WO2023199021A1

WO2023199021A1 - Infusion devices and components thereof

Info

Publication number: WO2023199021A1
Application number: PCT/GB2023/050820
Authority: WO
Inventors: Lisa JAUNET VAN KOOTEN; Jesper Erichsen
Original assignee: Convatec Limited
Priority date: 2022-04-11
Filing date: 2023-03-29
Publication date: 2023-10-19
Also published as: GB202205294D0

Abstract

A device for fixing an infusion device to a skin surface of a patient, and an infusion device for subcutaneous infusion of a therapeutic agent comprising the device, the device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to said skin surface of said patient; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

Description

INFUSION DEVICES AND COMPONENTS THEREOF

TECHNICAL FIELD

The invention relates to infusion devices and components thereof. Particularly, though not exclusively, the invention relates to a device for fixing an infusion device to a skin surface of a patient. Such infusion devices are for infusing a therapeutic agent, for example insulin, to patients, for example those living with diabetes.

BACKGROUND

For patients with diabetes, insulin therapy is often an important part of their treatment, helping to regulate blood sugar levels and store excess glucose for energy. One mode of delivering insulin is an infusion pump, sometimes called an insulin pump, which delivers controlled doses of insulin throughout the day. An infusion pump can be used to deliver insulin to a patient continuously (basal dose), on demand (bolus dose) or at scheduled intervals. This mode is known as continuous subcutaneous insulin infusion (CSII) therapy.

Infusion pump systems for CSII therapy may be worn by the patient. The systems typically include a combined infusion pump and reservoir for containing an insulin drug, for example human insulin or analogue insulin, and an insulin infusion set. The infusion set may include a cannula (for example, a polymeric catheter or metal needle) for insertion subcutaneously into the patient and flexible tubing for fluidly connecting the cannula to the reservoir. Once the cannula is inserted into the patient, it may remain in place for a period of time, i.e. days, to allow for continuous delivery of the insulin drug.

The infusion set will also include a plaster component (an adhesive patch), which in simple form may be an adhesive layer for fixating the infusion set to the patient’s skin. The plaster component will include an adhesive, for example Pressure-Sensitive Adhesive (PSA) or Silicone Soft-skin Adhesive (SSA), as described in US2009/0012473, an acrylic adhesive, urethane-based adhesive or hydrocolloid adhesive. A backing layer or cover film may be used to temporarily cover a face of the plaster component prior to use. While problems relating to the infusion set have been well investigated and addressed in recent years, there remains little understading and few solutions to address problems relating to teh infusion site. Problems relating to the infusion site include pain, bleeding, infection, skin irritation, fibrosis, erythema, lipohypertrophy and lipoatrophy.

WO2021/119360 discloses an infusion site treatment device aiming to reduce scars.

Lipohypertrophy is a local accumulation of fatty tissue at the site of injection/infusion. It is believed that the fat cells (adipocytes) may be stimulated to grow and proliferate due to the insulin, resulting in bumps in the skin. This can result in the skin area being unsuitable for further infusion, due to physical reasons or due to reduced insulin uptake. This also affects patients from a cosmetic perspective. These problems can deter or prevent patients from continuing to use their infusion pumps, resulting in poorer patient outcomes.

It is an object of embodiments of the invention to provide an improved device and/or at least mitigate one or more problems associated with known arrangements.

SUMMARY OF THE INVENTION

According to an aspect of the invention, there is provided a device for fixing an infusion device to a skin surface of a patient, the device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to said skin surface of said patient; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

The device may comprise an inlet extending through the plaster component for a fluid pathway to pass therethrough.

According to another aspect of the invention, there is provided a device for fixing an infusion device to a skin surface of a patient, the device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to said skin surface of said patient; an inlet extending through the plaster component for a fluid pathway to pass therethrough; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

According to another aspect of the invention, there is provided an infusion device for subcutaneous infusion of a therapeutic agent, the infusion device comprising: a hub part, a fixing device to fasten the hub part onto a patient's skin, and a cannula or needle extending through the fixing device, the fixing device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to a skin surface; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

The infusion device may comprise an inlet extending through the plaster component for a fluid pathway to pass therethrough.

According to another aspect of the invention there is provided an infusion device for subcutaneous infusion of a therapeutic agent, the infusion device comprising: a hub part, a fixing device to fasten the hub part onto a patient' s skin, and a cannula or needle extending through the fixing device, the fixing device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to the skin surface; an inlet extending through the plaster component for the cannula or needle to pass therethrough; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

With these arrangements, there is provided an improved connection between an infusion hub and the patient, and thereby an improved infusion device is provided. In particular, the device is able to apply a compressive force to the skin area in the region of the injection site while the infusion device is in use. Such a compressive force will help to combat the above-mentioned problems associated with stimulation of fat cells.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying figures, in which:

Figure 1 is a perspective view of an upper side of a device;

Figure 2 is a top view of the device of Figure 1 ;

Figure 3 is a bottom view of the device of Figure 1 ;

Figure 4 is a perspective view of a lower side of the device of Figure 1 ;

Figure 5 is a side view of the device of Figure 1 ;

Figure 6 is a side view of the device of Figure 1 in an inflated position;

Figure 7 is a side view of another device being positioned on the skin surface;

Figure 8 is another side view of the device of Figure 7 in position;

Figure 9 is a perspective view of the underside of the device of Figures 7;

Figure 10 is a perspective view of the underside of another device;

Figure 11 is a side view of the device of Figure 10;

Figure 12 is a cross sectional view of an infusion set; and

Figure 13 is a schematic view of an infusion device.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the invention have particular application for use with infusion pump systems such as an infusion pump for delivery of a therapeutic agent, the infusion pump comprising a fluid pump and a reservoir, and an infusion set having a cannula and tubing for connecting the cannula to the reservoir. However, other applications are contemplated, for example catheter access ports and alternative infusion pump systems such as patch pumps, which have no tubing. Embodiments of the invention may be used in closed loop systems. In certain embodiments, the infusion pump may be an insulin pump for CSII therapy and the therapeutic agent may be an insulin drug, for example human insulin or analogue insulin. Embodiments of the invention are intended for delivering insulin to a patient at a single infusion site over an extended period of time.

Infusion devices and infusion sets will first be described with reference to Figures 12 and 13.

Figure 12 shows a device 110 having a base 112 that is securable to the skin at an infusion site 114, by an adhesive patch (known as a plaster) 116, to maintain a cannula 118 within the sub-dermal tissue of a patient. The base 112 further has a port 120 for receiving the cannula 118. The base 112 is configured for attachment to an infusion cap 122 for delivering a therapeutic agent to the cannula 118 and, subsequently, into the infusion site 114. The therapeutic agent may be insulin or an insulin solution.

Together, the base 112 and the cap 122 provide an infusion hub, which serves as a fluid connector between the cannula 118 and a length of tubing 124. To effect and maintain attachment of the cap 122 to the base 112, the base 112 may have a rim 126 extending about its periphery that is configured to engage a cooperating rim 128 extending about the periphery of the infusion cap 122. The base 112 may include a self-sealing septum 130 disposed in or over the port 120.

The cannula 118 is a substantially tubular member for insertion in, and delivering the therapeutic agent to, the infusion site 114. A proximal end 118a of the cannula 118 is fluidly connected to a source of the therapeutic agent, for example a reservoir in an infusion pump system, via the tubing 124. An opposing, distal end 118b of the cannula 118 is positioned in the infusion site 114, extending to a desired depth to deliver the therapeutic agent. As the skilled person will appreciate, each of the base 112, the cannula 118, the infusion cap, and the tubing 124, in part provide a fluid pathway between the source of the therapeutic agent and the infusion site 114.

The device 110 may also comprise an insertion needle, for example when the cannula 118 is a soft, polymeric catheter. To this end, the device 110 may be configured to be applied to the infusion site 114 using an inserter device. Inserter devices, which are sometimes called inserters or injectors, are used commonly in the medical field for inserting medical devices subcutaneously into a patient. Infusion sets, infusions hubs and inserter devices suitable for use in embodiments of the invention are known in the art, and examples are disclosed in earlier patent applications, including W02007/092210, WO2010/112521 , US755173, US5176662, US5257980 and WO98/9856693, the contents of which are incorporated herein by reference.

Figure 13 illustrates an infusion device 1100 including components of an infusion pump system. The device 1100 includes the device 110 described above with reference to Figure 12, including the base 112 and infusion cap 122, together forming the infusion hub, the cannula 118 and the tubing 124. The infusion hub, the cannula 118 and the tubing 124 together form an infusion set. The device 1100 further includes a combined infusion pump 1142 and reservoir 1144 for containing the therapeutic agent. A fluid pathway is provided from the reservoir 1144 to the infusion site 114, for conveying the therapeutic agent. The fluid pathway extends from the reservoir 1144 to the tubing 124, through the tubing 124, from the tubing 124 to infusion cap 122, through the infusion cap 122, from the infusion cap 122 to the base 112, through the base 112, from the base 112 to the cannula 118 and through the cannula 118.

As mentioned above, an adhesive patch (known as a plaster) 116 is used to secure a device 110 (or an infusion hub) to the skin at an infusion site 114. Figures 1-6 illustrate an example of a device 100 for fixing an infusion device (not shown) to a skin surface 10 of a patient. Such a device may be used in place of the above-mentioned adhesive patch 116 in an infusion set and in an infusion device. The device 100 includes a plaster component 2 including first and second side surfaces 4,6, said first side surface being provided with an adhesive portion 8 for fixing the plaster component relative to the skin surface 10 of a patient. The device also includes an inlet 12 extending through the plaster component for a fluid pathway to pass therethrough. The device further includes a pressurizing component 14 extending from the first side surface 4 of the plaster component.

The plaster component 2 is a generally planar element and includes a first side surface 4, being a surface that will meet and join to the patient’s skin surface 10 in use. The first side surface 4 has an adhesive portion 8 for fixing the plaster component 2 relative to said skin surface 10 of said patient. As best shown in Figures 3 and 4, the adhesive portion 8 covers substantially the full surface area of the first side surface. In particular, the adhesive portion 8 covers four areas 8a-d of the first side surface 4, to ensure a good adhesion to the skin. In this example, the four areas 8a-d are separated by channels 9a-d that extend from a central point C to the periphery.

As best shown in Figures 1 and 2, the plaster component 2 also includes a second side surface 6, generally opposing the first side surface 4. The second side surface 6 will, in use, adjoin to the base of an infusion hub (not shown). The second side surface may also include an adhesive portion to enable fixation to an infusion hub. The second side surface may also include channels, similarly to the first side surface.

The channels 9a-d on the ‘skin side’ of the plaster component, and the channels on the ‘hub side’ of the plaster component are optional, and are provided to help flexibility of the plaster component, and thereby movement of the inflatable cushion (described below).

The device 100 also includes an inlet passageway 12 extending through the plaster component 2. The inlet 12 is a hole or passageway passing through the plaster component 2 and is sized to allow a cannula to pass through. The inlet 12 is located at a central point C of the plaster component 2. The inlet passageway 12 allows a fluid pathway, e.g. a cannula, to pass therethrough from the infusion hub towards the patient.

The device 100 also includes a pressurizing component 14 extending from the first side surface 4 of the plaster component 2. The pressurising component in this example is an inflatable cushion including an annular wall 14a enclosing an inner space 14b. The cushion element 14 is configured to receive fluid into the inner space 14b. the cushion is an inflatable annular ring, having a central port 5 for enabling a fluid pathway, e.g. a cannula, to pass therethrough. The central port 5 aligns with the inlet 12 of the plaster component 2.

Figure 5 shows the pressurizing component 14 in a deflated state and Figure 6 shows the pressurizing component 14 in an inflated state. As can be seen in Figure 1 , the central port 5 includes an inlet port 3 for receiving fluid, e.g. air, into the inner space 14b of the inflatable cushion. The inlet port 3 may be connected to tubing and ultimately a fluid source, for control of fluid addition to (or removal from) the inflatable cushion. As such, addition of fluid into the cushion inflates the cushion to the larger size, as shown in Figure 6.

As shown in Figure 6, the expanded state of the cushion gives generally an increase in the depth direction of the cushion, i.e. the dimension perpendicular to the planar direction of the plaster and the skin surface. In use, in the expanded state, since the second side surface 6 of the plaster adjoins an infusion hub, the plaster is prevented from moving in the direction towards the infusion hub. Instead, the cushion is urged towards the skin surface. The pressurising component, and in particular the cushion, imparts compressive force onto the skin surface. The pressure applied to the skin is at least 225 Pa. The pressure applied may be tailored to the particular patient’s needs. The pressure may be at least 1 kPa, or 20kPa, or 100kPa, or 250kPa, or 500kPa. The cushion, and thereby the pressurizing component, is configured to impart a pressure over an area of at least 3 cm². The skin area directly adjacent the cushion will receive pressure from the cushion. It is also likely that adjacent areas of skin will receive some amount of pressure from the cushion.

In the arrangement described above, the inflatable cushion effectively provides a measurable minimum and maximum force component. This provides great certainty in relation to the quantifiable level of compressive pressure, and the area over which the pressure is applied, and thus the force provided to the patient’s skin.

It will be clear that a series of investigations are possible to determine the relationship between cushion dimensions, inflation level, and the resultant compressive force provided to the skin area. The user will be able to adjust the inflation level to the appropriate amount for a particular patient.

In use, the device 100 may be applied first to the skin of the patient. Then, an infusion set may be applied over the device 100. Alternatively, the device 100 may be connected with an infusion device, and the set be applied to the skin of the patient. The cushion may be inflated prior to application on the skin surface. However it is envisioned that the cushion is inflated after the device 100 and the infusion device are already in situ. The cushion may be inflated at a measured rate in order to pressurise the skin area slowly to avoid pain to the patient.

With the arrangement described above, an improved device is provided that enables infusion of a medicament to be performed while a compressive force is applied to the skin area of a patient. The compressive force may be useful in helping prevent or reduce disorders such as lipohypertrophy.

Figures 7-9 show another example of a device 200 for fixing an infusion device (not shown) to a skin surface 10 of a patient. The device 200 includes a plaster component 202 including first and second side surfaces 204,206. The first side surface is provided with an adhesive portion 208 for fixing the plaster component relative to the skin surface 10 of a patient. The adhesive portion covers the full surface of the first side of the device. The plaster component is generally similar to the plaster component of the above example of Figure 1. The device further includes a pressurizing component 214 extending from the first side surface 204 of the plaster component.

In this example, the device does not require a specifically constructed inlet through the plaster component and pressurizing component for a fluid pathway to pass therethrough. That is because, the material of the plaster component 202 and the pressurizing component 214 are of a material that is malleable to allow a needle or cannula to be pushed through them.

The pressurizing component 214 is a convex projection extending from the first side of the plaster component, of a silicone material. Alternatively the pressurizing component 214 could be of a plastic material or a foam material. In this case the convex projection is a dome shape, though other shapes can be foreseen, e.g. cylindrical, flat bottomed shapes.

Figure 8 shows the device 200 in situ on the patient’s skin. Figure 9 shows the underside of the device. The infusion set is not shown in these drawings, but will be present during application of the device 200 to the skin, or after application of the device to the skin. As can be seen in Figure 8, the pressurizing component imparts a compressive force to the area of skin that it contacts. The malleability of the pressurizing component will determine any amount of radially outward spread of the component as it is forced against the skin. This will of course determine the area over which the compressive force is applied.

The arrangement provides a particularly straight forward design with minimal parts for allowing a compressive pressure to be applied to a skin area during infusion of a medicament. Figures 10 and 11 show a device 300 similar to that of Figures 8 and 9. However, this device 300 includes an annular projection 314 as a pressurizing component. The annular projection extends from a first side 304 of a plaster component 302.

The annular projection may be of a silicone material, a plastic material, or a foam material for example.

The annular nature of the projection 314 allows for a compressive force to be applied to the patient’s skin during infusion of a medicament (in the same matter as described in the previous examples). However, the absence of material in the central area of the projection allows a needle or cannula to be passed through the projection. As such, a wider choice of (bio-compatible) materials are available for the material of the pressurizing component.

It will be understood that any of the above-described devices will be useable as a component of an infusion set and an infusion device.

An infusion device may include a hub part, a fixing device to fasten the hub part onto a patient' s skin, and a cannula or needle extending through the fixing device. The fixing device may be any of the devices 100, 200, 300 described above.

Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

Claims

1 . A device for fixing an infusion device to a skin surface of a patient, the device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to said skin surface of said patient; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

2. A device as claimed in claim 1 , comprising an inlet extending through the plaster component for a fluid pathway to pass therethrough.

3. A device as claimed in claim 1 or 2, wherein the pressurizing component is configured to impart a compressive force over an area of at least 3 cm².

4. A device as claimed in any preceding claim, wherein the pressurizing component is configured to impart a compressive force of at least 1kPa, or 20kPa, or 100kPa, or 250kPa, or 500kPa.

5. A device as claimed in any preceding claim, wherein the pressurizing component is a convex projection extending from the first side surface, comprising a silicone material, a plastic material, or a foam material.

6. A device as claimed in any preceding claim, wherein the pressurizing component is an annular projection extending from the first side surface, comprising a silicone material, a plastic material, or a foam material.

7. A device as claimed in any preceding claim, wherein the pressurizing component is an inflatable cushion element comprising an annular wall enclosing an inner space, the cushion element configured for receiving fluid into the inner space.

8. A device as claimed in claim 7, wherein the cushion element includes a central port for a fluid pathway to pass therethrough.

9. A device as claimed in claim 7 or 8, wherein the cushion element includes an inlet port for receiving fluid into the inner space.

10. An infusion device for subcutaneous infusion of a therapeutic agent, the infusion device comprising: a hub part, a fixing device to fasten the hub part onto a patient's skin, and a cannula or needle extending through the fixing device, the fixing device comprising: a plaster component including first and second side surfaces, said first side surface being provided with an adhesive portion for fixing said plaster component relative to a skin surface; and a pressurizing component extending from the first side surface of the plaster component, for imparting compressive force onto the skin surface of at least 225 Pa.

11. An infusion device as claimed in claim 10, comprising an inlet extending through the plaster component for a fluid pathway to pass therethrough.

12. An infusion device as claimed in claim 10 or 11 , wherein the pressurizing component is configured to impart a compressive force over an area of at least 3 cm².

13. An infusion device as claimed in any of claims 10 to 12, wherein the pressurizing component is configured to impart a compressive force of at least 1 kPa, or 20kPa, or 100kPa, or 250kPa, or 500kPa.

14. An infusion device as claimed in any of claims 10 to 13, wherein the pressurizing component is a convex projection extending from the first side surface, comprising a silicone material, a plastic material, or a foam material.

15. An infusion device as claimed in any of claims 10 to 14, wherein the pressurizing component is an annular projection extending from the first side surface, comprising a silicone material, a plastic material, or a foam material.

16. An infusion device as claimed in any of claims 10 to 15, wherein the pressurizing component is an inflatable cushion element comprising an annular wall enclosing an inner space, the cushion element configured for receiving fluid into the inner space.

17. An infusion device as claimed in claim 16, wherein the cushion element includes a central port for a fluid pathway to pass therethrough.

18. An infusion device as claimed in claim 16 or 17, wherein the cushion element includes an inlet port for receiving fluid into the inner space.

19. An infusion device as claimed in any of claims 10 to 18, wherein the device is a portable insulin pump.

20. An infusion device as claimed in any of claims 10 to 18, wherein the device is an infusion set for subcutaneous infusion of insulin.