Hyaluronic acid hydrogel formulation comprising phytoestrogen for the treatment of vaginal atrophy and vaginal rejuvenation and production method thereof

Abstract

The present invention relates to a hyaluronic acid hydrogel formulation comprising phytoestrogen for the treatment of vaginal atrophy and vaginal rejuvenation and production method thereof. The objective of the present invention is to obtain hyaluronic acid hydrogel comprising phytoestrogen, which are herbal substances that can produce estrogenic effects and have the same structure and functions as estradiol. In this way, risks such as heart attack, stroke and blood clotting seen in alternative hormone comprising treatment methods are not encountered.

Description

[0001] HYALURONIC ACID HYDROGEL FORMULATION COMPRISING PHYTOESTROGEN FOR THE TREATMENT OF VAGINAL ATROPHY AND VAGINAL REJUVENATION AND PRODUCTION METHOD

[0002] THEREOF

[0003] Field of the Invention

[0004] The present invention relates to a hyaluronic acid hydrogel formulation comprising phytoestrogen for the treatment of vaginal atrophy and vaginal rejuvenation, and production method thereof.

[0005] Background of the Invention

[0006] The corpus luteum of the ovary secretes large amounts of estrogen after maturation at puberty. Estrogen levels for young women vary with the menstrual cycle but are usually at high levels. But at the onset of menopause, the estrogen level in the body suddenly drops. This can lead to uncomfortable symptoms called menopause syndrome, such as hot flashes, night sweats, insomnia, mood swings, vaginal dryness, and vaginal atrophy.

[0007] Vaginal atrophy is the thinning of the vaginal mucosa in women due to estrogen deficiency. It causes a decrease in fibroblast activity in the connective tissue called lamina propria under the vaginal mucosa. It also causes a decrease in fibrils such as collagen and hyaluronic acid in the vaginal wall. Vaginal atrophy is most common during menopause. The inability to release estrogen from the ovaries due to menopause not only prevents menstruation, but also causes a deficiency of estrogen wherever it is effective in the body. When the vaginal mucosa begins to thin, problems such as frequently recurring vaginal infections, urinary problems and difficulty in sexual intercourse occur. Common symptoms of vaginal atrophy are as follows:

[0008] • Thinning of the vaginal mucosa

[0009] • Narrowing and shortening of the vaginal canal • Loss of moisture due to vaginal dryness

[0010] • Burning sensation in the vagina

[0011] • Spotting after intercourse

[0012] • Pain and difficulty in sexual intercourse

[0013] • Pain and burning sensation while urinating

[0014] • Frequent urinary tract infections

[0015] • Urinary incontinence

[0016] Although every woman experience atrophy in the vagina to a certain extent, this is known to be a major problem for 25% of menopausal women. Women who have never given birth or who have given birth by cesarean section experience more apparent problems than women who have had a normal birth. Women who have a regular sexual life experience less distress because of increased mucous blood flow. In addition, women who smoke may have vaginal dryness and experience more resistance to treatment.

[0017] Replacing what is missing is the basis of treatment in vaginal atrophy. For this reason, suppositories, gels or creams known as topical estrogens are used. These products also provide the necessary lubricity and moisture. In addition, the decrease in estrogen can be directly controlled with hormone replacement therapy (HRT). HRT is divided into two, namely systemic and topical administration [1, 2].

[0018] Systemic HRT is administered via pills or patches. Estrogen hormone is included in the blood circulation and provides relief of systemic symptoms. Studies have shown that systemic hormone therapy can increase the risk of heart attack, stroke, and blood clots. It has also been reported that long-term use may cause endometrial hyperplasia and increase the risk of cancer [3].

[0019] Topical HRT is usually preferred when only topical symptoms such as vaginal atrophy are experienced. Estrogen released during topical application can be directly absorbed by the vaginal mucosa. Due to the low dosage of topical HRT administration, estrogen hormone penetrates the body in lesser amounts than systemic estrogen therapy. This reduces the side effects and risks associated with systemic estrogen therapy [4].

[0020] Another method used in vaginal atrophy is PRP (platelet rich plasma). It is a good reservoir for many growth factors such as platelet-derived growth factor (PDGF), epidermal growth factor (EGF), transforming growth factor beta 1 (TGF-pi), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b- FGF), hepatocyte growth factor (HGF) and insulin-like growth factor (IGF-I). PRP is applied directly to the mucosa in the vagina, which activates the fibroblasts in the mucosa and provides the production of new collagen and elastin.

[0021] Another method used in vaginal atrophy is the use of fractional CO2 lasers. Fractional CO2 laser is applied to the inner wall of the vagina with a special apparatus. In this application, the laser is used in the vagina for the same purpose as for facial skin rejuvenation. After the application, the regeneration of the vaginal mucosa and the increase of support tissues such as new collagen in the vaginal wall are ensured. These improvements increase the moisture in the vagina and the rejuvenation of the vaginal wall enables narrowing.

[0022] When administering local and systemic estrogen preparations, it is necessary to carefully consider the side effects and risks of complications of drugs associated with systemic adsorption. Excessive estrogen levels in postmenopausal women can increase the risks of heart disease, breast cancer, thromboembolic complications, and cerebrovascular disease [5]. Low-dose local estrogens should be preferred, especially if the treatment is administered to elderly patients.

[0023] However, despite the large number of positive data showing improved vaginal health and sexual function with estrogens and moisturizers, recent data from Mitchell et al. are controversial as they both show no benefit when compared to placebo [6].

[0024] Some studies have reported that laser procedures have potential complications such as scarring, infection, pain, and decreased sexual desire. Another disadvantage of CO2 laser treatment is that it is a relatively new treatment and there has not been much study on a long-term clinical follow-up so far. In addition, the fact that it is an expensive treatment is another disadvantage [7].

[0025] Various agents are used in vaginal drug delivery systems, such as creams, gels, tablets, capsules, ointments, and the like. However, these substances have some limitations such as leaking, low retention time and daily dose requirement [8, 9]. Recently, many studies have been carried out on hydrogels to overcome these problems

[0010] .

[0026] Postmenopausal women using hormone replacement therapy (HRT) usually stop the treatment before they complete it. This may be due to the increased cancer risk of local estrogens, as well as breast swelling / tenderness, bleeding or spotting, and bloating, which are side effects associated with HRT

[0011] . As a result, the use of compounds comprising non-hormonal substances such as phytoestrogens is attracting more attention as safer alternatives

[0012] .

[0027] Phytoestrogens can act as both estrogen agonists and antagonists by binding to estrogen receptors

[0013] . The use of phytoestrogens as a treatment for menopausal symptoms has yielded significant results, according to several studies [14, 15, 16]. In a study, it was observed that orally taken phytoestrogens had no effect on vaginal symptoms

[0017] . Therefore, local treatments are expected to attract more attention on these symptoms. Phytoestrogens are divided into three main classes as isoflavones, lignans and coumestans. Hyaluronic acid (HA) in the formulation of the invention, which is currently used in many facial fillers, is a natural polysaccharide from the glycosaminoglycan family and forms an important part of the extracellular matrix of the skin and cartilage, including the vaginal mucosa. HA has the capacity to hold water molecules 1000 times its weight and plays a key role due to its properties such as the formation and protection of extracellular swelling, increasing the water holding capacity in the vulva-vaginal area, moisturizing the skin in case of inflammation and maintaining the water balance. It is also widely effective in the treatment of skin diseases, since it preserves tissue consistency, facilitates cellular migration in cases of inflammation, and facilitates the healing and regeneration process of tissues

[0018] . Promising results of HA on physical and sexual symptoms associated with vaginal atrophy have been reported in the literature [19, 20, 21]. Most of these studies have focused on the subjective assessment of symptom response to topically applied preparations. However, HA is an endogenous molecule and it is known that its effects are best exhibited when injected into the superficial epithelial layers.

[0028] In the international patent document no W02019003053, an application known in the state of the art, the invention demonstrates that a formulation comprising molecular oxygen and hyaluronic acid is effective in the topical treatment of vaginal disorders. This invention is used in the treatment of vaginal dryness and vulvovaginal atrophy. The oxygen used in the said invention is used as a vehicle for hyaluronic acid and also works as an enhancer of hyaluronic acid permeability. For this reason, it facilitates protein absorption by stimulating tissue regeneration as well as local microcirculation.

[0029] In the United States patent document no US20120052077, an application known in the art, the invention relates to management of vaginal health. The said application relates to pharmaceutical compositions, and methods of use thereof, for treating diseases associated with compromised boundary lubrication at the vaginal epithelium. Provided herein in certain embodiments is a method for treating a lack of vaginal lubrication or associated symptoms in an individual in need thereof, comprising topical application to the surface of the vagina, and comprising a therapeutically effective amount of PRG4 protein.

[0030] In the patent document no WO2017089475, an application known in the state of the art, the invention relates in general terms to a pharmaceutical composition for topical application, comprising an effective combination of hyaluronic acid, betaglucan, hydrolyzed sericin, and glycerophosphoinositol or a pharmaceutically acceptable salt thereof, useful in particular as a cicatrizing agent for the treatment of micro- cracks and vulvar and / or vaginal epithelium wounds.

[0031] In the European patent document no EP 1673063 , an application known in the state of the art, the invention relates to relates to transdermal pharmaceutical composition consists of an estrogen and a progestin component as well as a liquid crystal gel containing polyoxyethylene-glyceryl-trioleate, propylene-glycol, isopropyl myristate and a hyaluronic acid salt or complex. The said invention is a treatment method to be used in the treatment of urinary incontinence symptoms due to urogenital atrophy, vaginal dryness, recurrent vaginitis, recurrent cystitis, painful sexual intercourse and postmenopausal estrogen deficiency.

[0032] Summary of the Invention

[0033] The objective of the invention is to obtain hyaluronic acid hydrogel comprising phytoestrogens- which are herbal substances with the same structure and functions as estradiol (Oestradiol or estradiol, an estrogenic steroid hormone) and which can produce estrogenic effects, to be used for the treatment of vaginal atrophy and vaginal rejuvenation.

[0034] Another objective of the present invention is to avoid encountering risks such as heart attack, stroke and blood clotting seen in alternative treatment methods comprising hormones. Detailed Description of the Invention

[0035] The hydrogel formulation of the invention, which is suitable for use in vaginal tissue, is prepared in phosphate buffer or phosphate-free buffer solution and comprises

[0036] • at least one of linear-linked forms of sodium hyaluronate, cross-linked forms of sodium hyaluronate, and combinations thereof,

[0037] • phytoestrogens selected from a group comprising isoflavones, lignans and coumestans and combinations thereof,

[0038] • vitamins and antioxidants.

[0039] In an embodiment of the invention, the invention comprises linear and / or crosslinked forms of sodium hyaluronate with a molecular weight of 100 x 103Da - 3.5 x 106Da (determined by intrinsic viscosity values), and is present in the formulation in the concentration range of 5 mg / ml - 30 mg / ml. By this means, it is ensured that the final product exhibits visco-elastic properties depending on the use of sodium hyaluronate at the specified ranges.

[0040] In an embodiment of the invention, isoflavones in the formulation are in the concentration range of 0.01 mg / ml - 20 mg / ml and are selected from a group comprising geninstein, daidzein, quercetin, glycitein, formononetin, equol, o- desmethlangolensin, dihydrodaidzein, biochanin and combinations thereof.

[0041] In one embodiment of the invention, the lignans in the formulation are in the concentration range of 0.01 mg / ml - 20 mg / ml and are selected from a group comprising enterodiol, enterolactone, pinoresinol, secoisolariciresinol, matairesinol, sesamin and combinations thereof

[0042] In one embodiment of the invention, the coumestans in the formulation are in the concentration range of 0.01 mg / ml - 20 mg / ml and are selected from a group comprising coumestrol, wedelolactone, plicadin, and combinations thereof. Vitamins are essential for maintaining a healthy uterus and vagina. Vitamins are involved in the metabolism of all cells and prevent tissue damage caused by oxidants. They also play an important role in balancing estrogen levels, thereby improving menopausal symptoms such as hot flashes, irritability, insomnia, dizziness, palpitations, shortness of breath, and vaginal dryness. It can be used locally on the skin as an active healing agent due to its antioxidant and antiinflammatory properties and can reduce vaginal dryness when used topically. In an application of the invention, the vitamins in the formulation are in the concentration range of 0.05 mg / ml - 30 mg / ml and are selected from a group comprising B group vitamins, namely thiamine (Vitamin Bl), riboflavin (Vitamin B2), niacin (Vitamin B3), panthenol (Vitamin B5), pyridoxine (Vitamin B6); vitamin D; vitamin E; and combinations thereof.

[0043] The antioxidant addition in the formulation of the present invention neutralizes the ROS associated with vaginal inflammation that occurs during vaginal atrophy, thereby protecting the vaginal epithelium and stroma from oxidative damage. Thus, it facilitates the healthy regeneration of the lamina propria and vaginal epithelium layer. As a result, it will help the area rehydrate and expand to maintain elasticity, firmness and the proper functioning of female genital tissue. In addition, this helps to reduce the swelling that may occur after the injection. In one embodiment of the invention, the antioxidants in the formulation are selected from the group comprising glutathione, allicin, astaxanthin, N-Acetylcarnosine (NAC), epigallocatechin gallate (EGCG), coenzyme Q10 (CoQlO), alpha tocopherol, pyruvate, carotene, beta carotene, trolox, xanthan gum, hydroxytyrosol, tyrosol, caffeic acid, rutin, diosmin, melatonin, taurine, hypotaurine, vitamin C derivatives L-ascorbic acid, tetrahexyldecyl ascorbate, ascorbyl glucoside, ethylated ascorbic acid, ascorbyl palmitate, magnesium ascorbyl palmitate, magnesium ascorbyl phosphate, calcium ascorbate, sodium ascorbate, sodium ascorbyl phosphate and combinations thereof. In one embodiment of the invention, the formulation is stored in disposable sterile syringes before use.

[0044] The hyaluronic acid in the formulation of the present invention has a short halflife. In other words, it biodegrades in a short time where it is injected. Therefore, crosslinking is required to stabilize the product, and after this crosslinking reaction, the product reaches a hydrogel form. With this process, it will remain in the area where it is injected for a longer time and it will be able to maintain its moisturizing properties for several months. For this reason, the cross-linking agents to be used in cross-linking reaction in order to obtain hyaluronic acid hydrogels are selected from a group comprising 1,4-butanediol diglycidyl ether (BDDE), divinyl sulfone (DVS), l-(3- dimethylaminopropyl) -3- ethylcarbodiimide (EDC) / N-hydroxysuccinimide (NHS) combination, glutaraldehyde, adipic acid dihydrazide and combinations thereof.

[0045] Before the sterile hydrogels to be produced within the scope of the present invention are injected, local anesthesia should be applied to the relevant area for an effective painless treatment. It is then injected very superficially into the labia majora, vulvar area, or just under the mucous tissue at the vaginal opening. Preferably 27 GW or 30 GW needles should be used during injection.

[0046] The hydrogels to be produced within the scope of the invention can be used for vaginal rejuvenation as well as the treatment of symptoms such as dryness and itching caused by vaginal atrophy. As women age, like many other parts of the body, the labia majora (the outermost labia surrounding the vagina) loses its elasticity due to tissue loss. Changes in this region may worsen after childbirth and menopause, leading to both appearance and functional concerns. The hydrogels to be produced within the scope of the invention plump up these areas that have lost elasticity and improve their appearance. The method developed for preparing the formulation of the present invention comprises the following steps:

[0047] - preparing 1% NaOH solution in deionized water,

[0048] - slowly adding HA onto the said solution and dissolving it,

[0049] - adding the cross-linking agent to the HA mixture and mixing it homogeneously,

[0050] - incubating the mixture in a water bath at 40-50 °C for 2-5 hours, and leaving it for crosslinking reaction,

[0051] - neutralizing the gel with 0.1 M hydrochloric acid (HC1) until pH becomes 6.8-7.4 in buffer solution after reaction,

[0052] - filtering the mixture and washing it 5-10 times with fresh buffer solution,

[0053] - reducing the gel to particle sizes of 100-500 microns (so that gels can be injected more easily from the tip of the syringe needle),

[0054] - adding non-crosslinked HA to facilitate extrusion, and adding phytoestrogens and antioxidants as active ingredients to the final mixture,

[0055] - adjusting the pH of the final mixture to 6.8-7.4 and filling it into the syringes under vacuum,

[0056] - sterilizing the filled syringes by performing steam sterilization process,

[0057] - labelling and packaging the final products.

[0058] Thanks to the hormone-free formula of the hydrogels produced within the scope of the invention, as an important advantage, they will not pose risks such as heart attack, stroke and blood clotting seen in alternative treatment methods comprising hormones. In addition, the phytoestrogens in the formulation are herbal substances that can produce estrogenic effects and have the same structure and functions as estradiol. REFERENCES

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Claims

CLAIMS A hydrogel formulation suitable for use in vaginal tissue, characterized by- buffer solution,- at least one of linear-linked forms of sodium hyaluronate, cross-linked forms of sodium hyaluronate, and combinations thereof,- antioxidants,- phytoestrogens selected from a group comprising isoflavones, lignans and coumestans and combinations thereof. A hydrogel formulation according to claim 1, comprising linear and / or cross-linked forms of sodium hyaluronate with a molecular weight of 100 x 103Da - 3.5 x 106Da. A hydrogel formulation according to claim 1 or 2, comprising linear and / or cross-linked forms of sodium hyaluronate in the concentration range of 5 mg / ml - 30 mg / ml. A hydrogel formulation according to claim 1, comprising isoflavones in the concentration range of 0.01 mg / ml - 20 mg / ml. A hydrogel formulation according to claim 1 or 4, comprising isoflavones selected from a group comprising geninstein, daidzein, quercetin, glycitein, formononetin, equol, o-desmethlangolensin, dihydrodaidzein, biochanin, and combinations thereof. A hydrogel formulation according to claim 1, comprising lignans in the concentration range of 0.01 mg / ml - 20 mg / ml.A hydrogel formulation according to claim 1 or 6, comprising lignans selected from a group comprising enterodiol, enterolactone, pinoresinol, secoisolariciresinol, matairesinol, sesamin, and combinations thereof. A hydrogel formulation according to claim 1, comprising coumestans in the concentration range of 0.01 mg / ml - 20 mg / ml. A hydrogel formulation according to claim 1 or 8, comprising coumestans selected from a group comprising coumestrol, wedelolactone, plicadin and combinations thereof. A hydrogel formulation according to claim 1, comprising vitamins in the concentration range of 0.05 mg / ml - 30 mg / ml. A hydrogel formulation according to claim 1 or 10, comprising vitamins selected from a group comprising B group vitamins, namely thiamine (Vitamin Bl), riboflavin (Vitamin B2), niacin (Vitamin B3), panthenol (Vitamin B5), pyridoxine (Vitamin B6); vitamin D; vitamin E; and combinations thereof. A hydrogel formulation according to claim 1, comprising antioxidants in the concentration range of 0.05 mg / ml - 30 mg / ml. A hydrogel formulation according to claim 1 or 12, comprising antioxidants selected from a group comprising glutathione, allicin, astaxanthin, N-Acetylcarnosine (NAC), epigallocatechin gallate (EGCG), coenzyme Q10 (CoQlO), alpha tocopherol, pyruvate, carotene, beta carotene, trolox, hydroxytyrosol, tyrosol, caffeic acid, rutin, diosmin, melatonin, taurine, hypotaurine, vitamin C derivatives L-ascorbic acid, tetrahexyldecyl ascorbate, ascorbyl glucoside, ethylated ascorbic acid, ascorbyl palmitate, magnesium ascorbyl palmitate, magnesium ascorbylphosphate, calcium ascorbate, sodium ascorbate, sodium ascorbyl phosphate and combinations thereof. A hydrogel formulation according to claim 1, comprising cross-linking agents to be used in cross-linking reaction of hyaluronic acid hydrogels, and selected from a group comprising 1,4-butanediol diglycidyl ether (BDDE), divinyl sulfone (DVS), l-(3- dimethylaminopropyl) -3- ethylcarbodiimide (EDC) / N-hydroxysuccinimide (NHS) combination, glutaraldehyde, adipic acid dihydrazide and combinations thereof. A hydrogel formulation according to Claim 1, which is stored in disposable sterile syringes. A hydrogel formulation according to Claim 1, which is injected superficially to the labia majora, vulvar area or right under the mucous tissue at the vaginal opening, where local anesthesia is applied. A hydrogel formulation according to any one of claims 1 to 16, which is used for the treatment of dryness and itching symptoms caused by vaginal atrophy, and vaginal rejuvenation. A hydrogel formulation according to any one of claims 1 to 16, which is used for plumping and improving the appearance of labia majora areas which lose elasticity due to age-related tissue loss. Production method of a hydrogel formulation according to any one of the preceding claims, comprising the steps of- preparing 1% NaOH solution in deionized water,- slowly adding HA onto the said solution and dissolving it,- adding the cross-linking agent to the HA mixture and mixing it homogeneously,- incubating the mixture in a water bath at 40-50 °C for 2-5 hours, and leaving it for crosslinking reaction,- neutralizing the gel with 0.1 M hydrochloric acid (HC1) until pH becomes 6.8-7.4 in buffer solution after reaction, - filtering the mixture and washing it 5-10 times with fresh buffer solution,- reducing the gel to particle sizes of 100-500 microns,- adding non-crosslinked HA to facilitate extrusion, and adding phytoestrogens and antioxidants as active ingredients to the final mixture,- adjusting the pH of the final mixture to 6.8-7.4 and filling it into the syringes under vacuum,- sterilizing the filled syringes by performing steam sterilization process,- labelling and packaging the final products.