Implantable devices for drug delivery with reduced burst release

Abstract

The invention provides implantable drug delivery devices comprising a core comprising a polymer (or polymer blend) and one or more drugs or pharmaceutical substances, and an outer shell comprising a polymer (or polymer blend) and one or more porogen materials. The invention reduces burst release of drug. Pharmaceuticals such as triiodothyronine (T3) or ropinirole can be delivered by the devices.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This patent application claims priority benefit of U.S. Provisional Patent Application No. 62 / 404,643 filed Oct. 5, 2016. The entire contents of that application are hereby incorporated by reference herein.TECHNICAL FIELD[0002]The invention provides devices which can be implanted into a patient for release of pharmaceutical substances, such as triiodothyronine, over long periods of time, with reduced, minimal, or no burst release.BACKGROUND OF THE INVENTION[0003]Many patients require long-term, regular dosing with drugs or pharmaceutical substances. Effective treatment often necessitates the ingestion of one or more tablets per day for extended periods of time. For example, patients who undergo thyroidectomy, a common treatment for thyroid cancer, must take oral thyroxine tablets for the rest of their lifetime. Typically, patients take levothyroxine (T4), which is converted in vivo into triiodothyronine (T3). Both T4 and T3 regulate a wid...

AI Technical Summary

Benefits of technology

The invention provides implantable drug delivery devices that use a porogen material to control the release rate of drugs from the device. This helps to reduce the burst release often observed with sustained release formulations and allows better control and tuning of the drug release. The devices consist of a core containing drugs or pharmaceutical substances and a porogen-containing shell. The use of a porogen material with a narrow size distribution further enhances the control of the drug release rate.

Problems solved by technology

Several problems can arise during long-term administration of drugs taken orally or by other routes requiring frequent administration.

Compliance with an extended dosing regimen can often be inconvenient or difficult.

For example, patients with impaired cognitive function (due to Alzheimer's disease or other disorders) may not be able to self-administer drugs reliably, requiring a caregiver to ensure that medications are taken properly.

Frequent or periodic administration, such as would occur with daily oral and sublingual delivery, can result in blood concentrations of drug peaking quickly after initial administration, then dropping steeply before the next administration.

One difficulty encountered with virtually all sustained drug formulations, including implants, is burst release.

Burst release is a high release of drug when the formulation is first administered which is higher than the desired release rate, and which can cause deleterious pharmacological effects resulting from excessive levels of drug.

This is particularly undesirable for systems, such as implants, that release thyroid hormones, as dangerous cardiac complications may occur.

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