RO127721A2 - Pharmaceutical cream-type preparations based on metal complexes of chlorhexidine and process for preparing the same - Google Patents

Abstract

The invention relates to a pharmaceutical preparation of the cream type having antimicrobial, antifungal, anti-inflammatory and wound healing effects and to a process for preparing the same. According to the invention, the preparation comprises 0.01...0.1% metal complexes of chlorhexidine with Cu(II), Zn(II), Ag(I) in association with usual excipients. The process claimed by the invention consists in hot emulsifying the weighed starting materials, followed by trituration until the product is cooled and conditioning of the final product.

Description

DESCRIPTION OF THE INVENTION

The present invention relates to pharmaceutical preparations of type creams based on metal complexes of chlorhexidine and to a process for obtaining them. The topical pharmaceutical preparations for external use of creams type, are intended for the field of human and veterinary health as appropriate, regarding the disinfectant and antifungal action, and can be used for the treatment of the skin as a dermatological germostop.

In recent years there is a concern and an increased demand for antimicrobial agents commonly marketed, as the main active ingredients in addition to alcohols, iodine, iodoform, hexachlorophen and chlorhexidine (CHX). CHX is active against Gram positive bacteria and less active against Gram negative bacteria, fungi, and Proteus species; it has activity only against certain types of viruses (hepatitis, herpes simplex, HIV, cytomegalovirus and respiratory virus). CHX - reduced activity against mycobacteria and null for endospores and protozoan cysts. CHX acts on: the cell membrane causing its destruction and loss of intracellular material, respiratory inhibition and cytoplasmic coagulation.

Chlorhexidine (DCI) is a strong base with low water solubility. To increase water solubility, CHX forms salts with acids: gluconic acid (CHX-digluconate 20g / 100 mL, CHX-acetate 1.9 g / 100 mL) [US 2006/0051385 Al],

Regarding the nature of the metal ions used as coordination centers, a large number of studies target complexes of metals with significant biological relevance, such as zinc, copper and silver. Of the biological actions specific to these metal ions, the greatest interest has been aroused by their antimicrobial activity and their healing [Bryan Greener, Antimicrobial biguanide metal complexes, J. Pharmaceutical Sciences, 69 (2), 215-217, 2006], [Farrigton, K.L. , Morrow, LE, Antimicrobial Metals: A Nonantibiotic Approach to Nosocomial Infections - Silver and copper may prove key in preventing a problem that kills nearly 88,000 per year, 2005, www.rxmed.com/monographs]. The complex combination of Ag (I) with sulfodiazine, a coordination polymer in which the Ag ⁺ ion is pentacoordinated, is a much more effective antibacterial agent compared to the free ligand against bacterial strains, such as Pseudomonas aeruginosa and Staphylococcus aureus [US 20030035848 Al / 2003], [US 2002/0072480 A].

Pharmaceutical preparations of the type antimicrobial activity creams, proposed within the patent, intended for the exercise of the disinfectant action of the metal complexes through a synergistic effect due to the combination of the antibacterial and antifungal action of the chlorhexidine and its derivatives with that of the metal ions, Zn, Cu and Ag. with increasing therapeutic efficacy, they can be used for the treatment of teguments as a dermatological germostop for veterinary use.

The antibacterial capacity of the silver ions is correlated with the oxidation state and it is proven that the silver ions in oxidation states II and III have a better / more efficient and stronger antibacterial action than Ag (I). However, AgNCȚ and other complexes, such as Ag (I) -sulfadiazine, are effective antibacterial agents with Ag (I). An Ag (III) -CHX nanocrystalline complex - synthesized by reverse microemulsion technique - exhibited strong antibacterial activity on Gram-positive bacteria (Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228) Propionibacterium acnes (ATCC 6919)) and Gram-negative (Acinetobacter calcoaceticus (ATCC 23055), Citrobacter freundii (ATCC 6750), Klebsiella pneumonia (ATCC 10031), and Pseudomonas aeruginosa (ATCC 27853)) and on Stureococcus methicoccin-resistant strains. . The minimum inhibitory (MIC) concentrations of Ag (III) -CHX complex were much lower than those of the free ligand, (chlorhexidine base), AgNCȚ and [Synthesis of Highly Antibacterial Nanocrystalline Trivalent Silver Polydi Eun Jeong Yoon, Yu Kyung Tak, Eung Chil Choi, and Joo

......... 2tyfiJ3I, 16147-16155].

adiazina

^l 9

¢ -2010-01224-2 9 -1b 2010

Chlorhexidine complexes with Ag (III) were obtained in the form of stable compositions at ambient temperature, compatible with the materials used as substrate in medical devices, and were used in the treatment or prophylaxis of microbial (bacterial) infections [US WO 2007/000590 Al ], [US 2006/0051385 A],

The antimicrobial action of such CHX-Ag (III) complexes is superior to that of the free ligand or Ag (I) ion in the compounds AgNO ₃ or Ag (I) -sulfadiazine, already used in the clinical treatment of bacterial infections. Articles for medical use (antiseptic film instrumentation, eg intubation probes - avoiding nosocomial infections, bioadhesive antimicrobial dressings) produced by impregnation with CHX-Ag (III) (by immersion in the complex solution) or by coating with CHX-Ag (III ) powders can be stored for long periods (several years) at ambient pressure and temperature in traditional sterile packaging. CHX-Ag (III) dispersed by mechanical mixing in IntraSite Gel (Smith & Nephew Medical Ltd.) results in a chemically stable hydrogel with antimicrobial action against Staphylococcus aureus (area of inhibition = 6.4 mm), Pseudomonas aeruginosa (area of inhibition = 5.4 mm) [US 2002/0072480 A], [US WO 2007/000590 A],

CHX complexes with Ag (I) and Ag (II): [Ag (CHX)] ⁺ and [Ag (CHX)] ²⁺ showed higher antibacterial activity and higher lethal speeds compared to chlorhexidine and AgNO3 and may represent a the new generation / class of antibacterial agents in the treatment of wounds. These [Ag (CHX)] (NO3) and [Ag (CHX)] (NO3) 2 complexes were synthesized by precipitation from neutral or weakly acidic (H2SO4, 2N) aqueous solutions of chlorhexidine (CHX) and AgNO3. [Ag (CHX)] (NO3) 2 with Ag (II) complex was obtained in 2 steps: oxidation of Ag (I) from CHX: AgNO3 solution with sodium sulfate (Na2S2O8), formation of CHX: Ag (II) complex [Metallopharmaceuticals based on silver (I) and silver (II) polydiguanide complexes: activity against burn wound pathogens, Pal S, Yoon EJ, Park SH, Choi EC, Song JM, J Antimicrob Chemother. 2010; 65 (10): 2134-40], The antibacterial activity of these complexes was determined by determining MIC and MBC concentrations on 4 Gram-positive and 4 Gram-negative bacteria: Acinetobacter calcoaceticus, Pseudomonas aeruginosa, Citrobacter freundii, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae. MIC concentrations for [Ag (CHX)] ⁺ and [Ag (CHX)] ²⁺ complexes were much lower than those of chlorhexidine, AgNO3 and the Ag-sulfadiazine complex. The lethal velocities of the complexes [Ag (CHX)] ⁺ and [Ag (CHX)] ²⁺ on the bacteria tested were 2-8 times higher than those corresponding to chlorhexidine or AgNO ₃ at concentrations equal to MIC or 4 times higher than this.

In clinical studies, oral care products (toothpaste, mouthwash) containing chlorhexidine mixtures: Zn (II) have been shown to be more effective in controlling the formation of dental plaque, gingivitis and volatile sulfur compounds in the oral cavity ( ie, breathless breath, halene) than the products that have only chlorhexidine.

Mouth water with CHX is extensively used as an adjuvant in the treatment of periodontitis and there are preliminary studies showing that CHX inhibits numerous glycosidic and proteolytic activities of oral bacteria, e.g. P.gingivalis [Inhibition of Porphyromonas gingivalis proteininases (gingipains) by chlorhexidine: synergistic effect of Zn (II), CA Cronan, J. Potempa, J. Travis, J. A. Mayo, Oral Microbiology Immunology 2006: 21: 212-217], Activities enzymes responsible for gingival pain lys (Kgp) and arg (2 forms, RgpB and HrgpA) were measured in the presence of varying concentrations of CHX and in the presence of CHX: Zn. Inhibition constants (K,) were determined in both cases. RgpB, HrgpA and Kgp were inhibited by chlorhexidine with K, with micromolar domain values. For RgpB and HrgpA, the inhibitory effects of CHX were potentiated 30-fold upon the addition of Zn (II). The CHX-Zn (II) interaction causes a synergistic effect in inhibiting HrgpA and RgpB. For Kgp, the effects of Zn (II) and CHX on inhibitory activity were antagonistic

Zinc and chlorhexidine ions have a synergistic inhibitory effect on growth of sobrinus and sanguis. The effects on the bacterial were determined for 8.0 'GHX and the combination of the two combinations [E.

Scandinavian Journal of DentalJ & ^search,, 'STlTl'TUI be ^SA T'f »Al. _OE KNTKi-

A.- 2010-01224-2 9-11-11

Zinc ions, chlorhexidine (CHX) and cetylpyridinium chloride are known compounds for inhibition of volatile S-based compounds (VCS). Zinc ions at 1% have an unpleasant taste, it is desirable to be efficient at lower concentrations.

CHX has an unpleasant 0.2% taste. Zn has the best anti-VCS effect in the concentration of 1%, lh, CHX has the same effect at 0.2%, in 3h [A. Young, G. Jonski, G. Rolla, European Journal of Oral Sciences, 2003,111 (5), 400.].

Copper is a metal of clinical interest, an essential metal in human nutrition and has low toxicity.

Chlorhexidine and Cu ²⁺ , 1.1 mM solutions were used in experiments aimed at reducing bacterial plaque. Chlorhexidine, at 1.1 mM, is more efficient than Cu ²⁺ [MS Waler, G. Rolla, Scandinavian Journal of Dental Research, 1982, 90 (2), 131-133].

Complexes based on CHX-I are found in the following formulations: [GB1128833 / 1966] and [PEP1340490B1 / 2003], chlorhexidine-based mouthwash, as a solution for oral hygiene based on chlorhexidine and ascorbic acid, which has no side effect pigmentation of the teeth. To the solution of chlorhexidine and ascorbic acid (with the role of reducing Fe ³⁺ to Fe ²⁺ , preventing Maillard reactions), sodium metabisulphite is added which has the role of stabilizing ascorbic acid (preventing its oxidation) in aqueous solution. With sodium citrate the pH of the mouthwash is kept at values: 5.7-6.3, area in which the activity of chlorhexidine is maximum

Other patents containing chlorhexidine compounds [WO 03/096999 Al], Formulations for masking unpleasant taste (composition 1.4% wt. NaF, 4.3% wt. Chlorhexidine acetate, 14.3% aspartame, 74.0-74.3% microcrystalline cellulose, 5.7% polyoxyethylene glycol 4000, 0.0-0.3% peppermint oil; [WO 03/084461 A2], Oral formulations containing chlorhexidine or salts (digluconate, diacetate, dihydrochloride), zinc salt, zinc gluconate and masking / flavoring agent - saccharine or saccharin salt; [US 2005/0191247 Al], chlorhexidine complexes with Cu ²⁺ and Zn ²⁺ salts, are present in concentrations of 1%, 0.5%, 0.1%, at least 0.01%.

Currently, a significant number of antiseptic drugs are produced and marketed as containing the active substance chlorhexidine, administered in the form of solutions, mouthwashes or gels, for external use, such as OTC [1], Medical Agenda. Medica Publishing House, Bucharest, 2009, Memomed, 15th Edition, Minesan Publishing House and University Publishing House, 2009, in:

1. Oral-dental disorders, prosthetics-orthodontics (Corsodyl Mint Mouthwash solution - SmithKline Beecham / England; Corsodyl gel - SmithKline Beecham / England; Chlorhexidin Dental solution - ACO; Plack out solution -Santa / Greece; Plack out gel - Santa / Greece ; Peridex - Procter & Gambie Comp .; Dentosmin-P- Arzneimittelwerk / Germany; Trachisan- Engelhard / Germany)

2. Skin, gynecological and surface antiseptic disorders (Betagin - Biofarm S.A./Romania; Chlorhexidine-Gifrer Barbezat / France; Chlorhexidine gluconate - Ferrosan; Chlorhexidine-Biopharm

S.A./Romania; Clohexin-A, -B, -C- Pharma Labor / Romania; Desmanol- Schulke Mayr / Germany; Hibiscrub - Zeneca Ltd./Anglia; Hibitane - ICI-Zeneca / England; Septofort - Pharmavit)

Disadvantages or limits of chlorhexidine present as active principle in the current pharmaceutical preparations marketed:

Transforming the ligand into a water-soluble form. CHX (free base) is insoluble in water and exists only at pH> 12. CHX is used as the salt of some organic acids: CHX diacetate, CHX dihydrochloride, CHX digluconate. However, the possibility of unwanted interactions of the metal ion with other organic or inorganic species or co-precipitation makes these species - sources not very suitable for CHX ligand. Since pKa values for CHX (2.2 and 10.3) show that CHX is diprotonated over the entire range of physiological pH values, its solubilization can be easily achieved by treatment with diluted H2SO4 and conversion to CHX ²⁺ -2 (HSO4 ^_ ). .

The limitations of chlorhexidine present as an active principle in the present commercialized forms, consist in obtaining liquid pharmaceutical forms (mouthwashes) which. .. a. Chlorhexidine concentration at _____ level, limiting the antimicrobial activity cqjElftir ^ tife

Z ιχ'τιτι rut Ț ^λ 'Ι ·' · \ 5 (. Nt r>'A'TMRI ^m u „, - · Υ

oral by the diqcran / utiU

I

and Λ.

Ο 1 0 - 0 1 2 2 4 - 2 9 -IF 2010

The technical problem that the invention solves and what disadvantages the invention eliminates:

By combining chlorhexidine and its salts, with metal ions with their own pharmacological activity (antibacterial, antifungal, healing, anti-inflammatory) in compounds with disinfectant and antifungal properties, problems caused by the use of free CHX can be eliminated.

The invention solves the following biopharmaceutical problems, namely:

- increasing the contact of the preparation with the skin, respectively topical route, for external use, respectively prolonging the therapeutic action, as well as the possibility of using new compounds not used in therapeutics, active in vitro at lower concentrations compared to the chlorhexidine salts used.

- elimination of adverse reactions (irritant contact dermatitis -CHX free)

- finding a pharmaceutical formulation / composition that has a solubility in aqueous media above the minimum inhibitory concentration (MIC) of the treated organism

- the choice of excipients so as to avoid the formation of insoluble complexes CHX - anionic excipient - chemically stable pharmaceutical preparations in the pH range - 5.5-7, the maximum efficiency range of CHX.

- avoiding contamination of the product in the synthesis process - to keep the biological activity unaltered.

The process of obtaining pharmaceutical preparations of type creams based on metal complexes of chlorhexidine according to the invention has the following advantages:

- Formulation of U / A or A / U emulsion ointments using as the chlorhexidine diacetate complex with Cu (II) and Ag (I) salts allows the use of preparations for local topical action

- the pharmaceutical form falls within the official quality parameters

- the antimicrobial activity evaluated in vitro showed the potentiation of the activity towards the chlorhexidine and the metal salts.

In order to obtain the pharmaceutical preparations of the cream type according to the invention, chlorhexidine-based metal complexes were used as active substances using the two-phase U / A emulsion base, an external phase represented by water or an aqueous solution and an internal phase. which is composed of lipophilic excipients, components with emulsifying properties necessary for stabilizing the system.

These emulsifiers are not sufficient to ensure the stability of the ointments and are usually associated with lipophilic emulsifiers that stabilize the interfacial film and increase the internal phase viscosity, resulting in compound emulsifiers (Lanette waxes).

The cetyl stearyl alcohol, paraffin oil, petroleum jelly are fluidized in the water bath; separately, the solution of p-hydroxybenzoate of propyl - p of methyl hydroxybenzoate (1: 3) is heated on the screen and polyoxyethylene-20 sorbitan monooleate and the active substance, metal complexes of chlorhexidine, are added to this solution. Over the lipophilic mixture is added in a thin wire, the hydrophilic phase heated to the same temperature, then triturated until cooled for homogenization.

The A / U emulsion ointment bases are prepared by dispersing the aqueous phase into the melted fat phase in which the emulsifier was incorporated and mixing until cooling; Both phases must have approximately the same temperature. These ointment bases contain lipophilic excipients as external phase and water or an aqueous solution as internal phase; they have components with emulsifying properties, for example lanolin, wool alcohols, cholesterol, wax, span, cetacean (which have weaker emulsifying properties).

When applied to the skin it leaves a greasy trace that does not remove with water. After preparation, the creams obtained are subjected to quality control, in which the organoleptic properties are determined, the mass homogeneity, the mass uniformity, the pH, the consistency, the display capacity, the hardness and the relative density, according to FRX and are conditioned in aminoplast boxes, in a cool place. , protected from light

Two non-limiting examples of the invention are given, in connection with Table no. 1 and with Figure no. 1, which represents the technological scheme of the cream process based on chlorhexidine metal complexes.

cV2 Ο 1 Ο - Ο 1 2 2 4 - 2 9 -η- 2010

Table 1. Non-limiting examples of the invention

Name of the substance Quantity g (%) Example 1 Example 2 1,1'-hexamethylene-bis- [5- (4-chlorophenyl) - biguanido] copper and silver diacetate 0.01-0.1 0.05-0.1 Cetostearyl alcohol 10-20 - Polyoxyethylene-20 sorbitan monooleat 1 -10 - Vaseline 10-20 10-20 Paraffin oil 5-15 15-20 Lanolin 10-18 Wax 1 -3 cetaceum 10-20 cholesterol 1 -2.5 Propyl p-hydroxybenzoate solution of methyl p-hydroxybenzoate (1: 3) 35 - 75 15-53

Cream pharmaceutical preparations according to the invention are obtained, with the physical and chemical characteristics of Table no. 2.

Table no. 2. Physico-chemical characteristics of pharmaceutical preparations based on creams

comp and metal chlorhexidine Characteristic Results Organoleptic examination creamy, white - pink, odor - free preparations Homogeneity homogeneous appearance without air bubbles, droplets or particle agglomeration pH 5.5 - 6, 25 Display capacity 300- 1600 mm ² Penetration ability 9.50 - 20.00 mm

The process of obtaining the pharmaceutical preparations of the type creams according to the invention consists of the following technological scheme presented in Figure no.

C \ r2 IU C - 0 1 7 74 - -

IL-ZJlU following a study on antimicrobial activity, it was observed that the pharmaceutical preparations of type creams based on metal complexes of chlorhexidine, have an increased antimicrobial activity against the microbial strains Staphylococcus aureus coli (inhibition diameter 1-16 mm), Escheria coli 1, 16 mm) (inhibition diameter 1 - 9 mm) and Candida albicans coli (inhibition diameter 1 - 8 mm) compared to the organic ligands and the complex combinations from which they were obtained.

Topical pharmaceutical preparations for external use based on chlorhexidine metal complexes, conditioned in the form of creams, have been tested in vitro in fibroblast cultures. In order to test the effect of the studied compounds on the cells, the cell viability (using the MTT method) and the cell morphology were analyzed. Cytotoxicity was tested by the extract method (in the case of products conditioned in the solid form), taking into account several concentrations of the extracts and several degrees of dilution of the products in solution form. The obtained results demonstrated a pronounced cytotoxic effect of the products in the form in which they were obtained, compared with the control cell sample. At concentrations less than 100pg / mL of the conditioned product in the form of cream, no changes in fibroblast morphology were observed, as they have a viability of over 95% after 24 hours of cultivation in the presence of the respective extracts.

Testing the antioxidant activity of the pharmaceutical preparations of type creams based on metal complexes of chlorhexidine according to the invention, by the chemiluminescence method, showed that they have values of antioxidant activity in the range of 50-95%, indicating them as efficient antioxidant agents.

Claims (3)

1. Pharmaceutical preparations of type creams based on metal complexes of chlorhexidine, characterized in that they consist of the active principle metal complexes of chlorhexidine (0.01 - 0.1%), cetostearyl alcohol (10 - 20%), vaseline (10 - 20 %), paraffin oil (5-20%), lanolin (10-18%); wax (1-3%), cetaceum (10-20), cholesterol (1 2.5%); polyoxyethylene-20 sorbitan monooleate (1 - 10%), methyl p-hydroxybenzoate solution - methyl phydroxybenzoate (1: 3) (15 - 75%), the percentages by weight. 2. Pharmaceutical preparations of cream type based on chlorhexidine metal complexes according to Claim 1, characterized in that they are presented in the form of creamy, white-pink, odorless, homogeneous appearance without air bubbles, drops or particle clusters with a slightly acidic pH. 3. The process for obtaining pharmaceutical preparations of the type creams based on metal complexes of chlorhexidine according to Claim 1, characterized in that the cetyl stearyl alcohol, paraffin oil, petroleum jelly are fluidized in the water bath; Separately, the propyl - hydroxibenzoate solution of methyl p (1: 3) is heated on the screen and polyoxyethylene-20 sorbitan monooleate is added to this solution. Over the lipophilic mixture is added in a thin wire, the hydrophilic phase heated to the same temperature, then triturated until cooled for homogenization. The A / U emulsion ointment bases are prepared by dispersing the aqueous phase into the melted fat phase in which the emulsifier was incorporated and mixing until cooling; both phases must have approximately the same temperature and contain lipophilic excipients as external phase and water or an aqueous solution as internal phase; they have components with emulsifying properties, for example lanolin, wool alcohols, cholesterol, wax, span, cetacean (which have weaker emulsifying properties). When applied to the skin it leaves a greasy trace that does not remove with water. The pharmaceutical preparations according to the invention are packed in aminoplast boxes and stored in a cool, light-free place. The pharmaceutical preparations according to the invention, topical for external use, have antimicrobial and antioxidant activity, having disinfectant and antimycotic action, are biocompatible, have low or negligible toxicity and are not polluting environmental factors.