WO2009081097A1

WO2009081097A1 - Applicator for pessary

Info

Publication number: WO2009081097A1
Application number: PCT/GB2008/004118
Authority: WO
Inventors: Janet Anne Halliday; Alistair Chassels Ross
Original assignee: Controlled Therapeutics Scotland Ltd
Current assignee: Controlled Therapeutics Scotland Ltd
Priority date: 2007-12-24
Filing date: 2008-12-12
Publication date: 2009-07-02
Anticipated expiration: 2010-06-24

Abstract

An applicator for insertion of a pessary into a body cavity comprises a body (10) and a plunger (12). The body has a hollow head portion (14) accommodating the pessary and a handle portion (16). A slot (26) allows the pessary and its elongate retrieval tape (24) to be introduced into the hollow head. The pessary is ejected by the plunger and the tape passes through the slot.

Description

APPLICATOR FOR PESSARY

The present invention relates to an applicator for introducing a pessary into a body cavity of a patient, particularly for introducing a vaginal pessary.

Pessaries are well known for use against vaginal infections, particularly fungal or bacterial infections. The pessary is typically formed of a material which releases the active agent over an extended period of time. For example, pessaries may be formed of polyurethane hydrogels of the type disclosed in patent specifications GB2047093 and GB2047094. A typical pessary is flat with rounded ends of a suitable size for insertion into the vagina, usually between 30mm x 10mm x 0.8mm and 45mm x 15mm x 1.5mm, but preferably 30mm in length, 10mm wide and 1.5mm thick. In order to allow the spent pessary to be removed once release of the active agent has taken place, it is conventional to provide the pessary with a retrieval system, which may include a tape which allows the pessary to be withdrawn. European patent 0577891 discloses an integrally knitted retrieval system which comprises a pouch for containing the solid pessary and an elongated tape portion which allows the pessary to be withdrawn. The pouch includes a slit, which allows the pessary to be introduced during assembly. Although it is possible to insert pessaries into the vagina by hand, this is a crude method and has hygiene issues associated with its use, particularly with patients suffering from vaginal infections. Furthermore this method of insertion does not guarantee the pessary will be positioned at the right location in the vagina and with the right orientation. Therefore, it is essential that the pessary be introduced head-first (i.e. the leading end of the retrieval tape containing the pessary is introduced first), to enable the spent pessary to be smoothly withdrawn.

There is therefore a need for an applicator which is of sufficient length to position the pessary (having a retrieval system) in the correct location within the vagina. It is also important that the pessary be introduced with the correct orientation.

Applicators for tampons are well known in the art but the available designs have proved incapable of delivering pessaries having a retrieval system, as described above. A typical tampon applicator comprises a hollow outer tube having retaining petals at one end and a hollow cylindrical plunger slideable within the outer tube. The tampon is located within one end of the outer tube and is retained by the petals. The tampon has a retrieval cord which passes through the hollow plunger. To insert the tampon, the device is inserted into the vagina and the plunger is operated to expel the tampon through the petals. Once it has been expelled, the applicator may be removed leaving the retrieval cord in place. Such applicators have proved unsuitable for pessaries, since the net of the retrieval system can snag on the petals or cannot be threaded through the plunger. Moreover, the cylindrical shape of the applicator is unsuitable for comfortably retaining the flat pessary.

A further problem with these tampon applicators is that threading of the retrieval cord down a hollow applicator is problematical. The net tape retrieval system is generally made on a continuous roll, so that the applicator design must be able to accommodate this during the production process.

US 3,918,452 discloses a tampon applicator, where the retrieval cord is accommodated in a longitudinal slot extending to the open end of the applicator.

German patent specification OS 1766697, discloses an applicator for a pessary. The pessary in compressed form is introduced through a slot 62. A plunger is then operated to eject the compressed pessary out of ring 61. However, this arrangement does not disclose a construction suitable for use with a retrieval cord. US patent 4,742,820 discloses an applicator for introducing a circular diaphragm into the vagina.

Other known applicators include those for the administration of vaginal tablets, which feature an oval cup from which the tablet is expelled using a plunger. However, the cup shape does not allow for the correct positioning of the retrieval tape. If the pessary is inserted into the cup free-end first, then the pessary is inserted into the patient with the wrong orientation and has to do a somersault when it is withdrawn. Inserting the pessary into the cup with the other trailing end first means that the retrieval tape has to lie alongside the pessary in the cup; and the pessary can be easily dislodged by accident.

The present invention provides an applicator accommodating a pessary, the applicator being for insertion of the pessary into a body cavity, and comprising a body at a leading end of the applicator and a plunger slideable within the body; the body comprising a hollow head portion at a leading end thereof, the head portion being sized to slideably accommodate the pessary; and a handle portion attached to the head portion; and a slot at an end of the head portion adjacent the handle portion and sized to allow the pessary to be introduced into the hollow in the head portion therethrough; and the handle portion having a hollow core leading into the hollow head portion, and the plunger being slideably accommodated within the hollow core; and slideable such as to eject the pessary from a mouth of the hollow head portion; and the pessary having an elongate retrieval system passing out through the slot in the head portion. Thus, the inclusion of a slot in the head portion allows the pessary and elongate retrieval system to be introduced into the head portion in the same direction as the pessary will be ejected into the patient. The elongate retrieval system (e.g. a tape or string) is able to pass through the slot and follows the pessary.

Generally, the hollow head portion of the body will be rectangular in cross - section to match the cross-section of the pessary, thereby slideably retaining the pessary in place. This prevents the pessary from becoming prematurely ejected by accident. In use, the applicator body is introduced into the vagina to the correct depth, which may be determined by providing a stop at the trailing end of the applicator body. The plunger is then slid forward to push the pessary within its net retrieval system out of the hollow head portion of the body and into the vagina. At this point, the retrieval system is still partially retained in the head portion of the applicator and passes out of the slot; but the majority of it is outside the body and lies alongside the length of the body. Once the pessary has been ejected, the applicator may be withdrawn. As the applicator is withdrawn, the slot slides along the length of the retrieval system until it is free.

The pessary is provided with an elongate retrieval system, which allows the spent pessary to be withdrawn from the patient in a simple manner. The retrieval system may comprise a tape, string, cord etc. attached directly or indirectly to the pessary itself. It is preferred to enclose the pessary within an integrally formed retrieval tape having a pouch containing the pessary and an elongate retrieval tape portion. The tape can be formed of a knitted or woven net material, which accommodates any swelling of the pessary. The pouch usually includes a slit, through which the pessary is introduced during assembly. The pessary itself is usually formed of a cross-linked water-swellable polyurethane hydrogel, formed by the reaction of a polyethylene glycol, a polyol and a diisocyanate. It is generally loaded with a pharmaceutically active agent.

Generally, the applicator is intended for single use and is disposable. Alternatively, the applicator could be reused, since it is relatively easy for the patient to introduce the pessary and retrieval system through the slot in the hollow head portion with the correct orientation.

Generally, the slot has a bevelled lead-in portion on the side remote from the free leading end of the body, which facilitates introduction of the pessary into the hollow head portion. The pessary may be somewhat flexible, which means that it may bend slightly as it is introduced through the slot. Once the pessary is completely within the hollow head portion, it clicks into place and rests at the bottom end of the applicator head, preventing the pessary from sliding out of the slot again. However, the applicator is also able to deliver rigid pessaries.

Generally, the applicator is formed of a smooth flexible plastics material which allows some bending as it is introduced into the vagina and is therefore comfortable to use. The applicator has rounded contours to prevent irritation and abrasion and to facilitate insertion. The applicator is generally made by injection moulding.

The plunger may be of any suitable cross-section but is usually flat and of a width which matches the internal dimension of the hollow head portion so as to be slideable therein; and the hollow core of the handle portion also has a complimentary cross-section. In order to prevent the plunger from accidentally falling out of the applicator, the plunger preferably has an enlarged cross-section at its leading end, for example, in the form of one or more nibs, or flanges on the body of the plunger, which are wider than the hollow core but narrower than the hollow head portion. During assembly, the natural resiliency of the material allows the nibs to become compressed as the plunger is slid up the hollow core and then to become engaged within the hollow head portion. Preferably, there is a stop at the trailing end of the plunger to prevent the plunger falling out of the leading end of the applicator.

In another embodiment, the slot has a cut-away portion which extends to the free end of the body and facilitates passage of the applicator over the retrieval system during removal of the applicator from the vagina.

The invention also relates to a method of assembling the applicator, including the pessary and its retrieval system; and also to a method of using the applicator to introduce a pessary into the vagina or other body cavity. For example, the applicator may also be used rectally.

The applicator is typically assembled and loaded in the following manner. First, the plunger is inserted into the hollow core through the trailing end of the handle portion until the leading end of the plunger stops short of the slot. Then, the pessary within its elongate retrieval system is slid into the slot, pessary first. Once the rear end of the pessary passes through the slot it becomes engaged in the rear end of the hollow head portion with the retrieval tape passing out through the slot. In use, the leading end of the applicator is inserted into the vagina, typically about 20 cm inside so as to position the pessary correctly. The plunger is then pushed in so as to eject the pessary from the leading end of the applicator. The retrieval tape passes through the clearance between the inside of the hollow head and the plunger. The clearance is, however, not so large as to allow the plunger to ride over the pessary. The pessary is then gripped by the tissues within the vagina, which holds it in place as the applicator is withdrawn. As the applicator is withdrawn, the retrieval system (e.g. the tape) passes through the slot until the applicator is free. When the pessary has been in place for the required length of time (typically 1 or 2 days) the spent pessary may be removed from the vagina by pulling on the retrieval tape.

Embodiments of the present invention will now be described by way of example only in the following drawings, wherein:

Figure 1 is a top view of an applicator according to the invention showing a partly-ejected pessary and retrieval tape;

Figure 2 is a cross-sectional view; and

Figure 3 is a partial view of a further embodiment wherein the slot is elongated.

The applicator shown in Figures 1 and 2 comprises a body 10 and a slideable plunger 12.

The body 10 comprises a hollow head portion 14 and a handle portion 16. The hollow head portion has an open leading end 18 and is rectangular in cross-section to accommodate a pessary 20 contained within a woven net tape retrieval system 22 having a retrieval tape 24. The hollow head portion also includes a slot 26 having a bevelled trailing edge 28 which allows the pessary to be introduced through the slot and to be retained within the hollow head portion with the retrieval tape 24 passing out through the slot.

The handle portion includes a hollow core 30 which slideably accommodates the stem 32 of the plunger. The plunger has nibs 34 at either side of the leading end of the plunger to retain the plunger in place and prevent it accidentally sliding out. The trailing end of the plunger includes a flattened stop portion 36 which facilitates the plunger being pushed with the fingers or thumb. There is a corresponding stop portion 38 on the end of the handle portion of the body which allows the applicator to be pushed into the vagina during insertion and before operation of the plunger. The stem of the plunger is of constant rectangular cross-section.

During assembly, the leading end of the plunger is slid into the hollow core of the handle portion until the leading end of the plunger stem enters the hollow head portion and the nibs retain the plunger in place. For the sake of clarity, the leading end of the plunger is shown within the slot. However, it is withdrawn to the rear of the slot before the pessary in its net retrieval system is introduced through the slot and into the hollow head portion. In the drawing, the free end of the pessary within the retrieval system is shown partly ejected from the leading end of the applicator.

Figure 3 shows a further embodiment wherein the slot 26 includes a cut-away portion 40 leading from the slot to the free end of the hollow head portion and which facilitates removal of the applicator from the retrieval cord after insertion of the pessary into the vagina.

Claims

CLAIM

1. An applicator accommodating a pessary, the applicator being for insertion of the pessary into a body cavity, and comprising a body at a leading end of the applicator and a plunger slideable within the body; the body comprising a hollow head portion at a leading end thereof, the head portion being sized to slideably accommodate the pessary; and a handle portion attached to the head portion; and a slot at an end of the head portion adjacent the handle portion and sized to allow the pessary to be introduced into the hollow in the head portion therethrough; and the handle portion having a hollow core leading into the hollow head portion, and the plunger being slideably accommodated within the hollow core; and slideable such as to eject the pessary from a mouth of the hollow head portion; and the pessary having an elongate retrieval system passing out through the slot in the head portion.

2. An applicator according to claim 1, wherein the hollow head portion of the body is rectangular in cross-section to match the cross-section of the pessary.

3. An applicator according to claim 1 or 2, which further comprises a stop at the trailing end of the body which enables the applicator to be introduced into the vagina to the correct depth.

4. An applicator according to any preceding claim, wherein the slot has a bevelled lead-in portion on a side remote from the free leading end of the body.

5. An applicator according to any preceding claim, wherein the plunger has an enlarged cross-section at its leading end to prevent it falling out of the trailing end of the applicator.

6. An applicator according to any preceding claim, wherein the plunger has a stop at a trailing end thereof to prevent the plunger falling out of the leading end of the applicator.

7. An applicator according to any preceding claim, wherein the slot has a cutaway portion which extends to the free end of the body.

8. An applicator according to any preceding claim, wherein the elongate retrieval system comprises an integrally formed retrieval tape having a pouch for containing the pessary and an elongate tape portion.

9. An applicator according to claim 8, wherein the elongate retrieval system is formed of a net material.