FI97683C - Device intended for insertion of an intrauterine ring - Google Patents

Description

97683

INTRA-URBAN RING DEVICE DEVICE -ANORDNING AVSEDD FOR INSETTING AV EN INTRA-UTERIN RING

The invention relates to an applicator suitable for inserting a ring made of flexible polymeric material for use inside the uterus. Said ring contains an active substance such as a hormone.

A commonly used intrauterine device is a T-shaped body made of plastic surrounded by a partially wound copper wire capable of releasing copper-10 ions. The device is inserted into the uterus with a separate applicator. A wire is attached to the device that is so long that it extends out of the cervix when the device is inserted.

Various non-ring-15 intrauterine hormone donating devices are also known in the literature.

US 3656483 describes a hormone-donating IU (intra-uterine) device with laterally extending wings in place.

U.S. Pat. No. 4,014,988 describes hormone-releasing IU devices in which the active ingredient is dissolved in a liquid carrier in a container. The layer surrounding the container is a suitable polymer. IU devices are not annular but T-, 7-, or S-shaped.

U.S. Patents 4,264,575 to 4,246,578 all relate to IU devices in which the active ingredient is dispersed in a silicone polymer.

• · · · ;;; No device structures are disclosed in these patents, * · * ', but in the body of the patents reference was made to devices disclosed in earlier U.S. patents. None of these reference patents 30 relates to a unitary ring, but to a completely different type of structure.

U.S. Pat. No. 2,978,683, U.S. Pat.

U.S. Pat. No. 4,180,064 also relates to an intrauterine device, for example an octagonal device, in which the active ingredient is dispersed in a biodegradable polymer.

U.S. Pat. No. 4,871,543 and U.S. Pat. However, these rings are intended for vaginal insertion, and there is no mention or indication in the patents that the described rings are also suitable for uterine insertion.

T-shaped and other non-ring-shaped devices with sharp parts can cause pain to the wearer and even damage to the uterine wall.

The devices described in U.S. Patents 3,896,819 and 4,180,064 are of no practical significance. The system of U.S. Pat. No. 3,896,819 involves great risks: if the container in which the active ingredient is dissolved breaks, then the entire amount of drug is released simultaneously and causes a state of poisoning to the user. In order for such a container to remain intact during the placement of the device 25, it will be appreciated that its shape must be quite inflexible. This would easily cause damage to the cervix during insertion and removal of the device. A ring based on a biodegradable polymer described in U.S. Pat. No. 4,180,064 could not be considered in practice.

30 Biodegradable polymers are hard and inelastic, so it would be very difficult to fit rings made of such a material. Breaking the annular structure of the device during the decomposition process would make it very difficult to remove the device because the device is

ItL »mu Ι: Ι4β:. · 3 97683 lost shape and hard, broken parts would cause tissue damage.

The ring now developed is an intrauterine drug delivery ring, which may be either closed or open and to which a pull-out wire is attached. The ring is made of an elastic polymer material mixed with the active ingredient. Said ring may, if desired, be coated with a separate polymeric film controlling the release rate of the active substance. The polymer film may be made of the same or a different polymer or polymer blend than the active ingredient-containing polymer matrix. It is essential that the polymer used in both the matrix and the film be very flexible, and for this reason silicone polymers are particularly suitable. In principle, any active ingredient can be dispensed with the ring. However, the device is specifically designed for hormone delivery in the treatment of menopausal ailments or contraception. The hormones in question are estrogens and progestins.

20 The ring can be either closed or slightly open. For example, applying the method of fabrication described in U.S. Patent 4,888,074, open rings are obtained by cutting a twist. second extrudate in the direction of the coil axis. Individual: open rings can be closed if desired, but alternatively they can be used as is. For example, a ring may be circular, oval, elliptical, or otherwise curved. For example, the cross-section of the ring may be circular, oval, elliptical or otherwise suitably shaped.

30 The circular cross-section has the disadvantage that the rate of delivery of the active substance decreases over time due to the fact that the diffusion distance of the substance in the middle of the circle is considerably longer than near the circumference. ·. diffusion distance of the substance. In order to obtain the smoothest possible uniform rate of delivery of the active substance, the cross-section can be designed so that the travel of the active substance to the circumference 4 97683 at different points of the cross-section is substantially the same length. A preferred cross-sectional shape is a star, for example a four-pointed star with slightly rounded tips to avoid tissue damage. The cross-sectional shape is important only mainly in rings in which the active substance-containing polymer matrix is not coated with a separate film. If, on the other hand, a separate polymer film is used, this controls the rate of release of the active substance.

10

Most preferably, the ring has an outer diameter of about 18 mm and a tire cross-section of about 1.5 mm in diameter.

The extra high flexibility of the ring makes it easy to place even on menopausal women with a narrow uterine neck. The applicator can also be made very small.

The invention relates to an applicator for inserting the ring described above into the uterus. The features of the invention appear from claim 1.

The invention is described in more detail in the following figures, in which

Figure 1 shows the IU ring inserted into the uterus

Figure 2 shows an applicator according to the invention suitable for inserting a ring

Fig. 3 shows another embodiment of an applicator 25 suitable for inserting a ring · »* • · ·

Figures 4-7 show the setting of the ring. Figure 8 shows a cross-section of a ring of an embodiment:

Attached to the ring 12 is an pull-out thread 11 surrounding the sheath of the ring 12 · · H ». After insertion, the ends of the threads may be shortened somewhat, but it is recommended to leave them so long that they extend well out of the cervix even when the ring is inserted into the uterus 10. In this case, the ring can be removed.

Figure 2 shows an applicator 10 suitable for inserting a ring, the elongate body 15 of which consists of a tube through which a channel 16 passes. The handle 17 of the applicator forms an integral part with the body 15. The handle 17 is also provided with a through channel 16 ', which is suitably an extension of the channel 16. The end 18 of the body 15 is shaped so that the ring 12 resting on it remains well in place when the wire ends 11 'and 11' 'are tightened and locked in place by a locking member 19, which is shown only schematically in this figure. A ring 12 having a circular cross-section 22 in the example shown here is shown cut away. The channels 16 and 16 'may be holes passing through the bodies 15, 17 or grooves made in these bodies.

Figure 3 shows another embodiment of the applicator in which. the body 15 consists of a rod. The end 18 of the rod entering the uterus of the rod is shaped to support the ring 12. The end 18 has: a channel 20, which may be a hole or a groove, preferably for the passage of the pull-out wire. The tightening and locking of the wire ends 11 'and 11' 'is done in the same way as in the solution shown in Fig. 2. Alternatively, 30 rings can be placed at the end of the rod so that the wire attachment point • · · !!! will be located at 18 opposite ends of the head. Tire. is brought to this position by turning the ring shown in Fig. 3 180 °. By pulling the thread, you can already before inserting the applicator: and the ring fitted to it into the cervix. . ·. 35 biases the ring and makes it substantially rectangular as shown in FIG.

6 97683

Figures 4-7 show the insertion of the ring 12 into the uterus. The wire ends 11 'and 11' 'are tightened and locked by means of a locking member 19, whereby the ring rests against the end 18 of the applicator. The applicator is inserted through the cervix until the stop 21 located in the body of the inserter between the handle 17 and the end 18 of the body indicates that the ring is at the top of the uterus. The tension of the wire ends 11 'and 11' 'is removed by releasing the wire ends from the locking member. The applicator is pulled out and the ring remains in the uterus. It can be seen from Figures 5 and 7 that the ring 10 is very flexible. Due to the low compression pressure or low traction, the circumference of the ring can be formed into a substantially rectangle, the long sides 12 'and 12' 'of which run very close to each other. Figure 4 shows the insertion of the tire without prestressing. Figure 7 15 shows the insertion of a prestressed ring.

Figure 8 shows a preferred shape of the cross-section 22, i.e. a four-pointed star with slightly rounded tips to avoid tissue damage.

The polymers and active ingredients used in the ring described above are components commonly used in vaginal rings. The passage of the active substance in the polymer matrix and its release rate through the polymer film follow the same patterns as in the known vaginal rings described in e.g. U.S. Patent 4,871,543.

It will be apparent to one skilled in the art that various embodiments of the invention may vary within the scope of the claims set forth below.

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Claims (2)

97683 PAT CLAIM ET