Active delivery device with reduced passive delivery

• US 6,352,524 B1
• Filed: 12/09/1998
• Issued: 03/05/2002
• Est. Priority Date: 02/03/1997
• Status: Expired due to Fees

• Current Assignee: Interag
• Original Assignee: Interag
• Inventors: Rathbone, Michael John, Burggraaf, Shane, Bunt, Craig Robert
• Primary Examiner(s): Lewis, Kim M.
• Application Number:
  US09/207,514
• Time in Patent Office: 1,182 Days
• Field of Search: 606/119, 604/514, 604/515, 604/518, 604/93.01, 604/132, 604/140-148, 128/831, 128/832
• US Class Current: 604/285
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50

Abstract

A delivery device having a reservoir of variable volume having an outlet through which an included vehicle can be expressed in a liquid form as the volume of the reservoir is actively reduced. There is a tube providing a conduit to the outlet from the reservoir of such length and cross-section as to favor active release over passive release which has the effect of enabling a more positive control of the dispensing of the vehicle. Such a device has diverse applications.

Claims

1. A delivery device having a reservoir of variable volume having an outlet through which an included vehicle can be expressed in liquid from as the volume of the reservoir is actively reduced and wherein there is a dip tube providing a conduit to the outlet from the reservoir of such length and crosssection as to favour active release over passive release.

2. The device of claim 1 wherein the dip tube is in part within a collapsible bladder.

3. The device of claim 1 wherein the dip tube is part of a cylinder to reduce the reservoir volume.

4. The device of claim 1 wherein said dip tube is a plastic tube of circular cross-section less than 1 mm in internal diameter.

5. The device of claim 1 wherein the dip tube is such that the passive vehicle release rate of the device is less than 50% of the initial volume of vehicle over any insertion period.

6. The device of claim 5 wherein said passive release rate is less than 20%.

7. The device of claim 1 wherein said outlet, at least prior to first use, is capped.

8. The device of claim 1 wherein said reservoir is reduced in volume continuously.

9. The device of claim 1 wherein said reservoir is reduced in volume intermittently.

10. The device of claim 1 wherein active reduction of the volume is under the action of either

i) a gas or gases generated by the application of a controlled or controllable electric current to a water containing matrix at least one of contained, carried by and associated with the device in such a way as generates free oxygen and free hydrogen, or

ii) a gas or gases generated by the electrolysis of water contained in a hydrogel, at least one of, contained and carried by the device.

11. The device of claim 10 wherein said vehicle is or contains progesterone.

12. The device of claim 11 which is an intra vaginal device and the rate of expression enabled, whilst in the vaginal tract of a target mammal, by the content of a bladder containing the vehicle, the outlet and the gas generating means is sufficient to first achieve a progesterone plasma level above 2 ng/mL and thereafter maintain a level of at least 2 ng/mL in the mammal for a period of at least 4 days.

13. The device of claim 12 wherein the vehicle content of the bladder is from 1 to 60 mL.

14. The device of claim 10 wherein said device includes a plurality of reservoirs of variable geometry each separately controlled insofar as the expression therefrom of its content is concerned.

15. The device of claim 10, wherein the free oxygen and free hydrogen generated is done in the absence of other gases.

16. The device of claim 10, wherein the hydrogel is negatively charged for enabling hydrolysis of the water.

17. The device of claim 1 wherein the active reduction is under the action of gas (es) generated by at least one of a timer and a microprocessor control of a supply of an electrolysing electric current to a hydrogel.

18. The device of claim 17 wherein the source of electric current is from a battery contained by, carried or associated with the device.

19. The device of claim 17 wherein there is sufficient hydrogel to enable an active delivery of greater than 80% of the initial vehicle volume in a recommended insertion period.

20. The device of claim 19 wherein the recommended insertion period is at least 4 days.

21. The device of claim 11 wherein said device has a removable seal or cap on said outlet and is at least one of (i) capable of being removed prior to intra vaginal insertion, (ii) dissolves in the vaginal tract after insertion and (iii) is rupturable under the pressure of the vehicle to be released after sufficient gas has been generated by said gas generating means after a switch energizes a circuit.

22. A delivery device capable of expressing a liquid vehicle from an outlet of a reservoir, said device having at least one of a timer and a microprocessor, a power source and circuitry, electrodes and electrolyte matrix to be able to generate a gas from the electrolyte matrix so as to reduce the volume of the reservoir to cause active expression of the vehicle therefrom, there being a dip tube providing a conduit to the outlet from the reservoir of such length and crosssection as to favour active release of the vehicle from the reservoir over passive release of the vehicle from the reservoir.

23. The device of claim 22 wherein the conduct by capillary or other resistance to passive flow of the vehicles from the reservoir is such as to reduce any passive eggress of the vehicle.

24. A delivery device capable of expressing a liquid vehicle from the outlet of a reservoir, said device having at least one of a timer and a microprocessor, a power source and circuitry, electrodes and electrolyte matrix to be able to generate a gas from the electrolyte matrix so as to reduce the volume of the reservoir to cause active expression of the vehicle therefrom, there being a dip tube providing a conduit to the outlet.

25. A delivery device having a body, wherein said body has

a chamber having an outlet,

a bladder within said chamber sealed about said outlet to said body so as to be capable of delivering its contents via said outlet upon the application of gas pressure external of said bladder to the bladder, said bladder containing at least 1 mL of progesterone in a liquid delivery form, a dip tube providing a conduit to the outlet from within the bladder to affect the passive leakage rate of the delivery device, and

controlled or controllable gas generating means to generate a gas within said body so as to apply gas pressure within said chamber to the exterior of said bladder,

and wherein the gas generating means include

a hydrogel having electrolysis electrodes,

a batter powered circuit capable of applying a controlled or set current to said electrolysis electrodes so as to generate gas from the hydrogel which will have a pressurising effect on the exterior of said bladder,

switch means to allow energising of the circuit.

26. The device of claim 25 which is an intra vaginal device having an elongate body structure coupled to or having resilient means of variable geometry to facilitate in a target mammal vaginal tract insertion, to facilitate vaginal tract retention and to allow vaginal tract withdrawal, when the elongate axis of said body structure is substantially aligned to an axis of the vaginal tract.

27. The device of claim 25 wherein the rate of expression enabled, whilst in the vaginal tract of the target mammal, by the content of the bladder, the outlet and the gas generating means is sufficient to first achieve a progesterone plasma level above 2 ng/mL and thereafter maintain a level of at least 2 ng/mL in the mammal for a period of at least 4 days.

28. The device of claim 25 wherein said dip tub is a plastic tube of circular crosssection less than 1 mm in internal diameter.