RU2308970C1 - Antibacterial agent for treatment of intracellular infection - Google Patents

Abstract

FIELD: medicine, pharmacy.

SUBSTANCE: invention proposes antibacterial agent that comprises moxifloxacin as a medicinal substance immobilized on polymeric carrier. As a polymer carrier the agent comprises nanoparticles of size 100-800 nm of lactic acid polymer/polymers and/or copolymer/copolymers of lactic acid and glycolic acid wherein the content of glycolic acid in indicated polymers is up to 50 mole% and wherein molecular mass of indicated polymers and copolymers is from 5 to 300 kDa. Also, agent comprises potassium cholesteryl sulfate or sodium glycocholate and a water-soluble natural or synthetic polymeric stabilizing agent of molecular mass 70 kDa, not above, chosen from group involving polyvinyl alcohol, polyvinylpyrrolidone, poloxamer, poloxamine and serum albumin and a filling agent in the amounts given in the invention claim. Agent can comprise additionally water as a solvent or water-containing mixtures. Invention provides the directed delivery of moxifloxacin to pathology focus and to regulate the rate of its releasing from polymeric matrix that provides reducing used doses of antibiotic, deceasing toxic effects and allows overcoming the resistance of infection pathogens.

EFFECT: improved and valuable properties of agent.

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Description

The invention relates to the field of medicine and pharmacology, specifically to drugs for the treatment of bacterial intracellular infections, especially pulmonary tuberculosis and septic infections.

In recent years, there has been a significant increase in the incidence of pulmonary tuberculosis in all countries of the world, which is associated with the emergence of resistant strains and the spread of diseases of the immune system, including AIDS. WHO estimates that by 2020, the number of newly infected with tuberculosis will reach 1 billion, 200 million will fall ill and 35 million will die from tuberculosis if new, more effective treatments are not found.

Among bacterial infections, the problem of sepsis, including nosocomial infection, is also becoming more urgent. This is due to an increase in the number of patients with sepsis, high mortality in this disease, and significant economic costs for its treatment. Thus, according to official statistics, in the USA in the 70-80s the number of registered cases increased 4 times: from 70,000 to 300,000 cases a year, and in the 90s to 600,000. The mortality rate in sepsis remains very high reaching 50%. The material costs of treatment are also high: in Europe, treatment of sepsis requires approximately three weeks of hospitalization in an intensive care unit, and the associated costs are estimated at 70-90 thousand dollars. The cost of subsequent rehabilitation treatment during the year can range from 100 to 250 thousand dollars.

The low effectiveness of the currently used antibacterial drugs is due to two main reasons. On the one hand, the number of patients with multidrug resistance is constantly growing due to the emergence of drug-resistant strains of microorganisms, which requires the use of new drugs with a wide antimicrobial spectrum of action. On the other hand, most drugs act non-selectively, that is, when the drug is introduced into the body, only an insignificant part of the drug enters the target organ / cell. In addition, most of the administered medicinal substances undergo biotransformation, without having an antibacterial effect. In this regard, it becomes necessary to introduce an excess amount of the drug substance, which leads to serious side effects in the form of impaired hematopoiesis, liver, kidney, and the like.

There are various ways to increase the effectiveness of antibiotic therapy. The administration of various immunomodulatory drugs to the patient along with antibiotics has become widespread (see, for example, RU 2266119, А61К 31/502, А61Р 31/06, 37/02, 20.12.2005; RU 2254872, А61К 38/20, А61Р 31 / 06, June 27, 2005; RU 2197984, A61K 38/08, A61P 31/06, 02/10/2003; RU 2242222, A61K 31/138, A61P 31/06, 12/20/2004). The use of antimetabolites, for example, fluorouracil, in combination with isoniazid is also known (RU 2211035, A61K 31/455, 31/513, A61P 31/06, 08/27/2003; RU 2185170, A61K 31/505, 31/513, 9/08 , А61Р 31/06, 07/20/2002). Means are proposed for increasing the sensitivity of microorganisms to antimicrobial agents (RU 2207863, А61К 33/00, 07/10/2003; RU 2255746. А61К 35/08, А61Р 43/00, 07/10/2005).

The most significant of the possible ways to increase the effectiveness of antibacterial drugs seems to us to be the development of targeted drugs that ensure the localization of the drug in target cells in effective amounts for therapy. At the same time, it is important that the ability to deliver the drug to the target is combined with a prolonged gradual release, which will reduce the used doses of the antibiotic. A large number of studies have been devoted to solving this problem, showing that when creating specific medicines, many specific problems arise, due to both the nature of the disease and the chemical properties of the drug.

To ensure the gradual isolation of the active ingredient from drugs, drugs are used in which the active principle is distributed in a biodegradable polymer matrix. Various forms of prolonged antibacterial drugs are known: in the form of tablets (RU 2146130, А61К 9/20, 31/455, 31/4965, 10.03.2000; RU 2246946, А61К 31/47, 02.27.2005), in the form of microgranules (RU 2003123513 , A61L 15/44, A61P 31/02, 01/27/2005), in the form of gels (RU 2241455, A61K 31/4164, 31/7072, A61P 27/02, 10.12.2004; RU 2226383, A61K 6/00, 7 / 16, A61P 1/00, 04/10/2004), in the form of solutions for inhalation (RU 2235537, A61K 9/08, 31/133, 31/395, A61P 31/06, 09/10/2004) or for injection (US 6264991 , MKI A61K 9/50, A61F 2/02, NKI 424/501, 424/426, 424/502, 07.24.2001). The disadvantage of most prolonged drugs is their inability to provide targeted intracellular drug delivery.

To increase the effectiveness of the drug inside the body, liposomal forms are used (L. Gubenko, Liposomal forms of antibiotics: pharmacokinetics at the cell and body level, effectiveness. - Kupavna, 1992; RU 2264827, A61K 45/08, A61K 9/127, 11/27/2005; RU 2223764, A61K31 / 496, A61K 9/127, 02.20.2004; RU 2122855, A61K 31/471, A61K 9/127, A61M 15/02. 12/10/1998). A disadvantage of liposome preparations is their low stability, since the phospholipids that make up the liposomes are easily oxidized.

Directional drugs are known in which a drug substance is chemically bound to a macromolecular carrier. An example of this approach is the covalent conjugate of isoniazid and dextran (RU 2087146, A61K 31/455, 31/70, 08.20.1997; RU 2143900, A61K 31/455, 47/48, 10.01.2000). The disadvantage of such drugs is the low capacity (drug: carrier ratio), as well as the complexity of the technology for creating such drugs.

Closest to the proposed invention is an antibacterial agent for the treatment of pulmonary infections, especially pulmonary tuberculosis (RU 2185818, A61K 9/08, 31/455, 31/7036, A61P 31/06, 07/27/2002 - prototype), which is a composition on the basis of a medicinal substance adsorbed on particles of polyalkylcyanoacrylates (C ₂ -C ₁₀ ) or their mixtures of 200-700 nm in size, also containing dextran with a molecular weight of 20-70 kDa and fillers in the following ratio of components, wt.%:

Polyalkylcyanoacrylate (or a mixture thereof) 20-40 Drug substance 1-10 Dextran 15-20 Fillers rest,

The composition may additionally contain a solvent in an amount of not more than 98 wt.% Of the total weight of the colloidal system, and may also contain surfactants (poloxamers, poloxamines, polysorbates, etc.) in an amount of not more than 20 wt.% From total weight of the aqueous colloidal system.

The well-known antibacterial agent selected for the prototype provides intracellular localization of the drug in alveolar macrophages in amounts effective for therapy, however, it has a number of significant drawbacks. Firstly, polyalkylcyanoacrylates have very high decomposition rates in a living organism, which significantly reduces the duration of drug release from the polymer matrix. Secondly, in Russia polyalkyl cyanoacrylates are not approved for use as components of medicinal products for internal use (although alkyl cyanoacrylates are widely used as medical adhesives, for example, in dentistry or surgery to cover wound surfaces; see, for example, RU 2156140, A61L 24/00, C09J 4/04, 09/20/2000). Thirdly, polyalkylcyanoacrylates must be synthesized from the corresponding monomers, and the preparation of particles of certain sizes (less than one micron) during the synthesis is a complex technological problem, resulting in insufficient stability of the characteristics of the obtained nanoparticles, which negatively affects the sorption properties of the polymer carrier. Finally, the monomers necessary for the synthesis of polyalkyl cyanoacrylates are not produced by Russian industry.

The objective of the invention is the creation of a prolonged antibacterial agent directed on the basis of commercially available biodegradable and biocompatible polymers, approved for use as auxiliary ingredients of drugs, which will maximize the manifestation of the inherent positive substance of the drug and will increase the effectiveness of treatment of intracellular infections, in particular tuberculosis and septic infections. In addition, the present invention will avoid the technologically complex and time-consuming process of synthesis of the polymer matrix.

The solution of this problem is achieved by the proposed antibacterial agent for the treatment of intracellular infections based on a drug substance immobilized on a polymer carrier, including targeted additives, which contains moxifloxacin as a drug substance, as a polymer carrier nanoparticles with a size of 100-800 nm polymer / polymers of lactic acid and / or a copolymer / copolymers of lactic and glycolic acids with a glycolic acid content in said copolymers of up to 50 mol%, wherein The molar mass (MM) of these polymers and copolymers is from 5 to 300 kDa, and the agent further comprises potassium cholesteryl sulfate or sodium glycocholate and a water-soluble natural or synthetic polymer stabilizer with a molecular weight of not more than 70 kDa selected from the group comprising polyvinyl alcohol , polyvinylpyrrolidone, poloxamer, poloxamine and serum albumin, and a filler in the following ratio of components, wt.%:

Specified polymer carrier 10-40 Moxifloxacin 1-5 Potassium Cholesteryl Sulfate or Sodium Glycocholate 0.01-5 The specified polymer stabilizer 5-20 Filler rest.

When adding a solvent (for example, water) in an amount of at least 80 wt.% Of the total weight of the product, the proposed product forms a microfine suspension with a particle size of 100-800 nm (the content of polylactides and / or lactide / glycolide copolymers in the resulting suspension is no more than 3 weight. %), which does not require additional introduction of surfactants for aggregate stability, however, it may contain suitable surfactants, for example, polysorbates, poloxamers, poloxamines, or polyhydric alcohols, for example polyethylene glycol or its functional derivatives, The number of no more than 15 wt.% of the total weight of the aqueous colloidal system.

As a solvent, water for injection, physiological saline, surfactant solutions and other aqueous mixtures suitable for injection can be used.

As a filler in the proposed tool can be used sugars with cryoprotective properties (for example, glucose, lactose, mannitol, trehalose) and salts (for example, sodium chloride, sodium citrate).

When choosing a drug source for the proposed antibacterial agent, it was necessary to take into account that most patients have multiple drug resistance, therefore antibiotics that are most common in the practice of treating tuberculosis and septic infections cannot provide high therapy efficacy. Moxifloxacin (MOX) is one of the best antibiotics of the last generation fluoroquinolone series; in addition, to date, it has not been used to treat tuberculosis.

The choice of polymer carrier was determined by the chemical properties of MOX and the task. Our experimental studies of several polymer carriers, such as polyalkyl cyanoacrylates, polymethylmethacrylate, polyacrylates, as well as homopolymers of lactic acid (polylactides, PLA) and copolymers of lactic and glycolic acids (PLGA), showed that, because of the specific chemical structure of MOX, not every polymer can use as a polymer matrix capable of sorbing and retaining a sufficient amount of MOX. Of all the studied polymers, the best sorption properties were shown by PLA and PLHA, as well as polyalkyl cyanoacrylates. However, as already mentioned, due to the high rate of biodegradation, polyalkyl cyanoacrylates do not provide a sufficiently long-term effect of MOX, while the rate of biodegradation of PLA and PGA is much lower (Vauthier C., Dubernet C., Fattal E., Pinto-Alphandary H., Couvreur P .Poly (alkylcyanoacrylates) as biodegradable materials for biomedical applications. Adv. Drug. Delivery Rev., 2003; 55 (4), p.519-548; Anderson JM, Shive MS Biodegradation and biocompatibility of PLA and PLGA microspheres. Adv. Drug . Delivery Rev., 1997; 28 (1), p. 5-24).

Further studies of the sorption process using the example of PLA and PLGA revealed a number of factors that significantly affect the efficiency of sorption, i.e., the amount of MOX adsorbed in polymer nanoparticles. It was found that the efficiency of sorption substantially depends on the chemical structure of the carrier polymer. In addition, the presence of free terminal carboxyl groups in the polymer also enhances the efficiency of incorporating MOX into the polymer nanoparticle. It unexpectedly turned out that the introduction of hydrophobic counterions into the preparation during the sorption process for the amino group MOX (potassium cholesteryl sulfate or sodium glycocholate) can significantly increase the amount of drug immobilized on the polymer; in this case, a clear pattern was revealed between the amount of introduced hydrophobic counterion and the degree of inclusion of MOX. To impart stability to the system, it is necessary to add water-soluble polymer stabilizers of the emulsion, the chemical nature of which can also affect the efficiency of sorption. The optimal value of M.M. such stabilizers - it should not exceed 70 kDa.

As a result of studying the process of the rate of drug release from polymer nanoparticles, it was found that by changing M.M. polymer, you can adjust both the speed and duration of the release of the antibiotic from the polymer. As a result of the studies, it was found that the therapeutic effect is achieved using PLA and copolymers of PGA, with MM from 5 to 300 kDa. The size of polymer nanoparticles should not exceed 1000 nm, but too small particles - less than 50 nm - are undesirable, because, having a high specific surface, such nanoparticles release the drug substance too quickly. The increase in the content of the active ingredient in the tool in excess of 10 wt.% Does not lead to an increase in the effectiveness of the treatment. The claimed ratio of components in the tool are optimal. It was experimentally established that due to the immobilization of the antibiotic in the nanoparticles of a biodegradable polymer, the efficiency of drug delivery directly to macrophages increases.

The proposed antibacterial agent is prepared as follows.

The known method of manufacturing either a simple emulsion: water / oil, or a complex (double) emulsion: water / oil / water by single or multiple homogenization of the organic and aqueous phases containing the components of the claimed means, followed by evaporation of the organic solvent, produce nanoparticles from PLA or copolymers of PLGA 100-800 nm in size. Sorption of MOX inside polymer nanoparticles is carried out during the formation of a suspension of nanoparticles by removing the organic solvent from the emulsion. The double emulsion method has certain advantages for certain types of medicinal substances. However, as our experiments showed (see control examples 1 and 2), in the case of MOX, it is preferable to use a technologically simpler method of simple emulsions using a hydrophobic counterion, although the double emulsion method is also acceptable in the case of low concentrations of the counterion.

The invention is illustrated by the following examples.

I. Obtaining polymer nanoparticles with MOXs included in them.

Example 1. (control - without the addition of a hydrophobic counterion)

Obtaining nanoparticles by the double emulsion method.

A system consisting of a 5-20% solution of a polymer / polymers of lactic acid and / or a copolymer / copolymers of lactic and glycolic acids in an organic solvent (usually methylene chloride or chloroform) and a 0.5-5% aqueous solution of moxifloxacin hydrochloride (MOX · HCl) , the volume ratio of organic and aqueous phases 3: 2, homogenize to obtain a primary emulsion. The resulting primary emulsion is mixed with a 0.5-5% aqueous solution of the polymer stabilizer of the emulsion in a volume ratio of 1: 5 and homogenized again. The resulting complex emulsion is stirred for 3 hours until the organic solvent is completely removed or the organic solvent is removed by evaporation under reduced pressure using a rotary evaporator. The resulting suspension is filtered, add 1-10 wt.% Filler-cryoprotectant (glucose, mannitol, lactose, trehalose) and lyophilized. The average particle size is 100-800 nm, depending on the homogenization conditions and the emulsion stabilizer and surfactant used. The degree of inclusion of MOX is 20-40%.

Example 2. (control - without the addition of a hydrophobic counterion)

Obtaining nanoparticles by the method of simple emulsions.

A system consisting of a 2-20% solution of a polymer / polymers of lactic acid and / or a copolymer / copolymers of lactic and glycolic acids in an organic solvent (usually in methylene chloride or chloroform) and a 0.5-5% solution of MOX · HCl in 0.5- 5% aqueous solution of the polymer stabilizer of the emulsion, the volume ratio of the organic and aqueous phases 1: 5, homogenize to obtain an emulsion. The resulting emulsion is further processed as described in Example 1. The average particle size is 100-800 nm (depending on the homogenization conditions and the emulsion stabilizer used). The degree of inclusion of MOX is 20-40%.

Example 3. Obtaining nanoparticles by the method of simple emulsions.

A system consisting of 2-20% polymer / polymers of lactic acid and / or copolymer / copolymers of lactic and glycolic acids and 0.5-5% hydrophobic counterion in an organic solvent (usually chloroform) and a 0.5-5% MOX solution HCl in a 0.5-5% aqueous solution of a polymer stabilizer of the emulsion, the volume ratio of organic and aqueous phases is 1: 5, homogenized to obtain an emulsion. The organic solvent from the resulting emulsion is removed by evaporation under reduced pressure using a rotary evaporator. The resulting suspension is filtered, add 1-10 wt.% Filler-cryoprotectant (glucose, mannitol, lactose, trehalose) and lyophilized. The average particle size is 100-800 nm, depending on the homogenization conditions and the emulsion stabilizer used. The degree of inclusion of MOX is 50-100%.

Example 4. Obtaining nanoparticles by the method of double emulsions.

A system consisting of 5-20% polymer / polymers of lactic acid and / or copolymer / copolymers of lactic and glycolic acids and 0.01-0.5% hydrophobic counterion in an organic solvent (usually chloroform) and 0.5-5% aqueous MOX · HCl solution, the volume ratio of organic and aqueous phases 3: 2, homogenized to obtain a primary emulsion. The resulting primary emulsion is mixed with a 0.5-5% aqueous solution of the polymer stabilizer of the emulsion in a volume ratio of 1: 5 and homogenized again. The organic solvent from the resulting complex emulsion is removed by evaporation under reduced pressure using a rotary evaporator. The resulting suspension is filtered, add 1-10 wt.% Filler-cryoprotectant (glucose, mannitol, lactose, trehalose) and lyophilized. The average particle size is 100-800 nm, depending on the homogenization conditions and the emulsion stabilizer and surfactant used. The degree of inclusion of MOX is 40-70%.

The compositions of the proposed antibacterial agents obtained in examples 3 or 4, in wt.%.

Composition 1. (as in example 3) PLA, M.M. 42 kDa, average particle size 400 nm 14.1 Moxifloxacin 1.4 Potassium cholesteryl sulfate 1.4 Serum Albumin, M.M. 6-10 kDa 16 Glucose 67.1 Composition 2 (as in example 4). PLA-COOH, M.M. 16 kDa, average particle size 100 nm 10 Moxifloxacin one Sodium glycocholate 0.1 Polyvinylpyrrolidone, M.M. 30-60 kDa twenty Attracts 68.9 Composition 3 (as in example 4). PLA, M.M. 42 kDa, average particle size 200 nm 24 Moxifloxacin 2,4 Potassium cholesteryl sulfate 0.01 Polyvinyl alcohol, M.M. 30-70 kDa 12,2 Mannitol 61.39 Composition 4 (as in example 4). The copolymer PLGA 75/25, M.M. 90-126 kDa, average particle size 220 nm 39 Moxifloxacin 3.9 Potassium cholesteryl sulfate 0.1 Polyvinyl alcohol, M.M. 30-70 kDa fifteen Glucose 42 Composition 5 (as in example 3). A mixture of PLA, M.M. 300 kDa and copolymer PLGA 50/50, M.M. 60 kDa (2: 1), average particle size 800 nm 40 Moxifloxacin 5 Potassium cholesteryl sulfate 5 Poloxamer 407 twenty Trehalose thirty Composition 6 (as in example 3). A mixture of PLA, M.M. 5 kDa and PLA, M.M. 42 kDa (1: 1), average particle size 500 nm 25 Moxifloxacin 1,1 Sodium glycocholate 1,5 Poloxamine 908 5 Lactose 67.4 Composition 7 (according to example 3) with the addition of water PLA, M.M. 42 kDa, average particle size 250 nm 10.0 Moxifloxacin 2.1 Potassium cholesteryl sulfate 0.9 Polyvinyl alcohol, M.M. 30-70 kDa 5,0 Glucose 1,0 Water 81.0.

II. A study of the effectiveness of the proposed antibacterial agents.

1) The effectiveness of the delivery of moxifloxacin into the intracellular medium in vitro. To establish the efficiency of delivery of MOXs with the proposed nanosomal preparation to macrophages infected with Mycobacterium tuberculosis, we used the obtained composition 3. For this, differentiated macrophages of THP-1 (monolayer) infected with a suspension of M. tuberculosis (H37Rv) containing 1 ml of 2.5 × 10 ⁶ colony forming units (CFU / ml) were incubated at 37 ° C with a nanosomal preparation (composition 3) and the control with a solution of free MOX. The cells were separated from the extracellular medium after incubation by filtration through Millipore SM membrane filters with a pore diameter of 5 μm. The concentration of MOX in the cell lysate and filtrate was determined by ELISA. Upon incubation of cells with free MOX, the equilibrium intracellular concentration of MOX is reached within 5 min and equals 131 ± 12 μg / ml, while upon incubation of cells with immobilized MOX, the equilibrium intracellular concentration of MOX continues to increase for 1 hour and reaches higher values - 373 ± 32 μg / ml - see figa, which shows comparative data on the accumulation of free and nanosomal MOX. When cells are incubated with nanosomal MOX, antibiotic release to the medium continues for 24-48 hours.

As can be seen from the data on the intracellular accumulation of MOX, the proposed nanosomal preparation accumulates more efficiently in macrophages and remains there for a longer time than free MOX. These results indicate the great potential of such a drug delivery system for the treatment of intracellular infections, since infected macrophages are able to accumulate nanoparticles in large quantities.

2) Determination of the antibacterial activity of the proposed nanosomal agent against intracellular bacteria.

To evaluate the activity of MOX associated with polymer nanoparticles (composition 3), against intracellular bacteria, differentiated THP-1 macrophages (monolayer) were infected with a suspension of M. tuberculosis (H37Rv) containing 2.5 × 10 ⁶ CFU / ml. After 1 hour, cells were washed to remove non-internalized bacteria and cultured for 24 hours. Then on Wednesday, twice with an interval of 2 hours was added the proposed drug (composition 3) containing MOX at concentrations of 0.1, 1.0 and 10.0 μg / ml. Counting viable bacteria (CFU / ml) was carried out by serial dilutions of cell lysates and their subsequent cultivation for 4 or 8 days. Antibacterial activity was evaluated by the change in the number of viable cells in the samples after incubation of a suspension of cells with an immobilized antibiotic. As control was used free MOX in the same concentrations.

The results of comparing the activity of immobilized and free MOX are shown in Fig.1b. As can be seen from fig.1b, the antimicrobial effect of nanosomal MOX was significantly higher compared to the free antibiotic. So, after 4 days, for a concentration of MOX of 10 μg / ml, the number of colony forming units for free MOX was 1.5 × 10 ⁴ CFU / ml, and for nanosomal, 6.2 × 10 ³ CFU / ml. In addition, nanosomal MOX was retained for a long time inside the cells, secreted for 48 hours, which indicates the prolongation of the action of MOX (depot effect) associated with nanoparticles, compared with free MOX.

3) The effectiveness of the proposed antibacterial agents for the treatment of experimental tuberculosis in mice.

The study of the chemotherapeutic activity of MOXC, associated with polymer nanoparticles - composition 4, was performed on mice with experimental tuberculosis. Female BALB / c mice (7-8 weeks old) were infected by intravenous administration of Mycobacterium tuberculosis H37Rv at a dose of 5 × 10 ⁶ -10 ⁷ colony forming units (CFU) per mouse. Infected mice were divided into three groups (n = 10). The animals in group 1 were injected with nanosomal MOX (Moxy / PLGA). For this, 2.5 ml of water for injection was added to 200 mg of nanosomal MOX (composition 4). The resulting colloidal system was administered to mice at a dose of 10 mg / kg MOX intravenously three times: on the fourth, fifth and sixth day after infection. The control animals were injected with the substance of free MOX (Moxy) in the same therapeutic doses. As an additional control, animals that were not treated were used (Control). A day after the completion of the 3-day course of therapy, the infected animals were euthanized, the lung (right) was isolated and homogenized under aseptic conditions, and then they were plated on plates with 7H11 medium. Counting live mycobacteria in units of CFU was performed after 3-4 weeks. The results are shown in figure 2.

As can be seen from figure 2, in experimental tuberculosis in mice, the nanosomal drug (Moxi / PLGA, composition 4) exhibits a higher antibacterial effect compared to the standard substance (Moxi), that is, it allows to increase the effectiveness of treatment.

4) The effectiveness of the proposed antibacterial agents for the treatment of experimental septic infections in mice.

The study of the chemotherapeutic activity of MOX associated with polymer nanoparticles - composition 1 (Moxi-PLA) was carried out in mice with experimental septic infection caused by the introduction of E. coli.

The study used female BALB / c mice aged 6-8 weeks (n = 10). The mice were kept in micro isolators and received water and food ad libitum. After one-week quarantine, mice were infected with E. coli (strain 0157). A suspension of bacteria was administered intraperitoneally at a dose of 2.5 × 10 CFU in 0.1 ml of physiological saline.

MOX preparations (Moxy-PLA and free MOX - Moxy) were administered intravenously at a dose of 1 × 25 mg / kg (according to MOX) 4 hours after infection. The results are shown in figure 3. It can be seen that treatment with nanosomal MOX (Moxy-PLA) led to the survival of 60% of the animals, while with the administration of the free antibiotic (Moxy) only 20% survived. In the control, all animals died.

Thus, the results show that the proposed antibacterial agent for the treatment of intracellular infections provides the maximum manifestation of the positive characteristics inherent to moxifloxacin, since it allows the targeted delivery of the antibiotic to macrophages, which during intracellular infections are a niche for the survival of pathogenic microorganisms, and also allows you to adjust the release rate of the drug substances from a polymer carrier and, therefore, provide a prolonged e effect of the antibiotic. As a result, the effectiveness of the treatment of intracellular infections, in particular tuberculosis and septic infection, is increased, which suggests the possibility of reducing the used doses of the antibiotic and, therefore, toxic effects. The achieved effect of the depot of the proposed drug is also likely to overcome the resistance of tuberculosis pathogens, since it is known that mycobacteria with multiple drug resistance grow one and a half times slower than mycobacteria with preserved drug sensitivity (G.B.Sokolova, S.E. Borisov, A.D. Kunich, Ya.V. Lazareva, G.N. Mozhokina, N.A. Elistratova, A.A. Tsybanev, M.I. Perelman. Treatment of drug-resistant tuberculosis. A manual for TB doctors. Ministry of Health of the Russian Federation , Research Institute of Phthisiopulmonology MMA named after I.M.Sechenov, Moscow, 2002). In addition, the present invention avoids the technologically complex and time-consuming process of synthesizing a polymer carrier from monomers.

Claims (2)

1. An antibacterial agent for the treatment of intracellular infections based on a drug immobilized on a polymer carrier, comprising targeted additives, characterized in that it contains moxifloxacin as a drug substance, as a carrier polymer nanoparticles with a size of 100-800 nm polymer / polymers of lactic acid and / or copolymer / copolymers of lactic and glycolic acids with a glycolic acid content in said copolymers of up to 50 mol%, while the molecular weight of said polymers and copolymers imer ranges from 5 to 300 kDa, and the product further comprises potassium cholesteryl sulfate or sodium glycocholate and a water-soluble natural or synthetic polymer stabilizer with a molecular weight of not more than 70 kDa selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, poloxamer, poloxamine and serum albumin filler, in the following ratio of components, wt.%: Specified polymer carrier 10-40 Moxifloxacin 1-5 Potassium cholesteryl sulfate or sodium glycocholate 0.01-5 The specified polymer stabilizer 5-20 Filler rest 2. The antibacterial agent according to claim 1, characterized in that it further comprises a solvent - water or aqueous mixtures in an amount of not less than 80 wt.%.

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