polymeric materials. As referred to herein, a coaxial implant is a device having a core containing drug, surrounded by a semi-permeable membrane that controls the rate of release of material from the core. The device is formed by extrusion, using a pre-milling and extruding step to maximize uniformity of drug dispersion within the polymeric material. In one embodiment, the polymer is processed to yield a semi-crystalline polymer, rather than an amorphous polymer. The core containing the drug and the polymer membrane(s) can be the same or different polymer. The polymer can be the same or different composition (i.e., both polycaprolactone, or both poly(lactide-co-glycolide) of different monomer ratios, or polycaprolactone outside of a core of poly(lactide)), of the same or different molecular weights, and of the same or different chemical structure (i.e., crystalline, semi-crystalline or amorphous). The core acts as a reservoir of drug, which partitions from the core polymer to form a saturated solution of at least 10% drug at the polymer membrane.
-
Citations
23 Claims
- 1. A biodegradable coaxial implant in the form of a rod comprising a core comprising active agent to be delivered and a rate-controlling membrane, wherein the rate controlling membrane comprises a polymer selected from the group consisting of polyhydroxyacids, polyanhydrides, polyorthoesters, polyetheresters, polycaprolactone, polyesteramides, polyphosphazenes, polycarbonates, and copolymers and blends thereof, wherein the implant exhibits sustained near zero-order release of an effective amount of the active agent over a period of at least 30 days.
- 2. A biodegradable coaxial implant in the form of a rod comprising a core comprising active agent to be delivered and a rate-controlling membrane, wherein the rate controlling membrane comprises a polymer selected from the group consisting of polyhydroxyacids, polyanhydrides, polyorthoesters, polyetheresters, polycaprolactone, polyesteramides, polyphosphazenes, polycarbonates, and copolymers and blends thereof, wherein the core of the implant is formed of a crystalline, semicrystalline, or amorphous biodegradable polymer having active agent incorporated therein and, wherein the implant exhibits sustained near zero-order release of an effective amount of the active agent over a period of at least 30 days.
Specification