Implantable device for long-term delivery of drugs

摘要

A device for sustained delivery of a poorly water soluble drug is described. A drug reservoir within the device, when in operation, contains an aqueous suspension of the drug mixed with a suspension of an excipient that, in one embodiment, generates acidic groups for a sustained period of time to maintain a desired pH in the aqueous suspension that in turn provides a constant concentration of a soluble form of the drug.

主权项

1. A drug delivery device, comprising:
a non-erodible, non-porous housing member defining a reservoir, said housing member having a water impermeable outer surface and first and second opposing ends; a porous partition positioned in the first end of the housing member; contained within said reservoir, a drug formulation comprised of a sparingly water soluble drug and a solubility-modifying excipient, said sparingly water soluble drug having a soluble form and an insoluble form, wherein the insoluble form of the drug is retained in the reservoir, and wherein said solubility-modifying excipient is capable of generating acid groups to provide a concentration of the drug, in an aqueous suspension when the drug formulation is hydrated, to provide release of a therapeutic dose of the drug from the device over a period of between about 2-12 months, as the soluble form of the drug freely diffuses out of the device across said partition; and wherein release of the therapeutic dose is dependent on pH of the drug formulation and independent of pore size of the porous partition.