Vaginal lubricant

Abstract

An aqueous lubricant having a pH of 4.5 or less and an osmolality by weight of 500 mOsm / kg or less wherein the lubricant comprises: a copolymer comprising an acrylamide and a monomer having a carboxylic acid group or a carboxylic ester group; and a thickening agent, wherein the thickening agent is alkyl cellulose, hydroxyalkyl cellulose or carboxyalkyl cellulose. The invention also provides a product containing the lubricant and a method for preparing the lubricant. The use of the aqueous lubricant in providing lubrication and / or moisturizing to the skin or mucous membranes of a subject, preferably to the vagina and / or during sexual activity. The method for preparing the aqueous lubricant comprises dispersing the thickener in water, and adding the copolymer in a subsequent step using a mixing at less than 1000 rpm; preferably, the method comprises the step of dispersing the thickening agent in the water at the speed of 1000 rpm or above.

Description

TECHNICAL FIELD

[0001] The present invention is in the field of personal lubricants. In particular, the present invention relates to a lubricant, a product comprising the lubricant, the use of the lubricant and a method of making it. BACKGROUND

[0002] Due to hormonal changes accompanying the menstrual cycle, women of childbearing age will naturally be drier, or at least not optimally lubricated, in the vaginal area for most of each month. Many other factors also affect the level of natural lubrication at different ages, including stress or anxiety, pregnancy, breastfeeding, hormonal contraceptive pills, diabetes, some cancer treatments and douching. Vaginal dryness or poor lubrication can cause discomfort during sexual activity and ultimately a reluctance to engage in sexual activity.

[0003] Personal lubricants are a specialised class of lubricants used to reduce friction with body tissues during sexual activity. They can also be described as personal moisturisers, as they can be used at other times to reduce discomfort associated with vaginal dryness. The technical considerations for a standalone lubricant / moisturiser tend to be different from, for example, the type of lubricant pre-provisioned on the surface of a condom. The latter must be stably stored with the condom material and its packaging for years. The present invention is primarily focused on a standalone product designed to be applied directly to the vagina, whether to enhance sexual activity or for additional lubrication or moisturisation outside of sexual activity. Of course, the consumer can still choose to apply the product to the penis, other intimate areas, a condom or a sex toy.

[0004] There is a wide variety of standalone personal lubricants currently available. They can be water-based or water-free (typically silicone-based), depending on the intended area of application and the required condom or toy compatibility. Silicone-based lubricants damage sex toys made from silicone and can soil fabrics, but tend to be more long-lasting; water-based personal lubricants are the most widely used type on the global market.

[0005] Historically, water-based personal lubricants have tended to have a weight molar osmolality in the range of 200 to 300 mOsm / kg, which is much higher than the typical vaginal osmolarity. It is now recognised that the weight osmolality of a lubricant is important, as the epithelial cells of the vaginal lining will continually attempt and maintain homeostasis. Hyperosmolar lubricants cause the vaginal cells to release liquid to dilute the lubricant. This can cause epithelial cell damage, which in turn leads to an increased risk of infection due to a compromised epithelial barrier. The vagina can also become drier. This is particularly problematic for postmenopausal women, as the use of hyperosmolar lubricants exacerbates vaginal dryness.

[0006] On the other hand, hypo-osmolar lubricants (which are quite rare on the market) cause vaginal cells to draw water from the lubricant. In extreme cases, this can cause the cells to swell and eventually rupture. The ideal lubricant is iso-osmolar. However, formulating personal lubricants within this range is not simple, while also balancing the need to achieve many other parameters, including the desired viscosity, glide properties, and rheological stability during storage. In 2012, the World Health Organization (WHO) in its Consultation Note WHO / UNFPA / FHI360 recommended that health care organizations procure personal lubricants with an osmolality below 1200 mOsm / kg.

[0007] It is now also recognized that controlling the pH of water-based lubricants is important. The pH of a healthy vagina is typically in the range of 3.8-4.5; a high pH increases the risk of bacterial vaginosis. The WHO Consultation Note states that ideally the pH of a vaginal lubricant should be about 4.5, but procurement agencies should procure lubricants with a pH of 7 or below. This recommendation takes into account the possibility of cross-use, where a vaginal lubricant can be used rectally, and ideal rectal lubricants have a pH of about 5.5 to 7.

[0008] WO2022 / 153066 discloses lubricants with reduced high osmolality and a relatively low pH. Recently, some vaginal lubricants have also appeared on the market that have a pH and osmolality close to the natural environment of the vagina. However, these do not have the physical texture of simulating natural vaginal fluid. Consumers can describe them as watery and / or unnatural feeling.

[0009] US3, 965, 908 discloses a “synthetic physiological mucus” that can be used as a vaginal lubricant, which has physical properties similar to natural mucus. It is based on a mucilaginous aqueous solution of high molecular weight anionic polyacrylamide, preferably with 26% to 36% of the amide groups substituted with carboxyl groups. Although the polymer is said to be stable in a pH range of about 3-10, the document teaches that the desired mucus-like properties can only be maintained in a pH range of about 5-8. EP0014238A2 has a similar disclosure; although it states that the pH can vary in the range of 3.0-10.0 without changing the texture and physiological properties, it suggests that a pH of about 5.0 should be used for the vaginal area. The specific example formulations in these documents contain only polyacrylamide, a preservative, citric acid, and water; although the osmolality is not mentioned, it is predicted that they have a significantly low osmolality.

[0010] It would be advantageous to formulate a water-based vaginal lubricant that has a texture similar to natural vaginal fluid, while still being pH-friendly and more iso-osmolar to the vagina. SUMMARY

[0011] In a first aspect of the application, there is provided a lubricant as claimed in claim 1.

[0012] In a second aspect of the application, there is provided a product comprising a lubricant according to the first aspect of the application, the lubricant being provided within a bottle or sachet and packaged separately from any condom present in the product.

[0013] In a third aspect of the application, there is provided the use of a lubricant according to the first aspect of the application for providing lubrication and / or moisturisation to the skin or mucosa of a subject.

[0014] In a fourth aspect of the application, there is provided a method of making a lubricant according to the first aspect of the application, comprising dispersing a thickening agent in water and adding a copolymer in a subsequent step using mixing at less than 1000 rpm. DETAILED DESCRIPTION

[0015] Embodiments described herein in relation to one aspect of the application can be combined with each other and can equally apply to other aspects of the application, unless stated to the contrary or required by context.

[0016] The lubricant of the application comprises a copolymer of acrylamide and a monomer having a carboxylic acid group or a carboxylate group. Preferably, the copolymer is: a copolymer of acrylamide and a monomer having an acrylic acid group, preferably a copolymer of acrylamide and (alkyl)acrylic acid, preferably a copolymer of acrylamide and (C1-3 alkyl)acrylic acid, preferably a copolymer of acrylamide and acrylic acid / methacrylic acid, preferably a copolymer of acrylamide and acrylic acid; or a salt of any of the foregoing. The copolymer can comprise more than two monomers, but preferably the additional monomer is also (alkyl)acrylic acid or a salt thereof, for example the copolymer can be a terpolymer of acrylamide, an acrylic acid ester or salt and a methacrylic acid ester or salt (or the acid form thereof). Preferably, it is a copolymer of only two monomers. In one embodiment, the copolymer comprises at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70% or at least 75% and / or at most 90%, at most 85%, at most 80%, at most 75%, at most 70%, at most 65%, at most 60%, at most 55% or at most 50% molar % of acrylamide groups. In one embodiment, the copolymer comprises 10% to 90%, 40% to 85% or 60% to 75% molar % of acrylamide groups.

[0017] Preferably, the copolymer is provided in salt form, preferably an alkali metal salt, preferably a sodium or potassium salt, preferably a sodium salt. For example, the copolymer can be a copolymer of acrylamide and sodium acrylate. Preferably, the raw material comprising the copolymer for making the lubricant comprises a very low residual content of acrylamide monomer, preferably no more than 0.05 wt%, no more than 0.04 wt%, no more than 0.03 wt% or no more than 0.02 wt%.

[0018] In one embodiment, the copolymer has a weight average molecular weight of: at least 1,000,000 Da, at least 1,500,000 Da, at least 2,000,000 Da, at least 2,500,000 Da, at least 3,000,000 Da, at least 3,500,000 Da, at least 4,000,000 Da, at least 4,500,000 Da or at least 5,000,000 Da; and / or at most 10,000,000 Da, at most 9,000,000 Da, at most 8,000,000 Da, at most 7,000,000 Da, at most 6,000,000 Da or at most 5,000,000 Da. In one embodiment, the copolymer has a weight average molecular weight of 1,000,000 to 10,000,000 Da, preferably 2,000,000 to 6,000,000 Da, preferably 3,000,000 to 5,000,000 Da.

[0019] Suitable polyacrylamide copolymers can be manufactured according to known synthesis methods or obtained commercially, for example, Praestol® series, such as Praestol LT27 AP AG, available from Solenis. TM

[0020] ​Preferably, the lubricant comprises the copolymer in an amount of at least 0.01 wt%, at least 0.02 wt%, at least 0.03 wt%, at least 0.04 wt%, at least 0.05 wt%, at least 0.06 wt%, at least 0.07 wt%, at least 0.08 wt%, at least 0.09 wt%, at least 0.1 wt%, at least 0.15 wt%, or at least 0.2 wt%; and / or at most 0.5 wt%, at most 0.45 wt%, at most 0.4 wt%, at most 0.35 wt%, at most 0.3 wt%, at most 0.25 wt%, at most 0.20 wt%, at most 0.15 wt%, or at most 0.10 wt%. In one embodiment, the lubricant comprises the copolymer in an amount of 0.01 wt% to 0.5 wt%, 0.1 wt% to 0.4 wt%, 0.15 wt% to 0.25 wt%, 0.2 wt%, or about 0.2 wt%. In one embodiment, the lubricant comprises the copolymer in an amount of 0.05 wt% to 0.15 wt%, 0.06 wt% to 0.10 wt%, 0.07 wt% to 0.09 wt%, 0.08 wt%, or about 0.08 wt%.

[0021] The present inventors have found that in the lubricants of the present application, the polyacrylamide copolymer can not be an effective thickener in the lower pH range. In order to increase the viscosity of the formulation, while maintaining a thick, slimy-like texture, a carefully selected thickener is used in combination with the copolymer. The thickener is an alkyl cellulose (e.g. methyl cellulose), a hydroxyalkyl cellulose, or a carboxyalkyl cellulose (e.g. carboxymethyl cellulose). In one embodiment, the lubricant comprises more than one such thickener. In one embodiment, the lubricant comprises another thickener different from such a thickener, but preferably it does not comprise a thickener other than an alkyl cellulose, a hydroxyalkyl cellulose, and / or a carboxyalkyl cellulose (in addition to the polyacrylamide copolymer which can itself contribute to thickening).

[0022] The thickener is preferably one which allows the preparation of a transparent gel with good flow properties. It should also be able to thicken the lubricant in the target pH range of the lubricant. In the development process, the present inventors tested xanthan gum, and found that this adversely affected the transparency and could not give a product with smooth flow. Another known thickener, Aristoflex AVC, did not thicken well in a low pH environment.

[0023] In one embodiment, the thickener used in the present application is a hydroxyalkyl cellulose, such as a hydroxymethyl cellulose or a hydroxyethyl cellulose, preferably a hydroxyethyl cellulose.

[0024] Preferably, the lubricant comprises a thickening agent in an amount of at least 0.2 wt%, at least 0.3 wt%, at least 0.4 wt%, at least 0.5 wt%, or at least 0.6 wt%, at least 0.7 wt%, or at least 0.8 wt%; and / or at most 1.0 wt%, at most 0.9 wt%, at most 0.8 wt% or at most 0.7 wt%. In one embodiment, the lubricant comprises a thickening agent in an amount of 0.2 wt% to 1.0 wt%, preferably 0.4 wt% to 0.9 wt% or 0.4 wt% to 0.8 wt%, preferably 0.6 wt% to 0.9 wt%, 0.6 wt% to 0.7 wt%, 0.7 wt% to 0.8 wt%, about 0.6 wt% or about 0.8 wt%. Preferably, the total amount of thickening agent (excluding the amount of copolymer which itself acts as a thickening agent) is within the foregoing ranges.

[0025] In one embodiment, the lubricant comprises a humectant. Many polyol compounds act as humectants, in particular diols and triols such as glycerol. However, the use of glycerol is less preferred. There are some suggestions in the field that glycerol can act as a food source for Candida albicans, a yeast associated with vaginal candidiasis. The WHO advisory suggests using a total glycol content of less than about 8.3 wt% to limit the osmolality. However, the present inventors have recognised that the specific choice of diol can also affect properties. Polymeric diols such as polyalkylene glycols impart a lower osmolality, but can result in a more viscous perceived product. On the other hand, 1,3-propane diol can also impart a viscous texture.

[0026] In one embodiment, the lubricant comprises a monomeric diol, preferably a diol having 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms, preferably a diol having 3 to 5 carbon atoms, preferably 3 or 4 carbon atoms, preferably 3 carbon atoms. Preferably, the lubricant comprises propylene glycol (1,2-propane diol).

[0027] In one embodiment, the lubricant is free or substantially free of glycerol and / or 1, 3-propane diol and / or polymeric diols. In one embodiment, it contains less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, less than 0.05 wt% or less than 0.01 wt% of any or each of glycerol, 1, 3-propane diol or polymeric diols.

[0028] Preferably, the lubricant comprises propylene glycol in an amount of at least 0.5 wt%, at least 0.6 wt%, at least 0.7 wt%, at least 0.8 wt%, at least 0.9 wt%, at least 1.0 wt%, at least 1.1 wt%, at least 1.2 wt%, at least 1.3 wt%, at least 1.4 wt%, at least 1.6 wt%, at least 1.7 wt%, at least 1.8 wt%, at least 1.9 wt%, or at least 2.0 wt%; and / or at most 4.0 wt%, at most 3.9 wt%, at most 3.8 wt%, at most 3.7 wt%, at most 3.6 wt%, at most 3.5 wt%, at most 3.4 wt%, at most 3.3 wt%, at most 3.2 wt%, at most 3.1 wt%, at most 3.0 wt%, at most 2.9 wt%, at most 2.8 wt%, at most 2.7 wt%, at most 2.6 wt%, at most 2.5 wt%, at most 2.4 wt%, at most 2.3 wt%, at most 2.2 wt%, at most 2.1 wt%, or at most 2.0 wt%. In one embodiment, the lubricant comprises propylene glycol in an amount of 0.5 wt% to 4.0 wt%, preferably 1.0 wt% to 3.0 wt%, preferably 1.5 wt% to 2.5 wt%, preferably 2.0 wt%, or about 2 wt%. In one embodiment, the total amount of diols (or polyols) is within the same ranges. In one embodiment, the only polyol present is a diol. In one embodiment, the propylene glycol is the only polyol present.

[0029] In one embodiment, the pH of the lubricant of the present application is at least 3.0, at least 3.1, at least 3.2, at least 3.3, at least 3.4, at least 3.5, at least 3.6, at least 3.7, or at least 3.8; and / or at most 4.5, at most 4.4, at most 4.3, at most 4.2, at most 4.1, at most 4.0, at most 3.9, or at most 3.8. In one embodiment, it has a pH of 3.0-4.5, 3.2-4.5, 3.5-4.5, 3.5-4.4, 3.8-4.3, 3.8, or about 3.8. In particular, these pH values can be measured at 25°C.

[0030] Any suitable pH adjusting agent in an appropriate amount can be used to achieve the desired pH. For example, an organic acid such as lactic acid or citric acid can be used. Lactic acid is preferred because it is naturally present in the healthy vagina as a metabolic product of Lactobacillus species that are present in the healthy vagina. Vaginal lactic acid has been shown to have benefits including enhancing epithelial cell function and immune modulation. Preferably, the lubricant contains a pH buffer, for example an organic acid in combination with a corresponding salt. In one embodiment, this is provided by a combination of lactic acid and a lactate salt such as potassium lactate.

[0031] Normal female vaginal secretions have an osmolality of 260 mOsm / kg to 290 mOsm / kg. The lubricant of the present application has an osmolality of 500 mOsm / kg or less, and preferably has an osmolality of at most 490 mOsm / kg, at most 480 mOsm / kg, at most 470 mOsm / kg, at most 460 mOsm / kg, at most 450 mOsm / kg, at most 440 mOsm / kg, at most 430 mOsm / kg, at most 410 mOsm / kg, at most 400 mOsm / kg, at most 390 mOsm / kg, or at most 380 mOsm / kg; and / or at least 100 mOsm / kg, at least 110 mOsm / kg, at least 120 mOsm / kg, at least 130 mOsm / kg, at least 140 mOsm / kg, at least 150 mOsm / kg, at least 160 mOsm / kg, at least 170 mOsm / kg, at least 180 mOsm / kg, at least 190 mOsm / kg, at least 200 mOsm / kg, at least 210 mOsm / kg, at least 230 mOsm / kg, at least 240 mOsm / kg, at least 250 mOsm / kg, or at least 260 mOsm / kg. In one embodiment, the lubricant has an osmolality of 100 mOsm / kg to 500 mOsm / kg, 200 mOsm / kg to 500 mOsm / kg, 200 mOsm / kg to 400 mOsm / kg, 250 mOsm / kg to 400 mOsm / kg, or 260 mOsm / kg to 380 mOsm / kg.

[0032] Any suitable preservative can be used in the formulation. Preferably, the formulation is substantially free of parabens. Preferably, it is free of parabens. Studies have raised health concerns associated with parabens, for example relating to effects on hormone regulation and breast cancer risk. The preservative used in the present application can optionally be an acid having a pKa in the range 2-5. The preferred preservative in the present application is benzoic acid, which has a pKa of 4.2.

[0033] In one embodiment, the lubricant comprises water in an amount of at least 80 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 96 wt%.

[0034] Preferably, the lubricant is transparent and / or colourless. However, if desired, a suitable dye or colouring agent can be added in a suitable amount, as known to the person skilled in the art.

[0035] Preferably, the lubricant has a viscosity (as measured by a Brookfield viscometer) of: at least 200 cP, at least 250 cP, at least 300 cP, at least 350 cP, at least 380 cP, or at least 400 cP; and / or at most 1500 cP, at most 1400 cP, at most 1300 cP, at most 1200 cP, at most 1100 cP, at most 1000 cP, at most 900 cP, or at most 800 cP. In one embodiment, the lubricant has a viscosity of 200 cP to 1500 cP, 300 cP to 1000 cP, or 400 cP to 800 cP. Preferably, these viscosities are measured by a Brookfield viscometer using spindle RV3 at 50 rpm and 25 °C.

[0036] Another aspect of the application is a product comprising the lubricant of the application, provided in a bottle or sachet, and packaged separately from any condom present in the product. For example, the bottle can be a container with a simple spout or pump dispenser. The product can be a kit comprising a sachet of lubricant and a separately packaged condom, for example where the sachet contains a small sample of lubricant for trial purposes.

[0037] Another aspect of the application is the use of the lubricant of the application for providing lubrication and / or moisturisation to the skin or mucosa of a subject. Preferably, the lubricant provides lubrication and / or moisturisation to the vagina or other intimate area. Preferably, the lubricant is used during sexual activity. The user can apply the lubricant directly to the vagina or other intimate area, or to a condom. In one embodiment, the lubricant is used to relieve vaginal dryness.

[0038] The lubricant can be manufactured using standard techniques known to those skilled in the art. Preferably, once the polyacrylamide copolymer is added, high shear mixing (greater than 1000 rpm) is avoided in order to maintain the desired stringy texture. However, high shear mixing can be desirable prior to the addition of the polyacrylamide copolymer in order to disperse other ingredients (e.g. thickening agents) at lower temperatures. For example, the method of manufacture can comprise dispersing the hydroxyethyl cellulose in water using a high shear homogeniser, and subsequently adding the polyacrylamide copolymer under low shear mixing. Preferably, the entire manufacturing process is carried out at a temperature of no more than 40 °C, no more than 35 °C, or no more than 30 °C.

[0039] Another aspect of the application relates to a method of manufacturing the lubricant of the application. The method of the application can have the advantage of a shorter manufacturing time and / or lower energy consumption.

[0040] Examples

[0041] The following non-limiting examples are intended to illustrate the application.

[0042] Example 1

[0043]

[0044] The formulations of the present application of these examples were prepared by dispersing the hydroxyethyl cellulose in water with a homogenizer until uniform, then slowly and gently adding the polyacrylamide copolymer with an overhead stirrer until fully swollen and no lumps were observed. The remaining ingredients were added with continued gentle stirring. No heating was applied during this process. CLAIM (MODIFIED PURSUANT TO ARTICLE 19 OF THE TREATY) 1. An aqueous personal lubricant having a pH of 4.5 or less and an osmolality of 500 mOsm / kg or less, wherein the lubricant comprises: a copolymer comprising acrylamide and a monomer having a carboxylic acid group or carboxylate group; and a thickening agent which is an alkyl cellulose, a hydroxyalkyl cellulose, or a carboxyalkyl cellulose. 2. The aqueous lubricant of claim 1, wherein the copolymer comprises acrylamide and an acrylate, preferably wherein the copolymer is a copolymer of acrylamide and sodium acrylate. 3. The aqueous lubricant of claim 1 or 2, wherein the thickening agent is a hydroxyalkyl cellulose, preferably hydroxyethyl cellulose. 4. The aqueous lubricant of any one of the preceding claims, comprising the thickening agent in an amount of at least 0.2 wt%, at least 0.3 wt%, at least 0.4 wt%, at least 0.5 wt%, at least 0.6 wt%, at least 0.7 wt%, or at least 0.8 wt%; and / or at most 1.0 wt%, at most 0.9 wt%, at most 0.8 wt%, or at most 0.7 wt%. 5. The aqueous lubricant of any one of the preceding claims, comprising the copolymer in an amount of at least 0.01 wt%, at least 0.02 wt%, at least 0.03 wt%, at least 0.04 wt%, at least 0.05 wt%, at least 0.06 wt%, at least 0.07 wt%, at least 0.08 wt%, at least 0.09 wt%, at least 0.1 wt%, at least 0.15 wt%, or at least 0.2 wt%; and / or at most 0.5 wt%, at most 0.45 wt%, at most 0.4 wt%, at most 0.35 wt%, at most 0.3 wt%, at most 0.25 wt%, at most 0.20 wt%, at most 0.15 wt%, or at most 0.10 wt%. 6. The aqueous lubricant of any one of the preceding claims, comprising a monomeric diol, preferably a diol having 3 to 5 carbon atoms, preferably propylene glycol. 7. The aqueous lubricant of any one of the preceding claims, wherein the total amount of polyol in the lubricant is 0.5 to 4.0 wt%, preferably propylene glycol is the only polyol in the lubricant. 8. The aqueous lubricant of any one of the preceding claims having an osmolality of 200 to 500 mOsm / kg, preferably 250 to 400 mOsm / kg, preferably 260 to 380 mOsm / kg. 9. The aqueous lubricant of any one of the preceding claims having a pH of 3.2 to 4.5, preferably 3.5 to 4.4, preferably 3.8 to 4.3. 10. The aqueous lubricant of any one of the preceding claims having a viscosity of at least 200 cP, at least 250 cP, at least 300 cP, at least 350 cP, at least 380 cP or at least 400 cP; and / or at most 1500 cP, at most 1400 cP, at most 1300 cP, at most 1200 cP, at most 1100 cP, at most 1000 cP, at most 900 cP or at most 800 cP, as measured by a Brookfield viscometer. 11. A product comprising the aqueous lubricant of any one of the preceding claims, the aqueous lubricant being provided within a bottle or sachet and packaged separately from any condom present in the product. 12. Use of the aqueous lubricant of any one of claims 1 to 10 for providing lubrication and / or moisturisation to the skin or mucosa of a subject, preferably to the vagina and / or during sexual activity. 13. A method of making the aqueous lubricant of any one of claims 1 to 10, comprising dispersing the thickening agent in water and adding the copolymer in a subsequent step using mixing at less than 1000 rpm; preferably, it comprises dispersing the thickening agent in water using mixing at more than 1000 rpm. 14. The method of claim 13, wherein the temperature is kept at no more than 40°C throughout the method.

Claims

1. An aqueous lubricant having a pH of 4.5 or less and an osmolality of 500 mOsm / kg or less, wherein, The lubricant comprises: a copolymer comprising acrylamide and a monomer having a carboxylic acid group or carboxylate group; and a thickening agent which is an alkyl cellulose, a hydroxyalkyl cellulose, or a carboxyalkyl cellulose.

2. The aqueous lubricant of claim 1, wherein, The copolymer comprises acrylamide and an acrylate, preferably wherein the copolymer is a copolymer of acrylamide and sodium acrylate.

3. The aqueous lubricant of claim 1 or 2, wherein, The thickening agent is a hydroxyalkyl cellulose, preferably hydroxyethyl cellulose.

4. The aqueous lubricant of any one of the preceding claims, comprising the thickening agent in an amount of: at least 0.2 wt%, at least 0.3 wt%, at least 0.4 wt%, at least 0.5 wt%, at least 0.6 wt%, at least 0.7 wt%, or at least 0.8 wt%; and / or at most 1.0 wt%, at most 0.9 wt%, at most 0.8 wt%, or at most 0.7 wt%.

5. The aqueous lubricant of any one of the preceding claims, comprising the copolymer in an amount of: at least 0.01 wt%, at least 0.02 wt%, at least 0.03 wt%, at least 0.04 wt%, at least 0.05 wt%, at least 0.06 wt%, at least 0.07 wt%, at least 0.08 wt%, at least 0.09 wt%, at least 0.1 wt%, at least 0.15 wt%, or at least 0.2 wt%; and / or at most 0.5 wt%, at most 0.45 wt%, at most 0.4 wt%, at most 0.35 wt%, at most 0.3 wt%, at most 0.25 wt%, at most 0.20 wt%, at most 0.15 wt%, or at most 0.10 wt%.

6. The aqueous lubricant of any one of the preceding claims, comprising a monomeric diol, preferably a diol having 3 to 5 carbon atoms, preferably propylene glycol.

7. The aqueous lubricant of any one of the preceding claims, wherein, The total amount of polyol in the lubricant is 0.5 wt% to 4.0 wt%, preferably propylene glycol is the only polyol in the lubricant.

8. The aqueous lubricant of any one of the preceding claims, having an osmolality of 200 mOsm / kg to 500 mOsm / kg, preferably 250 mOsm / kg to 400 mOsm / kg, preferably 260 mOsm / kg to 380 mOsm / kg.

9. The aqueous lubricant of any one of the preceding claims, having a pH of 3.2 to 4.5, preferably 3.5 to 4.4, preferably 3.8 to 4.

3.

10. The aqueous lubricant of any one of the preceding claims, having a viscosity of at least 200 cP, at least 250 cP, at least 300 cP, at least 350 cP, at least 380 cP, or at least 400 cP; and / or at most 1500 cP, at most 1400 cP, at most 1300 cP, at most 1200 cP, at most 1100 cP, at most 1000 cP, at most 900 cP, or at most 800 cP, as measured by a Brookfield viscometer.

11. A product comprising the aqueous lubricant of any of the preceding claims, said aqueous lubricant being provided in a bottle or sachet and packaged separately from any condom present in the product.

12. Use of the aqueous lubricant of any of claims 1 to 10 for providing lubrication and / or moisturization to the skin or mucosa, preferably to the vagina, of a subject and / or during sexual activity.

13. A method of preparing the aqueous lubricant of any of claims 1 to 10, comprising dispersing the thickening agent in water and adding the copolymer in a subsequent step using mixing at less than 1000 rpm; preferably, it comprises dispersing the thickening agent in water using mixing at more than 1000 rpm.

14. The method of claim 13, wherein, Throughout the method, the temperature is kept at no more than 40°C.

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