Osmotic pump drug delivery systems and methods

Abstract

Implantable osmotic pump devices and systems include multiple osmotic pumps and / or semipermeable membranes to extend the useful life cycle and functionality of the drug delivery system. Use of an implantable system including multiple implantable osmotic pumps allows different drugs to be administered from the same implanted system. One or more of the semipermeable membranes of the system may be initially sealed by an overlying impermeable membrane upon implantation of the system into the patient. When the patient develops a tolerance to a first drug or to a first dose of the first drug, the impermeable membrane may be breached, to expose the underlying semipermeable membrane to the osmotic pressure of the patient at the implant site. This causes the infusion rate to increase, thereby providing the patient with the needed relief and / or other desired therapeutic effect. In the case of a multiple pump system, breaching an impermeable membrane may cause the infusion of a second drug. The second drug may potentiate a therapeutic effect (such as an analgesic effect) of the first drug, as is the case with Sufentanil and Clonidine.

Description

[0001] This application is related in subject matter to commonly assigned co-pending patent application Ser. No. 09 / 442,128 filed on Nov. 16, 1999 entitled "Methods And Implantable Devices And Systems For Long Term Delivery Of A Pharmaceutical Agent" (attorney docket MICR5591), the disclosure of which is hereby incorporated herein in its entirety.[0002] This application is also related in subject matter to commonly assigned co-pending patent application Ser. No. ______ filed on ______ and entitled "Osmotic Pump Delivery System With Pre-Hydrated Membranes(s) And / Or Primable Catheter" (attorney docket MICR5646), the disclosure of which is also hereby incorporated herein in its entirety.[0003] This application is also related in subject matter to commonly assigned co-pending patent application Ser. No. ______ filed on ______ and entitled "Osmotic Pump Delivery System With Flexible Drug Compartment" (attorney docket MICR5647), the disclosure of which is also hereby incorporated herein i...

AI Technical Summary

Benefits of technology

[0019] The present invention is also a drug delivery method, comprising the steps of infusing a first drug at a first therapeutically effective range of concentration from a first implanted osmotic pump; infusing a second drug at a second therapeutically effective range of concentration from a second implanted osmotic pump; preventing the first and second drugs from mixing until both the first and second drugs reach an intended delivery site.

Problems solved by technology

The actions of the digestive tract and the liver often reduce the efficacy of medication; furthermore, medications delivered systemically sometimes cause undesirable side effects.

Unfortunately, IV administration requires the use of a percutaneous catheter or needle to deliver the drug to the vein.

Infection is such a significant risk that IV administration is often limited to a number of weeks, at most.

Two problems associated with such 1970s and 1980s vintage constant rate and programmable rate infusion pumps relate to their size and their cost.

The current implantable pumps must be implanted in the Operating Room under general anesthesia, which further increases costs, as well as the risk, and discomfort to the patient.

The size and cost of such pumps has proven to be a substantial barrier to their use, and they are rarely used to deliver medication.

An added drawback of phase-change and peristaltic pumps is that they must be refilled with drug every 3-8 weeks.

Refills constitute an added burden to the caregiver, and add further costs to an already overburdened healthcare system.

The burden associated with such refills, therefore, further limits the use of phase-change and peristaltic pumps.

Should the patient develop a tolerance to the drug and require an increased dose to alleviate pain, for example, such a single drug / single dose pump is unable to provide the needed relief.

This, however, defeats the purpose of the implanted pump, namely to provide a self-contained drug delivery system that operates with little or no discomfort to the patient.

There may be instances, moreover, when a simple increased dose of the same drug is ineffective to achieve the desired therapeutic result.

Conventional osmotic pumps, however, are single drug or single drug combination devices: they can only infuse a single drug or a single combination of drugs at a time.

Images