GB2626198A

GB2626198A - Catheters

Info

Publication number: GB2626198A
Application number: GB2301916.9A
Authority: GB
Inventors: Pollard David; Metcalf Daniel; Allen Daniel; Meredith Kate
Original assignee: Convatec Ltd
Current assignee: Convatec Ltd
Priority date: 2023-01-12
Filing date: 2023-02-10
Publication date: 2024-07-17
Also published as: GB202301916D0

Abstract

The invention provides a reusable urinary catheter kit comprising a container comprising: a urinary catheter; and a medium comprising at least one species independently chosen from: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof at a concentration of 0.005 – 0.6 wt% of the medium. The invention further provides a method of sterilising and/or lubricating a reusable urinary catheter using at least one species independently chosen from: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof. Sodium hydroxide or sodium chloride may also be present in then medium which is preferably an aqueous solution. In an embodiment, sterilisation takes place by immersing the catheter in the sterilising medium. In an embodiment, the sterilising medium is provided in a separate container, so it is not in contact with the catheter. The secondary container is punctured when the medium is required. Amphiphilic compounds, including block-copolymers, may also be included in the sterilising medium.

Description

CATHETERS

Technical Field of the Invention

The present invention relates to reusable urinary catheters and to sterilising media comprising chlorine-based species for reusable urinary catheters.

Background to the Invention

Urinary catheterisation is a process involving insertion of a catheter through an individual's urethra and into their bladder, where it is retained to empty the bladder of urine. There are two major types of urinary catheterisation -intermittent catheterisation and long-term catheterisation. Intermittent urinary catheterisation involves retaining the catheter in the bladder for only the time period required for emptying, after which the catheter is removed. The process differs from long-term catheterisation, which makes use of an indwelling or Foley catheter that is inserted into the bladder for long periods of time (several days to months) to discharge the residual urine of the bladder continuously throughout the day.

Catheterisation is often used by patients suffering from abnormalities of the urinary system, resulting in urinary incontinence and/or a lack of control in permitting voluntary urination. Such individuals would typically make use of intermittent catheters several times a day.

Catheters are useful devices, providing users with independence and freedom to self-catheterise as and when required, without having to rely on trained personnel to be present. This, however, increases the need for catheters to be user friendly: in particular, both easy to insert and remove with minimum discomfort caused, and safe to use with features for minimising risk of infection. Users often report experiencing pain and discomfort upon insertion and/or removal of catheters. Users have, for instance, reported experiencing bladder spasms, burning sensations, and bleeding.

It is also easy for catheters to become contaminated and for bacteria to be introduced into the urethra and along the urimu-y tract. As a result, urinary tract infections (UTI) are common in individuals who practice self-catheterisation.

Based on the above, urinary catheters, especially intermittent catheters, are typically single-use items. A user will remove the catheter from a package, use the catheter once, and then dispose of the catheter and package. This can be undesirable as it generates unwanted waste. Reusable urinary catheters could, thus, be advantageous is reducing the amount of waste created, but there are various challenges associated with the use of reusable catheters, such as issues surrounding storage, sterilisation and lubrication of the catheters, which need to be overcome before widespread acceptance and use of reusable catheters.

Sterilisation and lubrication of reusable catheters are two especially important factors, yet IS effective sterilisation and lubrication of reusable catheters has been notoriously difficult to achieve in practice.

There is a particular need for new solutions to the above challenges which allow for safe and effective reuse of catheters.

It is an aim of embodiments of the present invention to address one or more of the above 20 problems by providing a setup for reusable catheterisation which provides one or more of the following advantages: * Allows for simple and effective catheter sterilisation.

* Allows for simple and effective catheter lubrication.

* Allows for comhined sterilisation and lubrication.

* Allows for the catheter to be reused safely for long time periods.

* Does not require too frequent re-sterilisation and/or re-lubrication.

* Allows for a reduced likelihood of infections c.f. reusable setups of the prior art.

* Allows for a high lubricity, non-stick catheter surface to be maintained even after reuse. Allows for maintained ease of insertion and removal of the catheter even after reuse.

* Allows for an inert and sterile catheter surface to be maintained even after reuse.

* Allows for maintained catheter performance even after reuse.

* Not overly complex setup and simple/cost-effective to implement.

It is also all aim of embodiments of the invention to overcome or mitigate at least one problem of the prior art, whether expressly described herein or not.

Summary of the Invention

According to a first aspect of the invention, there is provided a reusable urinary catheter kit comprising a container comprising: a urinary catheter; and a medium comprising at least one species independently selected from the group comprising: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof.

The medium containing such chlorine-based species allows for effective sterilisation and/or lubrication of the catheter, which can be achieved by simply contacting the catheter with the medium. Further, use of such a medium causes minimal change to the relevant surface chemistry of the catheter upon contact, and so allows for catheter multiuse without adversely impacting catheter lubricity. The medium also provides for longterm sterilisation and/or lubrication, allowing the catheter to be reused safely for relatively long time periods without the need for overly frequent re-sterilisation and/or re-lubrication and without the need to replace medium too frequently.

In some embodiments, the medium comprises at least one species independently selected from the group consisting of: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof.

In some embodiments, the catheter comprises a hollow tubular body, preferably a hollow 10 polymeric tubular body. The hollow polymeric tubular body may comprise a base polymer.

In some embodiments, the catheter further comprises at least one additive, preferably at least one lubricious additive. Preferably, the hollow tubular body comprises at least one additive.

Additives allow for improved catheter lubricity and ease of insertion and removal.

However, the use of additives on a catheter, particularly on a surface thereof, provides the catheter with complex surface chemistry which can make catheter sterilisation and repeated lubrication challenging. Such catheters have, for instance, been known to swell upon wetting during sterilisation. Such catheters are also known to suffer from dry-out, which can result in considerable changes to the catheter surface morphology. As a result, catheters can become rough and sticky, and much more prone to additive delamination. The above negatives are typically severely amplified with catheter reuse. However, a medium containing the chlorine-based species of the invention allows for effective catheter sterilisation andior lubrication, which allows for prolonged effects of the additives. Accordingly, such a medium allows for safe and simple catheter use, with excellent performance in relation to reducing pain and discomfort.

In some embodiments, at least one additive is a hydrophilic additive.

At least one hydrophilic additive may be independently selected from the group comprising: a polyalkylene glycol, hyaluronic acid, chondroitan sulfate, chitosan, ducosaminoglucans, dextran, dextrin, dextran sulfate, cellulose acetate, carboxymethyl cellulose, hydroxyethyl cellulose, cellulosics, polypeptides, poly(2-hydroxyethyl methacrylate), polyacrylamide, polyacrylimide, poly(ethylene amine), poly(ally1 amine), polyvinyl pyrrolidone) (PVP), poly(vinyl alcohol), poly(acrylic acid), poly(methacrylic acid), acrylic acid copolymers, methacrylic acid copolymers, polyvinyl alkyl ethers, nonionic tetrafunctional block-copolymer surfactants, gelatin, collagen, albumin chitin, heparin, elastin, fibrin, and combinations thereof In some embodiments, at least one hydrophilic additive is independently selected from the group comprising: poly(ethylene glycol), poly(ethylene oxide), poly(propylene glycol), poly(ethylene oxide-co-propylene oxide), poly(trirnethylene glycol), poly(tetramethylene glycol), and combinations thereof.

At least one hydrophilic additive may comprise PVP or a derivative thereof.

At least one additive may be an amphiphilic additive. The amphiphilic additive comprises a hydrophobic portion and a hydrophilic portion. In cases where the base polymer is hydrophobic or generally hydrophobic, such as a pol yole fin, the amphiphilic additive will diffuse towards and to an outer surface of the catheter body due to incompatibility of the hydrophilic portion of the amphiphilic additive with the hydrophobic base polymer.

Amphiphilic additives, in particular those described below, further allow a hydration layer to be created through temporary hydrogen bonds on the catheter surface with water molecules and the chlorine-based species. As such, the catheter is able to remain sterile and lubricated for long periods of time and minimal to no changes to surface morphology are seen during sterilisation/lubrication and during catheter thy-out.

In some embodiments, the catheter comprises a hollow polymeric tubular body comprising a base polymer and an amphiphilic lubricious additive.

In some embodiments, at least one additive is polymeric or oligomeric.

At least one additive may be an A-B block copolymer comprising a hydrophobic hydrocarbon A-block and a hydrophilic B-block. In some embodiments, one or both of the hydrophobic hydrocarbon A-block and the hydrophilic B-block may be branched. The hydrophobic A-block may comprise hydrophobic hydrocarbon chains branching therefrom. The hydrophobic hydrocarbon chains may be of shorter chain lengths than the hydrophobic hydrocarbon A-block. The hydrophilic B-block may comprise further hydrophilic B-blocks branching therefrom.

In some embodiments, the additive is a B-A-B tri-block copolymer comprising a hydrophobic hydrocarbon A-block and hydrophilic B-blocks.

In other embodiments, the additive is a graft copolymer. The graft copolymer may comprise a hydrophobic hydrocarbon A-block with hydrophilic B-blocks branching 20 therefrom. Alternatively, the graft copolymer may comprise a hydrophilic portion with hydrophobic portions branching therefrom.

In further embodiments, the additive is a brush copolymer. The additive may comprise a single hydrophilic B-block with more than one hydrophobic A-block branching from an end thereof Alternatively, the additive may comprise a single hydrophobic A-block with more than one hydrophilic B-block branching from an end thereof. hi the respective embodiments, the B-block or A-block may comprise 2, 3, 4, 5, 6, 7, 8, 9, 10, or more hydrophobic A-blocks or hydrophilic B-blocks branching from the end thereof In further embodiments, the additive is a star-block or multi-block copolymer comprising hydrophilic and hydrophobic monomer units.

In preferred embodiments, the additive is an A-B block copolymer comprising a hydrophobic A-block and a hydrophilic B-block.

Statements of invention below relating to the additive or a part thereof may be applied 10 tnutatis mutandis to each of the copolymer forms above.

In some embodiments, the B-block is a hydrophilic oligomer comprising at least 1, 2, 3, 4, or at least 5 monomer units. In some embodiments, the B-block comprises no greater than 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10,9, 8,7, or no greater than 6 monomer units. In some embodiments, the B-Hock comprises between 2 and 15 monomer units, preferably between 2 and 10 monomer units. At least one monomer unit may be selected from the group comprising: alkylene oxides, alkylene glycols, epihalohydrins, unsaturated carboxylic acids, alkylene i mines, lactones, vinyl alcohol, and vinyl alkanoates. At least one monomer unit may be preferably selected from the group comprising: ethylene oxide, propylene oxide, ethylene dycol, propylene glycol, cpichlorohydrin, acrylic acid, methacrylic acid, ethylene iminc, caprolactone. vinyl alcohol, and vinyl acetate. hi some embodiments, at least one monomer unit comprises alkylene oxide groups independently selected from ethylene oxide and propylene oxide, and in preferred embodiments, all of the monomer units are ethylene oxide or all of the monomer units are propylene oxide.

The hydrophobic A-block may comprise a carbon chain of at least 5 carbon atoms, or at least 10, 15, 20, 25, 30, 35, or 40 carbon atoms. The hydrophobic portion may preferably comprise a carbon chain of between 20-52 carbon atoms.

In some embodiments, the A-block comprises a hydrocarbon chain block of the formula CH3CH2(CI-I2CH2)". The value of "a" may be between 5-25; for instance, -a" may be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25, or a half integer of any of the above values. The value of "a" may preferably be between 9-25; for instance, "a" may be 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25, or a half integer of any of the above values.

In some embodiments, the additive is homogenously distributed with the polymer. The additive may be uniformly distributed throughout the base polymer of the catheter body.

At least some of the additive may be at or on the outer surface of the body. By "at the outer surface it is meant that at least a portion of the additive forms part of the surface or protrudes from the surface. In some embodiments, part of the additive is retained or anchored in the body while part of the additive forms part of or protrudes from the outer surface of the body. At least part of the hydrophilic portion of the additive may protrude from or form part of the outer surface of the body, while at least part of the hydrophobic portion may be retained or anchored within the body.

The outer surface may comprise at least one member of the group comprising: the external-facing surface of the body, the lumen of the body and any eyelets present on the body. In preferred embodiments the outer surface is the external-facing surface of the body and/or the inner lumen. In some embodiments, the outer surface may comprise the external-facing surface of the body of the catheter, the inner lumen, and the eyelets.

The additive may be concentrated at or on the outer surface of the body. For example, at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or at least 95% of the number of molecules of the additive may heat or on the outer surface of the body.

In some embodiments, at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or at least 95% of the number of molecules of additive may have hydrophilic portions that are at or on the outer surface of the body.

In some embodiments, the additive is located at and/or on at least 50. 55. 60, 65, 70. 75, 80, 85, 90, 95, 96, 97, 98 or at least 99% of the outer surface area of the polymeric tubular body, preferably at least 75% or at least 90% of the outer surface area of the polymeric tubular body or between 75% and 100% of the outer surface area.

In some embodiments, the additive is present at a concentration of at least 0.1, 0.2, 0.3.

0.4. 0.5, 0.75, 1, 2, 3, 4, 5, 10, 15 or at least 20% by weight of the combination of base polymer and additive. The additive may be present a concentration of between 0.1-20%, and more preferably between 0.5-15% or 0.5-5% by weight of the combination of base polymer and additive.

In some embodiments, the additive comprises a layer that is on or that comprises a surface of the body, preferably the outer surface.

The layer comprising the additive may be on the surface of the body. In some embodiments, the layer comprising the additive is substantially separate from the body and the layer may be bonded to the body. The layer may be bonded to the body via covalent bonds, ionic bonds, hydrogen bonds, or Van der Waals forces. The additive may be bonded to the body via one or more surface linker groups which may be present on the additive, the body of the catheter or both.

In some embodiments, the layer comprising the additive may commise the surface of the body. In such embodiments the layer may form the surface of the body. The layer may comprise a co-extruded layer which is melded with or is physically entangled with the body, and this may form an integral layer. The layer of additive may be integrally formed with the body.

In some embodiments, polymer diffusion occurs between the layer comprising the additive and the catheter body. The layer and the body may be held together by polymer chains extending across the interface between the layer and body. In some embodiments, the additive infiltrates the catheter body.

In some embodiments, the layer comprising the additive comprises or is on an inner surface of the body, an outer surface of the body, or both. The inner surface of the body IS may comprise a lumen of the catheter. In preferred embodiments, the layer comprising the additive comprises or is on at least an outer surface of the body.

In some embodiments, the layer comprising the additive is on or comprises at least 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98 or at least 99% of the or each surface area of the body, preferably at least 75% or at least 90% of the or each surface area or between 75% and 100% of the or each surface area. In embodiments in which the layer comprising the additive comprises or is on both an inner and outer surface of the body, the additive may comprise at least 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98 or at

I I

least 99% of each surface area of the body, preferably at least 75% or at least 90% of each surface area or between 75% and 100% of each surface area of both surfaces.

In some embodiments, at least 75% of the layer comprising the additive, or at least 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% of the layer is the additive.

In some embodiments, the layer comprising the additive has an additive concentration of at least 0.1, 0.2, 0.3. 0.4. 0.5, 0.75, 1, 2, 3, 4, 5, 10, 15 or at least 20% by weight of the combination of base polymer and additive.

In some embodiments, the layer comprising the additive has an additive concentration of 10 no greater than 70, 65, 60, 65, 60, 55. or of no greater than 50% by weight of the combination of the base polymer and additive.

The layer comprising the additive may have an additive concentration of greater than 5% by weight of the combination of the base polymer and additive. The layer may have an additive concentration of between 6-50% by weight of the combination of the base polymer and additive.

The layer comprising the additive may have an additive concentration of between 1050% by weight of the combination of the base polymer and additive, or of between 1550, 20-50, 25-50, 30-50, 35-50, 40-50, or of between 45-50% by weight of the combination of the base polymer and additive.

The layer comprising the additive may have an additive concentration of between 6-45% by weight of the combination of the base polymer and additive, or of between 6-40, 6-35, 6-30, 6-25, 6-20, 6-15, or of between 6-10% by weight of the combination of the base polymer and additive.

The layer comprising the additive may have an additive concentration of between 1045% by weight of the combination of the base polymer and additive, or of between 15-45, 20-45, 25-45, 30-45, 35-45, 40-45, 10-40, 15-40, 20-40, 25-40, 30-40, 35-40, 10-35, 15-35, 20-35, 25-35, 30-35, 10-30, 15-30, 20-30, 25-30, 10-25, 15-25,20-25, 10-20, 15- 20, or of between 10-15% by weight of the combination of the base polymer and additive.

In some embodiments, the layer comprising the additive has a thickness of at least 1 pm, or of at least 2, 3.4. 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40,45, or of at least 50 pm.

In some embodiments, the layer comprising the additive has a thickness of no more than 10000 pm, or of no more than 9000, 8000, 7000, 6000, 5000, 4000, 3000, 2000, 1000, 900, 800, 700, 600, 500, 400, or of no more than 300 p m.

In some embodiments, the layer comprising the additive has a thickness of between 50300 gm.

The layer comprising the additive may have a thickness of between 60-300 p m, or of between 80-300, 100-300, 120-300, 140-300, 160-300, 180-300, 200-300. 220-300, 240- 300, 260-300, or of between 280-300 pm.

The layer comprising the additive may have a thickness of between 50-280 pm, or of between 50-260, 50-240, 50-220, 50-200, 50-180, 50-160, 50-140, 50-120, 50-100, 5080, or of between 50-60 pm.

The layer comprising the additive may have a thickness of between 60-280 p m, or of between 80-280, 100-280, 120-280, 140-280, 160-280, 180-280, 200-280. 220-280, 240- 280, 260-280, 60-260, 80-260, 100-260, 120-260, 140-260, 160-260, 180-260, 200-260, 220-260, 240-260, 60-240, 80-240, 100-240, 120-240, 140-240, 160-240, 180-240, 200- 240.220-240. 60-220, 80-220, 100-220, 120-220, 140-220, 160-220, 180-220, 200-220, 60-200, 80-200, 100-200, 120-200, 140-200, 160-200, 180-200, 60-180, 80-180, 100180, 120-180, 140-180, 160-180, 60-160, 80-160, 100-160, 120-160, 140-160, 60-140, 80-140, 100-140, 120-140, 60-120, 80-120, 100-120, 60-100, 80-100, or of between 60-80 pm.

In preferred embodiments, the catheter base polymer is hydrophobic or partly hydrophobic. A hydrophobic base polymer facilitates increased hydrophobic-hydrophobic interactions between the hydrophobic portion of the additive and the base polymer. This further decreases the energetic favourability for the hydrophobic portion to leave the base polymer and migrate out into the more hydrophilic external environment.

In some embodiments, the base polymer comprises a polymer selected from the group consisting of: polyvinyl chloride, polytetrafluoroethylene, polyolefins, latex, silicones, synthetic rubbers, polyurethanes, polyesters, polyacrylates, polyamides, thermoplastic elastomeric materials, styrene block copolymers, polyether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, styrene-butadiene copolymer (SBC), styrene-ethylene-butylene-styrene copolymer (SEBS), and water disintegrable or enzymatically hydrolysable material, or combinations, blends or copolymers of any of the above materials.

In preferred embodiments, the base polymer comprises a polymer selected from the group consisting of: polyolefins, polyesters, polyacrylates, polyamides, thermoplastic elastomeric material, polyether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, fluororubber, and water disintegrable or enzymatically hydrolysable material or combinations, blends or copolymers of any of the above materials.

In some embodiments, said water disintegrable or enzymatically hydrolysable material comprises a material of the group consisting of: polyvinyl alcohol, extnidable polyvinyl alcohol, polyacrylic acids, polylactic acid, polyesters, polyglycol ide, polyglycol ic acid, poly lactic-co-glycolic acid, polylactide, amines, polyacrylamides, poly(N-(2-Hydroxypropyl) methacrylamide), starch, modified starches or derivatives, amylopectin, pectin, xanthan, scleroglucan, dextrin, chitosans, chitins, agar, alginate, carrageenans, laminarin, saccharides, polysaccharides, sucrose, polyethylene oxide, polypropylene oxide, acrylics, polyacrylic acid blends, poly(methacrylic acid), polystyrene sulfonate, polyethylene sulfonate, lignin sulfonate, polymethacrylamides, copolymers of aminoalkyl-acrylamides and methacrylamides, melamine-formaldehyde copolymers, vinyl alcohol copolymers, cellulose ethers, poly-ethers, polyethylene oxide, blends of polyethylene-polypropylene glycol, carboxy methyl cellulose, guar gum, locust bean gum, hydroxypropyl cellulose, vinylpyrrolidone polymers and copolymers, polyvinyl pyrrolidone-ethylene-vinyl acetate, polyvinyl pyn-olidone-carboxymethyl cellulose, carboxymethyl cellulose shellac, copolymers of vinylpyrrolidone with vinyl acetate, hydroxyethyl cellulose, gelatin, poly-caprolactone, poly(p-dioxanone), or combinations, blends or co-polymers of any of the above materials.

In other preferred embodiments, the base polymer comprises a polymer selected from the group consisting of: polyolefins, polyvinyl chloride, polyurethane, styrene-butadiene copolymer (S BC), sty rene-ethyl ene-butylen e-styrene copolymer (SEBS) and thermoplastic elastomeric material or combinations, blends or copolymers of any of the above materials.

In some preferred embodiments, the base polymer comprises a polyolefin, especially polyethylene and/or polypropylene.

In some preferred embodiments, the base polymer comprises a thermoplastic elastomeric material. The base polymer may comprise a thermoplastic polyolefin.

The thermoplastic base polymer may comprise a hydrophobic polymer selected from the group consisting of: Accurel TM, StyroflexTM, StyroluxTm, MelileXTM. and MedipreneTm and any combination thereof.

The thermoplastic base polymer may comprise EstaneTM 58315, which is both hydrophobic and hydrophilic.

In prefened embodiments, the catheter is an intermittent urinary catheter. Such a catheter is typically inserted into a body for short time periods, such as less than a day. Alternatively, the catheter may be an indwelling (Foley) catheter. Such a catheter is typically inserted and kept in a body for long periods of time, such as several days to months.

In some embodiments, the medium comprises chlorine dioxide. In some embodiments, the medium comprises hypochlorous acid.

In some embodiments, the medium comprises at least one hypochlorite salt. At least one hypochlorite salt may preferably comprise a countercation. The countercation may comprise an inorganic countercation. The countercation may comprise a metal countercation. In some embodiments, at least one countercation is independently selected from the group consisting of: an alkali metal cation, an alkaline earth metal cation, a group In metal cation, a transition metal cation, an ammonium cation, an aromatic nitrogen-based cation, and combinations thereof At least one countercation may be independently selected from the group consisting of: ammonium, calcium, iron, magnesium, potassium, pyridinium, quaternary ammonium, sodium, copper, aluminium, lithium, beryllium strontium,and zinc. At least one countercation may preferably be an alkali metal cation or an alkaline earth metal cation. At least one countercation may preferably be independently selected from the group consisting of: calcium, lithium, and sodium. In preferred embodiments, at least one hypochlorite salt is sodium hypochlorite.

In some embodiments, the medium comprises hypochlorous acid and at least one hypochlorite salt. At least one hypochlorite salt may preferably be as described in statements of invention above. The medium may preferably comprise hypochlorous acid and at least one alkali metal hypochlorite salt. In some embodiments, the medium comprises hypochlorous acid and sodium hypochlorite.

In embodiments wherein the medium comprises hypochlorous acid and at least one hypochlorite salt, the pH of the medium may preferably be between 6-9.

In some embodiments, the medium comprises chlorine dioxide and at least one of: hypochlorous acid and at least one hypochlorite salt. In some embodiments, the medium comprises chlorine dioxide, hypochlorous acid, and at least one hypochlorite salt. In such embodiments, at least one hypochlorite salt may preferably be as described in statements of invention above. At least one hypochlorite salt may preferably be an alkali metal hypochlorite salt, which may comprise sodium hypochlorite.

In some embodiments, the medium is present in liquid, gel or solid form.

In some embodiments, the medium is present as a solution of the inventive chlorine-based species in a solvent. The solution may be an aqueous solution. Aqueous solutions are particularly effective, as water allows for optimal catheter surface lubricity. The solvent may therefore be water or an aqueous medium.

In some embodiments, the medium comprises chlorine dioxide in a total concentration of at least 0.005 wt.% of the medium, or at least 0.006, 0.007, 0.008, 0.009, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, or at least 0.2 wt.% of the medium.

In some embodiments, the medium comprises chlorine dioxide in a total combined concentration of no greater than 5 wt.% of the medium, or no greater than 4 5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4,0.3, or no greater than 0.2 wt.% of the medium.

In some embodiments, the medium comprises chlorine dioxide in a total combined concentration of between 0.005-1.5 wt.% of the medium, or between 0.005-1, or between 0.005-0.6 wt.% of the medium, or between 0.01-0.5, 0.015-0.4, 0.02-0.3, or between 0.025-0.2 wt.% of the medium, or preferably between 0.025-0.1 wt.% of the medium.

In some embodiments, the medium comprises one or more of: chlorine dioxide, hypochlorous acid, and at least one hypochlorite in a total combined concentration of at least 0.005 wt.% of the medium, or at least 0.006, 0.007, 0.008, 0.009. 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, or at least 0.2 wt.% of the medium.

In some embodiments, the medium comprises one or more of: chlorine dioxide, hypochlorous acid, and at least one hypochlorite salt in a total combined concentration of no greater than 5 wt.% of the medium, or no greater than 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1,0.9, 0.8, 0.7, 0.6, 0.5, 0.4,0.3, or no greater than 0.2 wt.% of the medium.

In some embodiments, the medium comprises one or more of: chlorine dioxide, hypochlorous acid, and at least one hypochlorite salt in a total combined concentration of between 0.005-1.5 wt.% of the medium, or between 0.005-1, or betvveen 0.005-0.6 wt.% of the medium, or between 0.01-0.5, 0.015-0.4, 0.02-0.3, or between 0.025-0.2 wt.% of the medium, or preferably between 0.025-0.1 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid and/or at least one hypochlorite in a total combined concentration of at least 0.005 wt.% of the medium, or at least 0.006, 0.007, 0.008, 0.009, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, or at least 0.2 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid and/or at least one hypochlorite sal( in a total combined concentration of no greater than 5 wt.% of the IS medium, or no greater than 4.5, 4.3.5, 3,2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, or no greater than 0.2 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid and/or at least one hypochlorite salt in a total combined concentration of between 0.005-1.5 wt.% of the medium, or between 0.005-1, or between 0.005-0.6 wt.% of the medium, or between 0.01-0.5, 0.015-0.4. 0.02-0.3. or between 0.025-0.2 wt.% of the medium, or preferably between 0.025-0.1 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid in a total concentration of at least 0.005 wt.% of the medium, or at least 0.006, 0.007, 0.008, 0.009, 0.01, 0.015, 0.02, 0.025. 0.03, 0.035, 0.04, 0.045. 0.05, 0.055, 0.06, or preferably at least 0.065,0.07, 0.075, 0.08. 0.085, 0.09, 0.095, 0.1. 0.11, 0.12, 0.13, 0.14, 0.15. 0.16. 0.17, 0.18, 0.19, or at least 0.2 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid in a total concentration of no greater than 5 wt.% of the medium, or no greater than 4.5.4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, or no greater than 0.2 wt.% of the medium.

In some embodiments, the medium comprises hypochlorous acid in a total concentration of between 0.005-1.5 wt.% of the medium, or between 0.005-1, or between 0.005-0.6 wt.% of the medium, or between 0.01-0.5, 0.015-0.4, 0.02-0.3, or between 0.025-0.2 wt.% of the medium, or between 0.025-0.1 wt.% of the medium.

The medium may comprise the hypochlorite salt in a total concentration of at least 0.005 wt.% of the medium, or at least 0.006, 0.007, 0.008, 0.009, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, or at least 0.2 wt.% of the medium.

In some embodiments, the medium comprises the hypochlorite salt in a total concentration of no greater than 5 wt.% of the medium, or no greater than 4 5 4, 3 5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4,0.3. or no greater than 0.2 wt.% of the medium.

In some embodiments, the medium comprises the hypochlorite salt in a total concentration of between 0.005-1.5 wt.% of the medium, or between 0.005-1, or between 0.005-0.6 wt.% of the medium, or between 0.01-0.5, 0.015-0.4, 0.02-0.3, or between 0.025-0.2 wt.% of the medium, or between 0.025-0.1 wt.% of the medium.

In some embodiments, the medium is present in a total amount of at least 0.05 wt.% of the combination of the catheter and medium, or of at least 0.1, 0.15, 0.2, 0.25, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9.0.95, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, or at least 20 wt.% of the combination of the catheter and medium.

The medium may be present in a total amount of no greater than 40 wt.% of the combination of the catheter and medium, or no greater than 35, 30, 25, 20, 15, 10, or no greater than 5 wt.% of the combination of the catheter and medium.

The medium may be present in a total amount of between 0.1-20 wt.% of the combination of the catheter and medium, or between 0.5-15, or between 0.5-5 wt.% of the combination of the catheter and medium.

In some embodiments, the medium is present as a liquid having a viscosity of greater than 0.5 cP, or of greater than 1, 1.5. 2. 3, 4. 5, 10, 20, 30. 40, 50. 75. 100. 150. 200, 300, 400, 500, 600, 700, 800, 900, or of greater than 1000 cP. The medium may have a viscosity of no greater than 100000 cP, or of no greater than 90000, 80000, 70000, 60000, 50000, 40000, 30000, 20000, 10000, 5000, 4000, 3000, 2000, 1000, 500, 400, 300, 200, 100, 50, 25, 10, 5,4, 3, 2, or of no greater than 1 cP. The medium may have a IS viscosity of between 0.5-5000 cP, or of between 0.5-2500, 0.5-1000, 1-1000, 10-1000, 50-1000, 100-1000, 500-1000, 0.5-500, 1-500, 10-500, 50-500, 100-500, 250-500, 0.5250, 1-250, 10-250, 50-250, or of between 100-250 cP.

The medium may be a catheter wetting agent. The medium may encourage hydrophilic portions of lubricating additives within the catheter to seek towards an outer surface of the catheter, which further enhances the lubricating effect of the additive.

In some embodiments, the medium has a pH of at least 2,2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7,7.5, 8,8.5, or of no greater than 9. In some embodiments, the medium may have a pH of no greater than 14, or of no greater than 13.5, 13, 12.5, 12, 11.5, 11, 10.5, or of no greater than 10.

In some embodiments, the medium has a pH of between 2-14, 3-13, or of between 4-12.

M some embodiments the medium comprises at least one further species that is independently selected from the group consisting of: a chlorine-containing bleaching and/or oxidising agent, a peroxide species, a base, an acid, a photosensitiser, a permanganate species an alcohol, a phenol, an aldehyde, ionic silver, molecular iodine or an iodophor, an imine-containing species, a salt and combinations thereof In some embodiments, the medium comprising at least one further chlorine-containing bleaching and/or oxidising agent that is independently selected from the group consisting of: molecular chlorine, a clichloroisocyanurate salt, chloroazodin, dichlorodimethylhydantoin, chloroxylenol, chlorhexidine, and combinations thereof.

In some embodiments, the total concentration of chlorine-containing bleaching and/or oxidising agents in the medium is between 0.05-0.6 wt.% of the medium or between 0.01-0.5, 0.015-0.4, 0.02-0.3, or between 0.025-0.2 wt.% of the medium, or between 0.025-0.1 w t.%.

In preferred embodiments, the medium comprises molecular chlorine. In some embodiments, the medium comprises at least one hypochlorite salt and molecular chlorine. In preferred embodiments, the medium comprises hypochlorous acid and molecular chlorine. In some embodiments, the medium comprises hypochlorous acid, molecular chlorine, and at least one hypochlorite salt.

In some embodiments, the medium has a pH of less than 4, and the amount of molecular chlorine in the medium is greater than the total combined amount of hypochlorous acid and hypochlorite salt..

In some embodiments, the medium has a pH of between 4-7, and the amount of hypochlorous acid in the medium is greater than the total combined amount of molecular chlorine and hypochlorite salt.

In some embodiments, the medium has a pH of greater than 8, and the amount of hypochlorite salt in the medium is greater than the total combined amount of molecular chlorine and hypochlorous acid.

The medium may comprise at least one further salt (in addition to any hypochlorite salt present). At least one salt may comprise a cation that is independently selected from the group consisting of: ammonium, calcium iron, magnesium, potassium, pyridinium, quaternary ammonium, sodium, copper, aluminium, lithium, beryllium, strontium, and zinc. At least. one salt may preferably comprise an alkali metal cation. At least one salt.

IS may comprise an anion that is independently selected from the group consisting of: acetate, carbonate, bicarbonate, chloride, citrate, glutamate, fluoride, bromide, iodide, nitrate, nitrite, oxide, phosphate, ferrocyanide, silicate, aluconate, and sulfate. At least one salt may preferably comprise a halide anion.

At least one of the further salts may be independently selected from the group consisting: sodium chloride, potassium chloride, calcium chloride, magnesium chloride, calcium chloride, sodium nitrite, magnesium nitrate, calcium nitrate, potassium carbonate, sodium carbonate, sodium bicarbonate, potassium iodide, copper iodide, sodium ferrocyanide, monosodium glutamate, calcium silicate, sodium citrate, potassium citrate, sodium phosphate, potassium phosphate, sodium sulfate, calcium sulfate, sodium gluconate, calcium gluconate, potassium gluconate, sodium acetate, and potassium acetate.

At least one of the further salts may preferably be an alkali metal halide. At least one salt may be independently selected from the group consisting of: an alkali metal chloride, an alkali metal bromide, an alkali metal iodide, and combinations thereof Preferably, the medium may comprise an alkali metal salt and a hypochlorite salt. The medium may comprise a halide salt and a hypochlorite salt. The medium may comprise an alkali metal halide and a hypochlorite salt.

In a particularly preferred embodiment, the medium comprises sodium chloride. The 10 medium may preferably comprise a hypochlorite salt and sodium chloride, preferably an alkali metal hypochlorite and sodium chloride, and more preferably sodium hypochlorite and sodium chloride.

In some embodiments, the total concentration of further salt in the medium is between 530 wt.%, or of between 10-25, or of between 10-20 wt.% of the medium.

In some embodiments, the medium comprises teh hypochlorite sal( in a total concentration of between 0.25-2 wt.%, or 0.5-1.5 wt.% of the medium, and the further salt in a total concentration of between 5-30, 10-25, or between 10-20 wt.% of the medium.

In some embodiments, the ratio of the total concentration of further sal( to hypochlorite salt in the medium is at least 5, or at least 10, or at least 15. The ratio of the total concentration of further salt to hypochlorite salt in the medium may be between 5-30, or between 10-25, or between 10-20.

In some embodiments, the medium further comprises at least one base.

At least one base may comprise an inorganic base. At least one inorganic base may be independently selected from the group consisting of: a hydroxide base, a carbonate base, a bicarbonate base, and combinations thereof. In some preferred embodiments, at least one base is a hydroxide base. At least one hydroxide base may be independently selected from the group consisting of: an alkali metal hydroxide, an alkaline earth metal hydroxide, a group III metal hydroxide, a transition metal hydroxide, and combinations thereof. At least one hydroxide base may preferably comprise an alkali metal hydroxide and/or an alkaline earth metal hydroxide. In some embodiments, at least one base comprises an alkali metal hydroxide that is independently selected from the group comprising: lithium hydroxide, sodium hydroxide, potassium hydroxide, and combinations thereof.

Preferably, the medium may comprise an alkali metal base and a hypochlorite salt. The medium may comprise a hydroxide base and a hypochlorite salt. The medium may comprise an alkali metal hydroxide and a hypochlorite salt.

In a particularly preferred embodiment, the base comprises sodium hydroxide. The medium may preferably comprise a hypochlorite salt and sodium hydroxide, preferably an alkali metal hypochlorite and sodium hydroxide, and more preferably sodium hypochlorite and sodium hydroxide.

In some embodiments, the medium comprises at least one acid that is a carboxylic acid. In some embodiments, the medium comprises at least one acid that is independently selected from the group consisting of: acetic acid, citric acid, peracetic acid, diperoxy dodecanoic acid, and combinations thereof In some embodiments, the medium comprises at least one CI -C10 alcohol, or at least one C 1-05 alcohol, or at least one C 1-C3 alcohol. In some embodiments, the medium comprises at least one alcohol that is independently selected from the group consisting of: ethanol, isopropanol, and combinations thereof.

In some embodiments, the medium comprises at least one phenol that is independently selected from the group consisting of: phenol, thymol, chloroxylenol, and combinations thereof.

In some embodiments, the medium comprises at least one aldehyde that is independently selected from the group consisting of: glutaraldehyde, noxytiolin, and combinations 10 thereof.

In some embodiments, the medium comprises at least one imine-containing species that is independently selected from: polyhexanide, octenidine, and combinations thereof In some embodiments, the container is a case. The case may preferably define a cavity configured to hold the catheter.

In some embodiments, the case is rigid. In other embodiments, the case is flexible. In some embodiments, the case contains rigid and flexible regions. The case may comprise a tube. The tube may have a flexible centre portion and two rigid side portions neighbouring the flexible centre portion.

The catheter may preferably be configured to be repeatedly inserted and removed from the container.

In some embodiments, the medium is in direct contact. with the catheter. The medium may be in direct contact with at least one surface of the catheter. The at least one surface may comprise the outer surface of the catheter. The medium may cover at least part of the outer surface of the catheter.

The at least one surface may comprise an inner surface of the catheter and the medium may cover at least part of the inner surface.

In some embodiments, the catheter is submerged in the medium. Submersion of the catheter in the medium has been shown to confer optimal catheter lubricity.

The catheter may be fully submerged in the medium. In such embodiments, the medium may comprise at least 30% of the internal volume of the container, or at least 40, 50, 60, 70, 80, 90, or at least 95% of the internal volume of the container.

In some embodiments, the catheter is not fully submerged in the medium. In such embodiments, the medium may comprise no greater than 30% of the internal volume of the container, or no greater than 25, 20, 15, 10, 5, 4, 3, 2, or no greater than 1% of the internal volume of the container. In such embodiments, the medium may be in direct contact with at least part of the catheter, preferably with at least one surface thereof. In some embodiments, the medium may be able to move freely within the container. In such embodiments, the medium may be configured to slosh around within the container, such as when the container is shaken and/or due to natural movement of the container by the user.

In some embodiments, the catheter comprises a layer of the medium that is on or that comprises at least part of a surface of the catheter, preferably at least part of the outer surface of the catheter. In such embodiments, the medium may be a liquid or a gel.

The layer of medium may preferably be on the surface of the catheter, preferably on the surface of the catheter body.

In some embodiments, the layer is on an inner surface of the catheter, an outer surface of the catheter, or both. The inner surface of the catheter may comprise a lumen of the catheter. In preferred embodiments, the layer is on at least an outer surface of the catheter.

In some embodiments, the layer is on at least 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97,98, or at least 99% of the or each surface area of the catheter, preferably at least 75%, or at least 90% of the or each surface area, or between 75% and 100% of the or each surface area. In embodiments in which the layer is on both an inner and outer surface of the catheter, the additive may be on or comprise at least 50, 55, 60, 65, 70,75, 80, 85, 90, 95, 96,97, 98 or at least 99% of each surface area of the catheter, preferably at least 75% or at least 90% of each surface area or between 75% and 100% of each surface area of both surfaces.

In some embodiments, at least 75% of the layer, or at least 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% of the layer is the 15 medium.

In some embodiments, the layer has a thickness of at least 1 gm, or of at least 2, 3, 4, 5, 6,7, 8.9, 10, 15, 20,25, 30, 35, 40, 45, or of at least 50 pm.

In some embodiments, the layer has a thickness of no greater than 10000 pm, or of no mater than 9000, 8000, 7000,6000. 5000.4000, 3000, 2000, 1000, 900, 800, 700, 600, 20 500, 400, or of no greater than 300 pm.

In some embodiments, the layer has a thickness of between 50-300 pm.

The layer may have a thickness of between 60-300 p m, or of between 80-300, 100-300, 120-300, 140-300, 160-300, 180-300, 200-300, 220-300, 240-300, 260-300, or of between 280-300 pm.

The layer may have a thickness of between 50-280 urn, or of between 50-260, 50-240, 50-220, 50-200, 50-180, 50-160, 50-140, 50-120, 50-100, 50-80, or of between 50-60 The layer may have a thickness of between 60-280 p m, or of between 80-280, 100-280, 120-280, 140-280, 160-280, 180-280, 200-280. 220-280, 240-280. 260-280, 60-260, 80- 260, 100-260, 120-260, 140-260, 160-260, 180-260, 200-260, 220-260, 240-260, 60-240, 80-240, 100-240, 120-240, 140-240, 160-240, 180-240, 200-240, 220-240, 60-220, 80- 220. 100-220, 120-220, 140-220, 160-220, 180-220, 200-220. 60-200. 80-200, 100-200. 120-200, 140-200, 160-200, 180-200, 60-180, 80-180, 100-180, 120-180, 140-180, 160-180, 60-160. 80-160, 100-160. 120-160, 140-160, 60-140, 80-140, 100-140, 120-140, 60120, 80-120, 100-120, 60-100, 80-100, or of between 60-80 pm.

The layer of medium may have a viscosity of at least 200 cP, or at least 400, 600, 800, or at least 1000 cP, or at least 1200, 1400, 1600, 1800. 2000, 2200, 2400, 2600, 2800. 3000.

3200, 3400, 3600, 3800, 4000, 4200, 4400, 4600, 4800, 5000, 5200, 5400, 5600, 5800, 6000, 6200, 6400, 6600, 6800, 7000, 7200, 7400, 7600, 7800, 8000, 8200, 8400, 8600, 8800, 9000, 9200, 9400, 9600, 9800, or at least 10000 cP.

The layer of medium may have a viscosity of no greater than 2000000. or no greater than 1750000. 1500000, 1250000, or no greater than 1000000 cP.

The layer of medium may have a viscosity of between 100-2000000, or between 500-1000000. or between 1000-500000 cP.

In some embodiments, the medium is contained in a medium container and the catheter is contained in a separate catheter container. The medium container may be a bag or sachet. The medium container may be located in the catheter container. In some embodiments, the medium is contained in a medium container located in the catheter container and the medium is not in direct contact with the catheter. In some embodiments, the medium container is pierceable, in use, to release the contained medium from the medium container and into direct contact with the catheter in the catheter container, preferably without requiring opening of the catheter container.

Prior to opening the catheter container, prior to removing the catheter and/or prior to 10 inserting the catheter, the user may release the medium from the medium container and apply the medium to the outer surface of the catheter.

In some embodiments, the catheter is submerged in a liquid and/or solution which does not contain the chlorine-based species of the invention, and the inventive chlorine-based species may be contained in a separate medium container. The separate medium container may be as described in statements of invention above.

The chlorine-based species of the invention may be present in the separate medium container in solid, liquid, or gel form. The liquid may comprise a solution comprising the chlorine-based species of the invention. In embodiments wherein the chlorine-based species of the invention are present in solid form, the solid may comprise a powder or at

least one tablet.

In such embodiments, the chlorine-based species of the invention may be releasable from the separate medium container, in use. The chlorine-based species of the invention may be used to treat the catheter after release from the medium container. In embodiments wherein the chlorine-based species of the invention is present in solid form, the solid may be dissolvable in a liquid to provide a solution comprising the chlorine-based species of the invention, which may be used to treat the catheter. The liquid may be the liquid in which the catheter is submerged.

In some embodiments, the reusable catheter may be configured to be reused at least 1 time, or at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or at least 20 times. The reusable catheter may be configured to be reused up to 5 times or up to 10, 15, 20, 25, 30, 35, 40,45, or up to 50 times.

In some embodiments, the reusable catheter may be configured to be reused for up to 1 day, or up to 2, 3, 4, 5, or up to 6 days, or up to 1 week, or up to 8 days, or up to 9, 10, 11, 12, or up to 13 days, or up to 2 weeks, or up to 3 weeks, or up to 1 month, or up to 2 months. The reusable catheter may be configured to be reused for up to between 1 day to 2 month, or up to between 1 week to 1.5 months, or for up to between 2 weeks to 1 month.

IS According to a second aspect of the invention, there is provided a method of sterilising and/or lubricating a reusable urinary catheter, the method comprising at least the steps of: (a) Providing a reusable urinary catheter; and (b) Treating the reusable urinary catheter with a medium comprising at least one species independently selected from the group comprising: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof The catheter of the second aspect of the invention is preferably the catheter of the first aspect of the invention. The medium of the second aspect of the invention may preferably be the medium of the first aspect of the invention.

Statements of invention above relating to the first aspect of the invention may also he applied mutatis tnutandis to the second aspect of the invention.

Statements of invention below relating to the second aspect of the invention may also be applied mutatis tnutandis to the other aspects of the present invention.

In some embodiments, the catheter in step (a) is provided before first use of the catheter.

In some embodiments, the catheter in step (a) is provided after first use of the catheter. Steps (a) and (h) may he repeated. In such embodiments step (a) may comprise providing an unused catheter, followed by step (b) and then catheter used, followed by providing the used catheter in a further step (a) and then performing step (b). Such repetition of step (a) and/or (h) may be completed a plurality of times In some embodiments, the method comprises a washing step before each step (b). In some embodiments, the washing step takes place directly before step (h). The washing step may comprise washing a surface of the catheter, preferably the outer surface thereof. in some embodiments, the washing step comprises washing the catheter with water. In some embodiments, the washing step comprises washing the catheter with an aqueous solution. The washing step may comprise washing the catheter with a detergent and with water or an aqueous solution. In some embodiments, the washing step comprises applying a detergent to the catheter, preferably to the outer surface thereof, and then rinsing the catheter with water or an aqueous solution.

Treatment in step (b) may involve one or more treatment methods independently selected from the group comprising: submersion, spray coating, soaking, dipping, wetting, and combinations thereof.

In some embodiments, step (b) comprises treating at least one surface of the catheter with the medium, preferably at least an outer surface of the catheter.

In some embodiments, step (b) comprises treating at least 20% of the outer surface area of the catheter with the medium, or at least 25, 30, 35, 40, 45, 50, 55, 60,65, 70, 75, 80, 85, 90, 95.96. 97, 98, or at least 99% of the outer surface area of the catheter, preferably at least 75%, or at least 90% of the outer surface area, or between 75% and 100% of the outer surface area of the catheter.

In some embodiments, step (b) comprises spraying the catheter with the medium. Step (b) may comprise spraying at least part of a surface of the catheter, preferably at least part of the outer surface of the catheter.

In some embodiments, step (b) comprises submerging the catheter in the medium.

Submerging the catheter in the medium, especially between uses, has been shown to result in optimal catheter lubricity.

In some embodiments, step (b) comprises treating the catheter with the medium for a total time of at least 5 seconds, or at least 10,20, 30,40, or at least 50 seconds, or at least I minute, or at least 2, 3,4. or at least 5 minutes, or at least 10, 20, 30, 40, or at least 50 minutes, or at least 1 hour, or at least 1.5,2, 2.5, 3, 3.5, or at least 4 hours. Step (b) may comprise treating the catheter with the medium for a total time of no greater than 1 week, or no greater than 6 days, or no greater than 5, 4, 3, 2, or no greater than 1 day, or no greater than 20 hours, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, or no greater than 5 hours.

In some embodiments, step (b) is performed at a temperature of at least 1 °C, or at least 2, 3, 4, or at least 5 °C. In some embodiments, step (b) is performed at a temperature of no greater than 60 'V, or no greater than 55, 50, 45, 40, 35, 30, or no greater than 25 'C. In some embodiments, step (b) is performed at a temperature of between 1-60 °C, or between 5-50, or between 10-40 °C.

In some embodiments, step (b) is performed when the catheter is held in a container. The container may preferably be the container of the first aspect of the invention. The container may comprise the medium. Step (b) may comprise placing the catheter into the container to bring the catheter into direct. contact with the medium. Step (b) may preferably comprise submerging the catheter in the medium. Step (b) may comprise placing the catheter in the container after each use of the catheter, and may preferably comprise submerging the catheter in the medium after each use of the catheter. There may be a plurality of containers containing medium, and each step (b) may comprise placing or submerging the catheter in a different medium container.

In some embodiments, the medium may be contained in a medium container and the catheter may be contained in a separate catheter container, preferably as described for the first aspect of the invention. Step (b) may comprise releasing the medium from the separate medium container, and then treating the catheter with the medium.

In some embodiments, the method is repeated at least once. The method may be performed before and/or after each use of the catheter. In some embodiments, the method is performed 3 times a day, or 2 times a day, or once a day, or once every 2 days, or once every 3 days, or once every 4 days, or once every 5 days, or once every 6 days, or once a week, or once every 2 weeks, or once every 3 weeks, or once a month.

In some embodiments, the or each step (b) comprises treating the catheter with fresh medium that has not been used previously to treat the catheter. In such embodiments, the medium may be replaced with fresh medium before and/or after each step (b).

In some embodiments, the medium may be replaced with fresh medium at least every 6-hour period, or at least every 12, 18, or at least after every 24 hour period.

Replenishing the medium in a catheter reuse scenario has been shown to be optimal with respect to both the effectiveness of catheter sterilisation and catheter lubricity.

In some embodiments, the method comprises a further step of lubricating the catheter with an additional lubricating agent. The further lubrication step may preferably be performed after step (b). In some embodiments, the catheter may be dried after step (b) and before the further lubrication step. The drying step may comprise air drying and/or wiping the catheter to dry the catheter. In some embodiments, the further lubrication step is performed before use of the catheter, preferably directly before use of the catheter. Preferably, the further lubrication step is performed after step (b) and before use of the IS catheter.

The additional lubricating agent may be water or may comprise water. The additional lubricating agent may be an aqueous solution.

The further lubrication step may comprise treating the catheter, preferably at least part of the outer surface thereof with the lubricating agent. The further lubrication step may comprise applying the lubricating agent to the catheter, preferably to at least part of the outer surface of the catheter.

In some embodiments, a further lubrication step is not performed. In such embodiments, the catheter may be used directly after step (b). Treating the catheter with the medium comprising the chlorine-based species of the invention provides both catheter sterilisation and lubrication and allows for optimal catheter lubrication even in the absence of a further lubrication step.

According to a third aspect of the invention, there is provided the use of a medium comprising at least one species independently selected from the group consisting of: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof, to sterilise and/or lubricate a reusable urinary catheter between uses.

The medium may preferably be the medium of the first aspect of the invention. The catheter may preferably be the catheter of the first aspect of the invention.

Statements of invention above relating to the first and second aspects of the invention may also be applied muwtis inutwidis to the third aspect of the invention.

In some embodiments, the medium containing the chlorine-based species of the invention may be used to sterilise the catheter. In such embodiments, the medium may also at least partially lubricate the catheter.

IS In some embodiments, the medium may both sterilise and lubricate the reusable urinary catheter. In such embodiments, the catheter may be used immediately after treatment with the medium. In such embodiments, a further pre-use lubrication step may not be required.

Detailed Description of the Invention

In order that the invention may be more clearly understood, embodiments thereof will now be described, by way of example only.

Reusable urinary catheter kit Reusable urinary catheter kits were provided. The kits comprised a container in the form of a tube comprising a flexible central portion and two rigid side portions. The tube contained an intermittent urinary catheter comprising a hollow polymeric tubular body comprising a base polymer formed from a thermoplastic el asto merle material and further comprising an amphiphilic additive. The container was tilled with a medium comprising one or more of: sodium hypochlorite, hypochlorous acid and chlorine dioxide, in which the intermittent catheter was submerged. An end of the container comprised a lid which was releasably attached to the container and allowed for the container to be opened and closed allowing for the catheter to be removed for use and re-inserted for storage between uses.

The catheter could simply be removed from the container and used in the conventional manner, without any requirement to rinse the catheter after removal from the medium and before use. Catheter lubricity was excellent even after long periods of time (up to 24 hours) and even without medium replacement. The media further provided excellent antimicrobial performance and overall catheter sterility. These variables were evaluated through the laboratory tests described below.

Example 1 -catheter lubrication using sodium hypochlorite and sodium chloride solution (no solution replenishment) At room temperature, water was added to an empty catheter storage container. A tablet comprising sodium hypochlorite and sodium chloride was thereafter dissolved in the water to provide a medium of the invention containing sodium hypochlorite and sodium chloride.

Catheters, as described in Example 1 above, were submerged in an aqueous solution comprising sodium hypochlorite and sodium chloride. The catheters were left submerged in the solution for different periods of time (2, 4, 6, 8, and 24 hours) before their lubricity was tested by determination of their coefficient of friction (COF).

One sample set was tested immediately after removal from the aqueous solution. The second sample set included a rinse step with water to remove residual aqueous solution prior to catheter COF testing. A control set was also included where the catheter was submerged in pure water instead of the aqueous solution.

A sample size of n=10 was applied to each sample set. Combined COF data was I 0 generated for all timepoints.

COF values for catheters submerged in the sodium hypochlorite/sodium chloride solution were low and well within acceptable ranges for intermittent catheters with lubricating coatings. Further, the results showed that storage in the sodium hypochlorite/soclium chloride solution with no rinse step following removal provides the optimal catheter IS lubricity.

Example 2 -catheter sterilisation using sodium hypochlorite and sodium chloride solution To assess the sterilisation potential of the medium of the invention, a microbiology assessment was conducted which consisted of rate of kill assessments against repeat inoculation of E. coli and E. lizecalis. These organisms were selected as they are commonly identified in catheter associated urinary tract infections. The selection also covers both gram-positive and gram-negative species to test the broad spectrum antimicrobial performance of the medium of the invention.

1 nterm ittent urinary catheters, as used for Example I, were provided and submerged in an aqueous medium comprising sodium hypochlorite and sodium chloride. The media comprising the catheters were respectively inoculated with the two microorganisms.

A direct inoculation method was applied against each microorganism. The test organisms were reinoculated following 1, 2, 3.4, 5, 6, and 24 hours. Following each inoculation, a sample was taken after 5 seconds, 1, 5, 10 and 15 minutes to evaluate the rate of kill.

Rapid kill against E. coil and E. faecalis was observed up to 3 and 2 hours respectively. In the case of E. coil considerable efficacy was also observed after 15 minutes of inoculation for samples taken up to 6 hours after initial submersion of the catheter in the inventive medium.

Overall, the results demonstrated excellent antimicrobial activity and sterilisation potential of the medium of the invention. Further, results show that the medium still provides significant antimicrobial activity even up to several hours after initial contact of the catheter with the medium.

Example 3 -catheter lubrication using sodium hypochlorite and sodium chloride solution (solution replenishment) Based upon the microbial assessment results, the lubricity assessment of Example 1 was repeated, but where the medium of the invention was disposed after each COF test and replenished with fresh medium, to mimic medium replacement after each catheter use. As 20 for Example 1, catheters were stored in the medium between COF tests.

Analogous tests were performed as for Example 1.

COP values for catheters submerged in the sodium hypochlorite/sodium chloride solution were once again well within acceptable ranges for intermittent catheters with lubricating coatings. Further, much less data point variation was observed that for Example 1. These results combined with that obtained from Example 2 demonstrate that replenishing the medium of the invention is optimal with respect to both the effectiveness of catheter sterilisation and the lubricity of the catheter.

Once again, the results show that storage in the sodium hypochlorite/sodium chloride solution with no rinse step following removal provides for optimal catheter lubricity.

Example 4 -catheter lubrication using hypochlorous acid Lubricity assessments analogous to those of Example 1 were performed -however, an aqueous hypochlorous acid solution was used as the medium of the invention in which the catheter was submerged between COP tests.

Similar results were observed as for Example 1, with COP values being achieved which were well within acceptable ranges for intermittent catheters with lubricating coatings.

Overall, performance in these tests demonstrated the lubricity enhancing effect of the hypochlorous acid containing medium of the invention, which was effective even after long time periods and without needing to replenish the medium between runs.

Example 5 -catheter lubrication using chlorine dioxide Lubricity assessments analogous to those of Example 4 were performed -however, an 20 aqueous chlorine dioxide solution was used as the medium of the invention in which the catheter was submerged between COF tests.

Similar results were observed as for Example 4.

Overall, performance in these tests demonstrated the lubricity enhancing of the chlorine dioxide containing medium of the invention, which was similarly effective even after long time periods and without a need to replenish medium between runs.

Example 6 -catheter sterilisation using hypochlorous acid A microbiology assessment was peiformed using a medium of the invention comprising hypochlorous acid in an analogous manner to that performed for Example 2. However, for this test, following each inoculation, a sample was only taken after 5 seconds to evaluate the rate of kill. Further, in addition to the previous microorganisms tested, a further gram-positive organism, S. aureas, was tested.

The results demonstrated excellent antimicrobial activity, with rapid kill being observed within just 5 seconds following inoculation against S. attretts and E. faecalis for up to 6 hours and for up to 24 hours against E. coll.

To evaluate the antimicrobial activity further, the test was repeated using the same frequency of inoculation, but with sampling performed up to 5 minutes after reinoculation at 24 hours. Even for the most challenging organism, E. .faecalis, a reduction in the microbial colony forming unit (CFU) counts of over 3 orders of magnitude was observed after 5 minutes of inoculation.

Overall, the results demonstrated excellent antimicrobial activity and sterilisation potential of the hypochlorous acid medium of the invention.

Example 7 -catheter sterilisation using chlorine dioxide A microbiology assessment was performed using a medium of the invention comprising chlorine dioxide in an analogous manner to that performed for Example 6.

The results demonstrated excellent antimicrobial activity, with rapid kill again being observed within just 5 seconds following inoculation against S. mums and E..faecalis for up to 6 hours and for up to 24 hours against E. coli.

To evaluate the antimicrobial activity further, the test was repeated using the same frequency of inoculation, but with sampling performed up to 5 minutes after rcinoculation at 24 hours. For the most challenging organism, E..faecalis, a reduction in the microbial colony forming unit (CFU) counts of 4 orders of magnitude was observed after around just 30 seconds of inoculation.

Overall, the results demonstrated excellent antimicrobial activity and sterilisation potential of the chlorine dioxide medium of the invention.

Example 8 -Effect of hypochlorous acid concentration on sterilisation potential The effect of the concentration of hypochlorous acid in the medium of the invention on sterilisation potential was tested. Aqueous media vv thhypochlorous acid concentrations of 250, 675, 1000, and 2000 ppm were supplied.

A microbiology assessment was performed using the media of the invention comprising hypochlorous acid in an analogous manner to that performed for Example 2. However, for this test, following each inoculation, samples were taken after 5 seconds, 30 seconds, 1,2, and 5 minutes to evaluate the rate of kill.

Effective kill was found up to 24 hours after 5 minutes of sampling for each concentration of hypochlorous acid tested and for both challenging organisms tested, E. coli and E. faecalis.

Effective kill was also observed up to 24 hours for both organisms 30 seconds after sampling for a hypochlorous acid concentration of just 675 ppm.

For E. coli, highly effective kill was observed up to 5 hours for all time periods post-inoculation when using only a 250 ppm hypochlorous acid solution. For concentrations of 675 ppm and above, highly effective kill was observed up to 24 hours for all time periods post-inoculation.

For the more challenging organism, E. faecalts, highly effective kill was observed up to 4 hours for all time periods post-inoculation when using only a 250 ppm hypochlorous acid solution. Up to 5 hours, highly effective kill was observed just 30 seconds post-inoculation using the 250 ppm solution. At 675 ppm, highly effective kill was observed up to 6 hours for all time periods post-inoculation, and up to 24 hours from just 30 seconds post-inoculation. At 1000 ppm, highly effective kill was observed up to 24 hours for all time periods post-inoculation.

Overall, the results demonstrate that whilst antimicrobial activities of the inventive media show dependence on the active ingredient concentration, excellent performance is shown at even very low concentrations and after long periods of time.

Conclusions

Overall, the above tests have shown that the media of the invention facilitate simple and highly effective catheter cleaning methods. Both highly effective lubrication and sterilisation can be achieved in the same step.

Lubrication and sterilisation can be achieved by as simply as contacting the catheter with the medium, such as by submerging the catheter in the medium. The medium also provides for long-term sterilisation and/or lubrication, allowing the catheter to be reused safely for relatively long time periods, without the need for overly frequent re-sterilisation and/or re-lubrication and without the need to replace the medium too frequently.

The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS1. A reusable urinary catheter kit. comprising a container comprising: a urinary catheter; and a medium comprising at least one species independently chosen from: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof.
2. A reusable urinary catheter kit as claimed in claim 1, wherein the catheter is an intermittent catheter.
3. A reusable urinary catheter kit. as claimed in any preceding claim, wherein the catheter further comprises at least one additive, preferably at least one amphiphilic additive.
4. A reusable urinary catheter kit as claimed in claim 3, wherein the amphiphilic additive is polymeric or oligomeric.
5. A reusable urinary catheter kit as claimed in claim 3 or 4 wherein the amphiphilic additive is an amphiphilic A-B block copolymer comprising a hydrophobic hydrocarbon A-block and a hydrophilic B-block.
6. A reusable urinary catheter kit as claimed in claim 5, wherein the amphiphilic additive is an A-B block copolymer comprising an A-block comprising a hydrocarbon chain block of the formula C1I3CH2(CH2CH2),, where "a" is 5-25 and preferably 9-25, and a hydrophilic B-block
7. A reusable urinary catheter kit as claimed in claim 5 or 6, wherein the B-block is a hydrophilic oligomer comprising between 2 and 10 monomer units optionally derived from monomers selected from the group consisting of: alkylene oxides, alkylene glycols, epihalohydrins, unsaturated carboxylic acids, alkylene imines, lactones, vinyl alcohol, and vinyl alkanoates.
8. A reusable urinary catheter kit as claimed in any preceding claim, wherein the catheter comprises a hollow polymeric tubular body comprising a base polymer that is independently selected from the group consisting of polyolefins, polyesters, polyacrylates, polyamides, thermoplastic elastomeric material, polyether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, fluororubber, water disintegrable or enzymatically hydrolysable material, and combinations, blends or copolymers of any of the above materials.
9. A reusable urinary catheter kit as claimed in claim 8, wherein the base polymer comprises a polymer independently selected from the group consisting of: polyolefins, polyvinyl chloride, polyurethane, styrene-butadiene copolymer (SBC), styrene-ethylene-butylene-styrene copolymer (SEBS), thermoplastic elastomeric material, and combinations, blends or copolymers of any of the above materials.
10. A reusable urinary catheter kit. as claimed in any preceding claim, wherein the medium comprises hypochlorous acid and/or the at least one hypochloiite salt in a total combined concentration of between 0.005-0.6 wt.% of the medium.
11. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium further comprises sodium chloride.
12. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium further comprises at least one base, preferably comprising sodium hydroxide.
13. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium comprises molecular chlorine.
14. A reusable urinary catheter kit. as claimed in any preceding claim, wherein the medium is present as a solution, preferably an aqueous solution.
15. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium is present as a liquid having a viscosity of between 0.5-5000 cP.
16. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium has a pH of between 2 and 14.
17. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium is in direct contact with the catheter, preferably with at least one surface thereof.IS
18. A reusable urinary catheter kit as claimed in claim 17, wherein the catheter is submerged in the medium.
19. A reusable urinary catheter kit as claimed in any preceding claim, wherein the medium is contained in a separate container that is located in the container and is not in direct contact with the catheter.
20. A reusable urinary catheter kit as claimed in claim 19, wherein the separate container is pierceable, in use, to release the contained medium from the separate container and into direct contact with the catheter.
21. A method of steril king and/or lubricating a reusable urinary catheter, the method comprising the steps of: a. Providing a reusable urinary catheter; and b. Treating the reusable urinary catheter with a medium comprising at least one species independently chosen from: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof.
22. A method as claimed in claim 21, wherein step (b) comprises treating at least one surface of the catheter with the medium, preferably at least an outer surface of the catheter.
23. A method as claimed in claim 21 or 22, wherein step (b) comprises submerging the catheter in the medium.
24. A method as claimed in any one of claims 21 to 23, wherein the method is performed before and/or after each use of the catheter.
25. Use of a medium comprising at least one species independently chosen from: hypochlorous acid, at least one hypochlorite salt, chlorine dioxide, and combinations thereof, to sterilise and/or lubricate a reusable urinary catheter between uses.