Antimicrobial combination

Abstract

The present invention provides an antimicrobial combination comprising three different antimicrobial agents. The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof; the second antimicrobial agent is selected from the group consisting of zidovudine, doxycycline and pharmaceutically acceptable derivatives thereof; and the third antimicrobial agent is selected from the group consisting of fosfomycin, levofloxacin, polymyxin E, polymyxin B and pharmaceutically acceptable derivatives thereof, with the proviso that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

Description

Technical Field

[0001] This invention relates to a synergistic combination of three antimicrobial agents. The first, second, and third agents are selected from the corresponding groups as defined herein, and the combination has a synergistic effect against Gram-negative and / or Gram-positive bacteria, meaning it is suitable for treating microbial infections caused by said bacteria. In particular, this invention relates to the use of such a combination to kill proliferating (i.e., logarithmic phase) microorganisms associated with bacterial infections (e.g., Gram-negative bacterial infections). Background Technology

[0002] Before the advent of antibiotics, patients with acute microbial infections, such as tuberculosis or pneumonia, had a low survival rate. For example, the mortality rate for tuberculosis was approximately 50%. The emergence of antimicrobial agents in the 1940s and 50s rapidly changed this, and now there are approximately 100 antibiotics available to treat various bacterial infections. This has enabled modern medicine, as bacterial infections can be effectively prevented and treated in millions of patients with conditions such as cancer, organ transplants, kidney dialysis, immunosuppression, and surgery.

[0003] However, the response of bacteria to the widespread use of antibiotics is the gradual acquisition of resistance. Now, every country in the world has antibiotic-resistant bacteria, and this resistance is increasing every year, thus reducing the effectiveness of all antibiotics. By 2040–2050, the number of deaths from antimicrobial resistant infections is projected to exceed 10 million per year (The Review on Antimicrobial Resistance, chaired by Jim O'Neill, May 2016).

[0004] The rise of antimicrobial resistance is projected to occur in poorer countries by 2040–2050, and is already a real, tangible medical problem in Europe and the United States. In fact, in the United States, over 70% of bacteria causing hospital-acquired infections are resistant to at least one major antimicrobial agent commonly used to treat infections (Nature Reviews, DrugDiscovery, 1, 895–910 (2002)). Consequently, the World Health Organization (WHO) has listed antimicrobial resistance as “a serious threat, [that] is no longer a prediction of the future, but is now occurring in every region of the world and has the potential to affect anyone, in any country, at any age” (“Antimicrobial resistance: global report on surveillance”, WHO, April 2014). If this problem is not addressed, life expectancy could revert to pre-antibiotic levels, approximately 20 years less than it is now.

[0005] Therefore, there is an urgent need for a solution to the growing problem of antimicrobial resistant bacteria. Essentially, the medical field needs to replace approximately 100 antibiotics with products that can effectively combat antimicrobial resistant infections while preventing the development of future antimicrobial resistance.

[0006] Current efforts to address this problem primarily focus on developing new chemical entities (or NCEs). Each NCE requires over 10 years of research and development time and costs over $600 million to complete the necessary safety and clinical trials. Due to numerous failures, it typically takes around $3.8 billion to develop an NCE antibiotic. Ironically, as antibiotic use increases, antimicrobial resistance develops even faster, meaning all NCEs have a limited lifespan, typically less than 10 years. Therefore, replacing currently used antibiotics with NCEs would require approximately $3.8 trillion over 10 years, and even if successful, these products would require ongoing planned updates and replacements within their 10-year lifespan as each product develops antimicrobial resistance. This is clearly unsustainable, even for high-income countries.

[0007] The applicant has found a solution to this significant global problem. Specifically, a combination of three or more known antibiotics has been surprisingly identified as having a synergistic effect against Gram-negative and / or Gram-positive bacteria. This combination has been found to synergistically kill multiple species, including antimicrobial-resistant bacteria (also known as drug-resistant bacteria), thereby preventing the development of antimicrobial resistance. The three or more known antibiotics are defined in the appended claims and described herein.

[0008] The demonstrated synergistic effect means that the combination has higher biological activity at the stated dose level than the expected additive effect of each agent. This implies that in combination therapy, lower doses of antibiotics (e.g., antibiotics reduced by 5 to 20 times) are more effective than any single antibiotic.

[0009] Furthermore, by combining already approved drugs (CADs), the approval process and associated costs are significantly less than for NCEs. For example, the approval time is approximately 5 years, and producing a new product costs no more than $50 million. Due to far fewer failures in development, the cumulative cost of a successful / failed CAD is approximately $130 million, compared to $3.8 billion for each NCE. The number of combinations required to replace the approximately 100 single antibiotics currently in use can be reduced because CADs are active against a wide range of different infectious species and can reactivate single antibiotics in CADs that are unusable due to antimicrobial resistance, giving them greater activity against these resistant strains and preventing the further development of antimicrobial resistance in the future. In terms of GDP share, CAD technology reduces the 4% GDP contribution of NCEs in high-income countries to approximately 0.005% GDP, enabling all high-, middle-, and even low-income countries to participate and benefit.

[0010] Currently, the world focuses solely on repetitive NCE projects, which are far more costly, time-consuming, and prone to failure, with short lifespans. Effective antibiotics are predicted to be exhausted within twenty years, and the death of antimicrobial resistance will set us back 200 years. Investing just 0.1% of NCE R&D costs in a CAD (Cardiology-based Antibiotics) approach could provide a practical, affordable, and more durable solution, offering a realistic option for continuing to provide available antibiotic products that are globally effective and affordable, thus bringing hope for “affordable antibiotics for all, forever.”

[0011] For the past decade, the applicant (a small UK company and a nonprofit organization (GARDP)) has been actively developing CAD-antibiotic combinations of existing drugs. In this application, the applicant has developed a novel approach to replace all antibiotics by discovering a synergistic combination of three antimicrobial agents. This combination is active against at least extended-spectrum β-lactamase (ESBL), carbapenem-producing (CPE), and carbapenem-resistant (CRE) Gram-negative bacteria. For example, the combination is active against *Pseudomonas aeruginosa* and *Acinetobacter baumanii*, both of which exhibit multi-resistance, such as against ceftazidime, colistin, fosfomycin, and / or meropenem. Furthermore, the combination is active against Gram-positive bacteria, including methicillin-resistant *Staphylococcus aureus* (MRSA). Even more surprisingly, the applicant has revealed that each antimicrobial agent in the combination is active at very low concentrations, such as as low as the MIC of the agent. 单 1 / 32. Therefore, by using a lower amount of each antimicrobial agent in the combination than, for example, a single therapy, any potential toxicity burden can be advantageously reduced.

[0012] WO2015 / 114340 describes the use of zidovudine in combination with a polymyxin selected from colistin or polymyxin B, an antituberculosis antibiotic selected from rifampin, rifapentine, or rifabutin, and optionally piperine, for the treatment of microbial infections. WO2018 / 011562 describes a combination comprising zidovudine and carbapenem, optionally combined with a polymyxin selected from polymyxin B and polymyxin E. Therefore, this invention does not include these previously identified combinations by the applicant.

[0013] When two or more active substances are used in combination, synergistic effects are not predictable or expected. In the context of antimicrobial drugs, synergistic effects are measured in several ways that conform to the generally accepted view that "synergistic effect is an effect greater than additive." One method for assessing whether synergistic effects are observed is the use of the "chessboard" technique. This is a widely accepted method that produces a value called the Fiscal Inhibition Concentration Index (FICI). Orhan et al., J. Clin. Microbiol. 2005, 43(1):140, describe the chessboard method and analysis in paragraphs spanning pages 140-141.

[0014] The FICI, or graded inhibitory concentration index, is the sum of the FICs of each antimicrobial agent when used in combination. The FIC or graded inhibitory concentration of the antimicrobial agents in a combination is the MIC of the antimicrobial agents in the combination divided by the MIC of the same antimicrobial agent used alone. The minimum inhibitory concentration is defined in the art as the lowest concentration of antimicrobial agent that inhibits visible microbial growth after overnight incubation.

[0015] The combinations exhibit activity against Gram-positive and Gram-negative bacteria, including resistant bacteria (see examples herein). Individual antimicrobial agents in these combinations often exhibit significant activity at concentrations significantly lower than their MICs when used alone. However, there appears to be no method in the art to define the synergistic effect of 3-mer combinations (combinations of three antimicrobial agents) expressed as graded inhibitory concentrations. In fact, prior work in this area is scarce. Therefore, the inventors have devised such a method. This method is applicable to any combination of two or more antimicrobial agents, provided that only the concentrations of the two antimicrobial agents differ.

[0016] In the 3-mer combination approach, one antibiotic is "fixed" as part of a backbone, while the concentrations of the other two antibiotics vary in a doubling manner, starting from the MIC (x1), which is the effective dose against the test organism in a single therapy. The ΣFIC is calculated as follows.

[0017] The FIC is obtained by dividing ΣFIC by "0.5 / n", where n = the number of antimicrobial agents in the combination. The inventors chose this expression because it is closer to the synergistic effect level of 2-mer. The same FIC scale used for 2-mer was applied: synergism was observed when FIC < 0.5. An "additive" effect was observed when FIC was 0.5 to < 1. No difference was observed when FIC was 1 to < 2. Antagonism was observed when FIC was 2 to 4.

[0018] The synergistic effect can be expressed as "ΣFIC ≤ 0.25 xn".

[0019] The above method was used in the embodiments described herein. Summary of the Invention

[0020] On one hand, the present invention provides an antimicrobial combination comprising three antimicrobial agents, wherein (i) the first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof, (ii) the second antimicrobial agent is selected from zidovudine, doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) the third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B or a pharmaceutically acceptable derivative thereof, provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

[0021] On the other hand, the present invention provides a combination for treating infections caused by Gram-negative or Gram-positive bacteria.

[0022] On the other hand, the present invention provides a pharmaceutical composition comprising a combination as defined herein and a pharmaceutically acceptable adjuvant, diluent, or carrier. The pharmaceutical composition is preferably used to treat infections caused by Gram-negative or Gram-positive bacteria.

[0023] On the other hand, the present invention provides a product comprising an antimicrobial combination of three antimicrobial agents, wherein: the first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof; the second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof; and the third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof; provided that the combination, as a combined preparation used simultaneously, separately, or sequentially, is for treating infections caused by Gram-negative or Gram-positive bacteria. Preferably, the second antimicrobial agent is zidovudine or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, polymyxin E, polymyxin E, and pharmaceutically acceptable derivatives thereof. More preferably, the third antimicrobial agent is selected from fosfomycin, polymyxin E, and pharmaceutically acceptable derivatives thereof. In an alternative preferred embodiment, the second antimicrobial agent is doxycycline or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, levofloxacin, and pharmaceutically acceptable derivatives thereof.

[0024] In another aspect, the present invention provides the use of a first antimicrobial agent in combination with at least a second and a third antimicrobial agent in the preparation of a medicament for synergistic treatment of Gram-negative or Gram-positive bacterial infections. The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof. The second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof. The third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof; provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

[0025] In another aspect, the present invention provides the use of a second antimicrobial agent in combination with at least a first and a third antimicrobial agent in the preparation of a medicament for synergistic treatment of Gram-negative or Gram-positive bacterial infections. The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof. The second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof. The third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof; provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

[0026] In another aspect, the present invention provides the use of a third antimicrobial agent in combination with at least the first and second antimicrobial agents in the preparation of a medicament for synergistic treatment of Gram-negative or Gram-positive bacterial infections. The first antimicrobial agent is selected from meropenem or a pharmaceutically acceptable derivative thereof. The second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof. The third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof; provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

[0027] On the other hand, the present invention provides a method for treating Gram-negative or Gram-positive bacterial infections, wherein the method comprises administering a pharmaceutically effective amount of a combination of three antimicrobial agents, wherein the first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof; the second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof; and the third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof, provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

[0028] These aspects and their embodiments are set forth in the appended independent and dependent claims. It should be understood that the features of the dependent claims may be combined with each other and with features of the independent claims in other combinations not expressly specified in the claims. Furthermore, this disclosure is not limited to the specific embodiments set forth below, but includes and contemplates any combination of the features described herein.

[0029] The foregoing and other aspects, embodiments, features, and advantages of this disclosure will become apparent from the detailed description below. In this regard, certain portions of the specification should not be read in isolation from the other portions. Detailed Implementation

[0030] While various exemplary embodiments are described or suggested herein, other exemplary embodiments utilizing methods and materials similar to or equivalent to those described or suggested herein are also included within the overall conception of the invention. Features or embodiments implemented in a conventional manner may not be discussed or described in detail for the sake of brevity. Therefore, it should be understood that features of devices, products, or processes not described in detail herein can be implemented using any conventional techniques used to implement such features in the appropriate context.

[0031] As used herein, the expressions “combination of…” and “in combination with…” cover the administration of the agents alone, sequentially, and simultaneously. Unless otherwise stated, these expressions are also intended to exclude any additional active substances, such as “synergistic combination of three antimicrobial agents” which means that the defined antimicrobial agents are administered alone, sequentially, or simultaneously, but no other active substance, i.e., antimicrobial agent, is administered.

[0032] When the agents are applied sequentially, the first, second, or third antimicrobial agent may be applied first. When applied simultaneously, the agents may be applied in the same or different pharmaceutical compositions. In a preferred embodiment, the agents are applied sequentially or simultaneously.

[0033] The combinations of the present invention can be used to treat Gram-positive or Gram-negative bacterial infections. In particular, they can be used to kill proliferating bacteria and / or clinically latent bacteria associated with such infections, preferably killing proliferating bacteria associated with such infections, such as proliferating bacteria associated with Gram-negative bacterial infections. Therefore, the treatment of bacterial infections mentioned herein includes killing proliferating microorganisms and / or clinically latent microorganisms associated with such infections.

[0034] As used in this article, “killing” refers to the loss of vitality as assessed by a lack of metabolic activity.

[0035] As used in this article, "clinically latent bacteria" refers to metabolically active bacteria whose growth rate is below the infectious disease expression threshold. The infectious disease expression threshold refers to the growth rate threshold; below this threshold, no infectious disease symptoms are present in the host.

[0036] The metabolic activity of clinically latent bacteria can be determined by a variety of methods known to those skilled in the art; for example, by measuring mRNA levels in the bacteria or by determining their uridine uptake rates. In this regard, clinically latent bacteria exhibit reduced but still significant levels of the following when compared to bacteria under logarithmic growth conditions (in vitro or in vivo): (I) mRNA (e.g., 0.0001 to 50%, such as 1 to 30%, 5 to 25%, or 10 to 20% mRNA levels); and / or (II) Uroside (e.g., [3H]uridine) uptake (e.g., 0.0005 to 50%, such as 1 to 40%, 15 to 35%, or 20 to 30% of [3H]uridine uptake levels).

[0037] Clinically latent bacteria typically possess several identifiable characteristics. For example, they may be viable but unculturable; that is, they are generally undetectable by standard culture techniques but can be detected and quantified using techniques such as broth dilution counting, microscopy, or molecular techniques (such as polymerase chain reaction). Furthermore, clinically latent bacteria are phenotypic resistant and therefore (in the logarithmic phase) sensitive to the bioinhibitory effects of conventional antimicrobials (i.e., for this bacterium, the minimum inhibitory concentration (MIC) of a conventional antimicrobial agent remains essentially unchanged); however, they are significantly less sensitive to drug-induced killing (e.g., for this bacterium, the ratio of the minimum bactericidal concentration (e.g., the minimum bactericidal concentration, MBC) to the MIC is 10 or higher for any given conventional antimicrobial agent).

[0038] In various embodiments of the invention, one or more of the above combinations are used to treat bacterial infections, particularly the combinations being used to kill proliferating bacteria and / or clinically latent bacteria associated with the bacterial infection. As used herein, the term "bacteria" (and its derivatives, such as "bacterial infection") includes, but is not limited to, the following categories and specific types of organisms (or infections caused by organisms):

[0039] Gram-positive cocci, such as staphylococci (e.g., *Staphylococcus aureus*, *Staphylococcus epidermidis*, *Staphylococcus saprophyticus*, *Staphylococcus auricularis*, *Staphylococcus capitis*, *Staphylococcus c. ureolyticus*, *Staphylococcus caprae*, *Staphylococcus cohnii cohnii*, *Staphylococcus c. urealyticus*, *Staphylococcus equorum*, *Staphylococcus gallinarum*, *Staphylococcus haemolyticus*, and *Staphylococcus hominis*). Staphylococcus hominis), Staphylococcus h. novobiosepticius, Staphylococcus hyicus, Staphylococcus intermedius, Staphylococcus lugdunensis, Staphylococcus pasteuri, Staphylococcus saccharolyticus, Staphylococcus schleiferi schleiferi, Staphylococcus s. coagulans, Staphylococcus sciuri, Staphylococcus simulans, Staphylococcus warneri, and Staphylococcus xylosus; Streptococci (e.g., β-hemolytic pyogenic streptococci, such as Streptococcus agalactiae). Streptococcus agalactiae, Streptococcus canis, Streptococcus dysgalactiae dysgalactiae, Streptococcus dysgalactiae equisimilis, Streptococcus equi equi, Streptococcus equizooepidemicus, Streptococcus iniae, Streptococcus porcinus, and Streptococcus pyogenes.pyogenes), micro-oxidative pyogenic streptococci ("Miller" streptococci, such as *Streptococcus anginosus*, *Streptococcus constellatus*, *Streptococcus constellatus*, *Streptococcus constellatus*, and *Streptococcus intermedius*), "mild" oral streptococci (α-hemolytic), "green" streptococci (*Streptococcus viridans*, such as *Streptococcus mitis*, *Streptococcus oralis*, *Streptococcus sanguinis*, *Streptococcus cristatus*, *Streptococcus gordonii*, and *Streptococcus parasanguinis*), and "salivary" streptococci (non-hemolytic, such as *Streptococcus salivaris*). Streptococci (salivarius) and vestibular streptococci (Streptococci vestibularis) and "mutant" streptococci (dental surface streptococci, such as Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, and Streptococcus sobrinus, Streptococcus acidominimus, Streptococcus bovis, Streptococcus faecalis, Streptococcus equinus, Streptococcus pneumoniae, and Streptococcus suis).Streptococci (or streptococci that can be classified into groups A, B, C, D, E, G, L, P, U, or V); enterococci (e.g., *Enterococcus avium*, *Enterococcus casseliflavus*, *Enterococcus cecorum*, *Enterococcus dispar*, *Enterococcus durans*, *Enterococcus faecalis*, *Enterococcus faecium*, *Enterococcus flavescens*, *Enterococcus gallinarum*, *Enterococcus hirae*, *Enterococcus malodoratus*, *Enterococcus montelukas*). *Enterococcus mundtii*, *Enterococcus pseudoavium*, *Enterococcus raffinosus*, and *Enterococcus solitarius*; Bacillusaceae, such as *Bacillus anthracis*, *Bacillus subtilis*, *Bacillus thuringiensis*, *Bacillus stearothermophilus*, and *Bacillus cereus*.

[0040] Gram-negative cocci, such as Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria cinerea, Neisseria elongata, Neisseria flavescens, Neisseria lactamica, Neisseria mucosa, Neisseria sicca, Neisseria subflava, and Neisseria weaveri. Enterobacteriaceae, such as *Escherichia coli*, *Enterobacter* (e.g., *Enterobacter aerogenes*, *Enterobacter agglomerans*, and *Enterobacter cloacae*), *Citrobacter* (e.g., *Citrob. freundii* and *Citrob. divernis*), *Hafnia* (e.g., *Hafnia alvei*), *Erwinia* (e.g., *Erwinia persicinus*), *Morganella* (e.g., *Morganella morganii*), *Salmonella* (*Salmonella enterica* and *Salmonella typhi*), and *Shigella* (e.g., *Shigella dysenteriae* and *Shigella freundii*). *Klebsiella flexneri*, *Shigella boydii*, and *Shigella sonnei*, and *Klebsiella* species (e.g., *Klebsiella pneumoniae*, *Klebsiella oxytoca*, *Klebsiella ornitholytica*, *Klebsiella planticola*, *Klebsiella ozaenae*, *Klebsiella terrigena*, *Klebsiella granulomatis*, *Calymmatobacterium*).The following bacteria are listed: *Klebsiella granulomatis* and *Klebs. rhinoscleromatis*; *Proteus* spp. (e.g., *Proteus mirabilis*, *Proteus rettgeri*, and *Proteus vulgaris*); *Providencia* spp. (e.g., *Providencia alcalifaciens*, *Providencia rettgeri*, and *Providencia stuartii*); *Serratia* spp. (e.g., *Serratia marcescens* and *Serratia liquifaciens*); and *Yersinia* spp. (e.g., *Yersinia enterocolitica*, *Yersinia pestis*, and *Yersinia pseudotuberculosis*). pseudotuberculosis); Helicobacter spp. (e.g., Helicobacter pylori, Helicobacter cinaedi, and Helicobacter fennelliae); Acinetobacter spp. (e.g., Acinetobacter baumanii, Acinetobacter calcoaceticus, Acinetobacter haemolyticus, Acinetobacter johnsonii, Acinetobacter junii, Acinetobacter lwoffi, and Acinetobacter radionoresistens); Pseudomonas spp. (e.g., Ps. aeruginosa, Ps. maltophilia, Stenotrophomonas maltophilia, Ps. alcaligenes, and Ps. velutipes). *Pseudomonas chlororaphis*, *Ps. fluorescens*, *Ps. luteola*, *Ps. mendocina*, *Ps. monteilii*, *Ps. oryzihabitans*, *Ps. pertocinogena*, *Ps. pseudalcaligenes*, *Ps. putida*, and *Ps. schrenckii*.*Peptococcus stutzeri*); *Bacteriodes fragilis*; *Peptococcus* (e.g., *Peptococcus niger*); *Streptococcus*; *Clostridium* (e.g., *C. perfringens*, *C. difficile*, *C. botulinum*, *C. tetani*, *C. absonum*, *C. argentinense*, *C. baratii*, *C. bifermentans*, *C. beijerinckii*, *C. butyricum*, *C. cadaveris*, *C. carnis*, *C. celatum*, *C. clostridioforme*, *C. cochlearium*, *C. spirochetes*). Clostridium cocleatum, Clostridium fallax, Clostridium ghonii, Clostridium glycolicum, Clostridium haemolyticum, Clostridium hastiforme, Clostridium histolyticum, Clostridium indolis, Clostridium innocuum, Clostridium irregulare, Clostridium leptum, Clostridium limosum, Clostridium malenominatum, Clostridium novyi, Clostridium oroticum, Clostridium paraputrificum, Clostridium piliforme, Clostridium putrefasciens, Clostridium ramosum, Clostridium septicum. Clostridium septicum, Clostridium sordelii, Clostridium sphenoides, Clostridium sporogenes, Clostridium subterminale, Clostridium symbiosum, and Clostridium tertium); Mycoplasma species (e.g., Mycoplasma pneumoniae, Mycoplasma hominis, Mycoplasma genitalium, and Ureaplasma urealyticum).Mycobacteria (e.g., Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium marinum, Mycobacterium kansasii, Mycobacterium chelonae, Mycobacterium abscessus, Mycobacterium leprae, Mycobacterium smegmitis, Mycobacterium africanum, Mycobacterium alvei, Mycobacterium asiaticum, Mycobacterium aurum, Mycobacterium bohemianum) Mycobacterium bovis, Mycobacterium branderi, Mycobacterium brumae, Mycobacterium celatum, Mycobacterium chubense, Mycobacterium confluentis, Mycobacterium conspicuum, Mycobacterium cookii, Mycobacterium flavescens, Mycobacterium gadium, Mycobacterium gastri, Mycobacterium genavense, Mycobacterium gordonae, Mycobacterium goodii, Mycobacterium haemolyticum Mycobacterium haemophilum, Mycobacterium hassicum, Mycobacterium intracellulare, Mycobacterium medulansMycobacterium interjectum, Mycobacterium heidelberense, Mycobacterium lentiflavum, Mycobacterium malmoense, Mycobacterium microgenicum, Mycobacterium microti, Mycobacterium mucogenicum, Mycobacterium neoaurum, Mycobacterium nonchromogenicum, Mycobacterium peregrinum, Mycobacterium phlei, Mycobacterium scrofulaceum, Mycobacterium shimoidei, Mycobacterium simiae, Mycobacterium simiae Mycobacterium szulgai, Mycobacterium terrae, Mycobacterium thermoresistabile, Mycobacterium triplex, Mycobacterium triviale, Mycobacterium tusciae, Mycobacterium ulcerans, Mycobacterium vaccae, Mycobacterium wolinskyi, and Mycobacterium xenopi; Haemophilus species (e.g., Haemophilus influenzae, Haemophilus ducreyi, Haemophilus aegyptius, Haemophilus parainfluenzae, Haemophilus hemolyticus).Haemophilus parahaemolyticus and Haemophilus parahaemolyticus; Actinobacteria (e.g., Actinobacillus actinomycetemcomitans, Actinobacillus equuli, Actinobacillus hominis, Actinobacillus lignieresii, Actinobacillus suis, and Actinobacillus ureae); Actinobacteria (e.g., Actinomyces israelii); Brucella (e.g., Brucella abortus, Brucella canis, Brucella melintensis, and Brucella suis); Campylobacter (e.g., Campylobacter jejuni). * Campylobacter jejuni*, *Campylobacter coli*, *Campylobacter lari*, and *Campylobacter fetus*; *Listeria monocytogenes*; *Vibrio* (e.g., *Vibrio cholerae*, *Vibrio parahaemolyticus*, *Vibrio alginolyticus*, *Vibrio carchariae*, *Vibrio fluvialis*, *Vibrio furnissii*, *Vibrio hollisae*, *Vibrio metschnikovii*, *Vibrio mimicus*, and *Vibrio vulnificus*); *Erysipelothrix rhusopathiae*; *Corynebacterium* (e.g., *Corynebacterium diphtheriae*). *Corynebacterium diphtheriae*, *Corynebacterium jeikeum*, and *Corynebacterium urealyticum*; spirochetal families, such as the genus *Borrelia* (e.g., *Borrelia relapsingii*).The following are listed: *Borrelia recurrentis*, *Borrelia burgdorferi*, *Borrelia afzelii*, *Borrelia andersonii*, *Borrelia bissettii*, *Borrelia garinii*, *Borrelia japonica*, *Borrelia lusitaniae*, *Borrelia tanukii*, *Borrelia turdi*, *Borrelia valaisiana*, *Borrelia caucasica*, *Borrelia crocidurae*, *Borrelia duttoni*, *Borrelia graingeri*, *Borrelia hermsii*, and *Borrelia esculenta*. The genera *Hispanica*, *Borrelia latyschewii*, *Borrelia mazzottii*, *Borrelia parkeri*, *Borrelia persica*, *Borrelia turicatae*, and *Borrelia venezuelensis*, and the genus *Treponema* (*Treponema pallidum* ssp. pallidum, *Treponema pallidum* ssp. endemicum, *Treponema pallidum* ssp. pertenue, and *Treponema carateum*); and the genus *Pasteurella* (e.g., *Pasteurella aerogenes*, *Pasteurella bettyae*, *Pasteurella canis*). Pasteurella canis, Pasteurella dagmatis, Pasteurella gallinarum, Pasteurella haemolytica, Pasteurella multocida* *Pasteurella multocida*, *Pasteurella multocida gallicida*, *Pasteurella multocida septica*, *Pasteurella pneumotropica*, and *Pasteurella stomatis*; *Bordetella* genus (e.g., *Bordetella bronchitidis*, *Bordetella hinzii*, *Bordetella holmseii*, *Bordetella parapertussis*, *Bordetella pertussis*, and *Bordetella trematum*); *Nocardiaceae*, such as *Nocardia* genus (e.g., *Nocardia asteroides*). asteroides and Nocardia brasiliensis; Rickettsia (e.g., Ricksettsii or Coxiella burnetii); Legionella (e.g., Legionella anisa, Legionella birminghamensis, Legionella bozemanii, Legionella cincinnatiensis, Legionella dumoffii, Legionella feeleii, Legionella gormanii, Legionella hackeliae, Legionella israelensis, Legionella jordanis, Legionella lansingensis, Legionella longbowensis). Legionella longbeachae, Legionella maceachernii, Legionella micdadei, Legionella oakridgensis, Legionella pneumophila, Legionella helenensisLegionella sainthelensi, Legionella tucsonensis, and Legionella wadsworthii; Moraxella catarrhalis; Cyclospora cayetanensis; Entamoeba histolytica; Giardia lamblia; Trichomonas vaginalis; Toxoplasma gondii; Stenotrophomonas maltophilia; Burkholderia stenotrophomonas; Burkholderia cepacia; Burkholderia mallei and Burkholderia melioides. pseudomallei); Francisella tularensis; Gardnerella spp. (e.g., Gardneralla vaginalis and Gardneralla mobiluncus); Streptobacillus moniliformis; Flavobacteriaceae, such as Capnocytophaga spp. (e.g., Capnocytophaga canimorsus, Capnocytophaga cynodegmi, Capnocytophaga gingivalis, Capnocytophaga granulosa, Capnocytophaga haemolytica, Capnocytophaga ochracea, and Capnocytophaga sputum). sputigena); Bartonella genus (Bartonellabacilliformis, Bartonella clarridgeiae, Bartonella elizabethae, Bartonella henselae)* *Henselae*, *Bartonella quintana*, and *Bartonella vinsoniiarupensis*; *Leptospira* (e.g., *Leptospira biflexa*, *Leptospira borgpetersenii*, *Leptospira inadai*, *Leptospira interrogans*, *Leptospira kirschneri*, *Leptospira noguchii*, *Leptospira santarosai*, and *Leptospira weilii*); *Spirulina* (e.g., *Spirillum minus*); *Bacteroides* (e.g., *Bacteroides caccae*, *Bacteroides vinsoniiarupensis*). Bacteroides capillosus, Bacteroides coagulans, Bacteroides distasonis, Bacteroides eggerthii, Bacteroides forsythus, Bacteroides fragilis, Bacteroides merdae, Bacteroides ovatus, Bacteroides putredinis, Bacteroides pyogenes, Bacteroides splanchinicus, Bacteroides stercoris, Bacteroides tectus, Bacteroides thetaiotaomicron, Bacteroides uniformis, Bacteroides ureolyticus, and Bacteroides commonis. vulgatus); Prevotella spp. (e.g., Prevotella bivia, Prevotella buccae, Prevotella vulgatus)Prevotella corporis, Prevotella dentalis (Mitsuokella dentalis), Prevotella denticola, Prevotella disiens, Prevotella enoeca, Prevotella heparinolytica, Prevotella intermedia, Prevotella loeschii, Prevotella melaninogenica, Prevotella nigrescens, Prevotella oralis, Prevotella oris, Prevotella oulora, Prevotella tansii * Prevotella tannerae*, *Prevotella venoralis*, and *Prevotella zoogleoformans*; *Porphyromonas* spp. (e.g., *Porphyromonas asaccharolytica*, *Porphyromonas cangingivalis*, *Porphyromonas canoris*, *Porphyromonas cansulci*, *Porphyromonas catoniae*, *Porphyromonas circumdentaria*, *Porphyromonas screvioricanis*, *Porphyromonas endodontalis*, *Porphyromonas gingivalis*). *Porphyromonas gingivicanis*, *Porphyromonas levii*, and *Porphyromonas macacae*; *Fusobacterium* species (e.g., *F. gonadiaformans*, *F. mortiferum*, *F. nabothii*).* *Clostridium naviforme*, *F. necrogenes*, *F. necrophorum necrophorum*, *F. necrophorum fundiliforme*, *F. nucleatum nucleatum*, *F. nucleatum fusiforme*, *F. nucleatum polymorphum*, *F. nucleatum vincentii*, *F. periodonticum*, *F. russii*, *F. ulcerans*, and *F. varium*; *Chlamydia* (e.g., *Chlamydia trachomatis*); *Cryptosporidium* (e.g., *C. parvum*, *C. humanis*). Cryptosporidium hominis, Cryptosporidium canis, Cryptosporidium felis, Cryptosporidium meleagridis, and Cryptosporidium muris; Chlamydia species (e.g., Chlamydophila abortus, Chlamydia psittaci), Chlamydophila pneumoniae, and Chlamydophila psittaci); Leuconostoc species (e.g., Leuconostoc citreum, Leuconostoc cremoris, Leuconostoc dextranicum, Leuconostoc citreum). *Lactis*, *Leuconostoc mesenteroides*, and *Leuconostoc pseudomesenteroides*; *Gemella* species (e.g., *Gemella bergeri*, *Gemella haemolysans*, *Gemella morbillorum*, and *Gemella hemolyticus*).Aeromonas genus (e.g., Aeromonas hydrophila, Aeromonas caviae, and Aeromonas veronii biovar sobria); and Ureaplasma genus (e.g., Ureaplasma parvum and Ureaplasma urealyticum).

[0041] Preferably, the combination of the present invention has a synergistic effect on Gram-positive or Gram-negative bacteria selected from the following:

[0042] Gram-negative: Enterobacteriaceae, Enterobacter spp., Pseudomonas spp., Acinetobacter spp., Shigella spp., Salmonella spp., Burkholderia spp., Citrobacter spp., Serratia spp., Proteus spp., Morganella spp., Providencia spp., Haemophilus spp., Aeromonas spp., Pasteurella spp., Brucella spp., Helicobacter spp., Campylobacter spp., Tullair Francisella spp., Legionella spp., Vibrio spp., Neisseria spp., Mycobacterium spp., Yersinia pestis, Rickettsia spp.

[0043] Gram-positive: Staphylococcus, Enterococcus, Streptococcus, Bacillus anthracis.

[0044] For example, Gram-negative bacteria can include: Enterobacteriaceae, such as *Escherichia coli*; *Enterobacter* spp. (e.g., *Enterobacter aerogenes*, *Enterobacter clumps*, and *Enterobacter cloacae*); *Citrobacter* spp. (e.g., *Citrobacter freundii* and *Citrobacter diagenesis*); *Pseudomonas* spp. (e.g., *Pseudomonas aeruginosa*, *Stenotrophomonas maltophilia*, *Alcaligenes*, *Pseudomonas aeruginosa*, *Pseudomonas fluorescens*, *Pseudomonas mendoza*, *Pseudomonas montelukastii*, *Pseudomonas perforatum*, *Alcaligenes*, *Pseudomonas putida*, and *Pseudomonas stearothermii*); *Yersinia* spp. (e.g., *Yersinia enterocolitica*, *Yersinia plague*, and *Yersinia pseudotuberculosis*); *Helicobacter* spp. (e.g., *Helicobacter pylori*, *Helicobacter homosexualus*). *Helicobacter pylori*; *Acinetobacter* spp. (e.g., *Acinetobacter baumannii*, *Acinetobacter calcium acetate*, *Acinetobacter hemolyticus*, *Acinetobacter johnsonii*, *Acinetobacter jumbo*, *Acinetobacter loffibraria*, and *Acinetobacter radiata*); *Morganella* spp. (e.g., *Morganella morganii*); *Salmonella* spp. (*Salmonella enterica* and *Salmonella typhi*); *Shigella* spp. (e.g., *Shigella dysenteriae*, *Shigella flexneri*, *Shigella baumannii*, and *Shigella sonnei*); *Klebsiella* spp. (e.g., *Klebsiella pneumoniae*, *Klebsiella acidogenic*, *Klebsiella ornithine-lysinic*, *Klebsiella phytophyte*, *Klebsiella odorinae*, *Klebsiella terrestrial*, *Klebsiella granulomatosa* (*Klebsiella granulomatosa*), and *Klebsiella rhinosclerotium*); *Burkholderia oligotrophomorpha*; *Francis tulariiflora*. Serratia spp. (e.g., Serratia decoloris and Serratia liquefaction); Proteus spp. (e.g., Proteus mirabilis, Proteus remdesivir, and Proteus vulgaris); Providencia spp. (e.g., Providencia alkaligenes, Providencia remdesivir, and Providencia squarrosi); Haemophilus spp. (e.g., Haemophilus influenzae, Haemophilus dulcis, Haemophilus aegyptiacus, Haemophilus parainfluenzae, Haemophilus hemolyticus, and Haemophilus parahemolyticus); Aeromonas spp. (e.g., Aeromonas hydrophila, Aeromonas guinea pig, and Aeromonas vesiculosus); Pasteurella spp. (e.g., Pasteurella aerogenes, Pasteurella belladonna, Pasteurella canis, Pasteurella biteis, Pasteurella foetida, Pasteurella hemolyticus, Pasteurella multocida subsp. multocida, Pasteurella multocida). * *Pasteurella multocida* subspecies, *Pasteurella septicemia* subspecies, *Pasteurella pneumophila*, and *Pasteurella laryngii*; *Brucella* spp. (e.g., *Brucella abortus*, *Brucella canis*, *Brucella malata*, and *Brucella suis*); *Campylobacter* spp. (e.g., *Campylobacter jejuni*, *Campylobacter coli*, *Campylobacter guinea*, and *Campylobacter fetus*); *Legionella* spp. (e.g., *Legionella* var. *parionella*, *Legionella Birmingham*, *Legionella bozmanni*, *Legionella Cincinnati*, *Legionella dumović*, *Legionella freundii*, *Legionella golemani*, *Legionella haematobium*, *Legionella Israelites*, *Legionella Jordaniana*, *Legionella Lansing*, *Legionella Long Beach*, *Legionella McKaylen*, *Legionella McDard*, *Legionella Oak Ridge*, *Legionella pneumophila*, *Legionella Helen*, *Legionella Tucson*, and *Legionella Ward*).Vibrio species (e.g., Vibrio cholerae and Vibrio parahaemolyticus, Vibrio alginate, Vibrio sharkii, Vibrio fluvibrio, Vibrio freundii, Vibrio cholerae, Vibrio medroxyprolifera, Vibrio mimicus, and Vibrio vulnificus); Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria greya, Neisseria longa, Neisseria flavum, Neisseria lactosa, Neisseria myxobolus, Neisseria drya, Neisseria flavescens, and Neisseria wiltii. Mycobacterium genus (e.g., Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium sporadicum, Mycobacterium marinum, Mycobacterium kansasense, Mycobacterium turkeyense, Mycobacterium abscessum, Mycobacterium leprae, Mycobacterium smegmatis, Mycobacterium africanum, Mycobacterium brevicornum, Mycobacterium asiaticum, Mycobacterium aureum, Mycobacterium bovis, Mycobacterium deltae, Mycobacterium winterii, Mycobacterium cuneiformis, Mycobacterium chub, Mycobacterium koblenzii, Mycobacterium quercetum, Mycobacterium kusnezoffii, Mycobacterium cirrhosa, Mycobacterium caudans, Mycobacterium gastritis, Mycobacterium Genevai, Mycobacterium Gordonii, Mycobacterium guidei, Mycobacterium haemophilus, Mycobacterium hemoglobinii, Mycobacterium niger, Mycobacterium medulans, Mycobacterium heidelbergii, Mycobacterium stoloniferum, Mycobacterium marmosum, Mycobacterium stoloniferum) Microgenicum, Mycobacterium villiformis, Mycobacterium myxogenum, Mycobacterium neogoldenum, Mycobacterium achromatum, Mycobacterium exogenum, Mycobacterium spp., Mycobacterium scrofula, Mycobacterium hypoglaucum, Mycobacterium simianum, Mycobacterium spp., Mycobacterium spp., Mycobacterium spp., Mycobacterium thermoscientificum, Mycobacterium tripletus, minor mycobacteria, Mycobacterium toscanatum, Mycobacterium ulcerans, Mycobacterium bovis, Mycobacterium wartii, and Mycobacterium bufo; Rickettsia (e.g., Rickettsia or Coxella burgdorferi).

[0045] For example, Gram-positive bacteria can be Staphylococcus (e.g., Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus auriculata, Staphylococcus capitis subsp. capitis, Staphylococcus capitis subsp. capitis, Staphylococcus coli subsp. coli, Staphylococcus coli subsp. capitis, Staphylococcus coli subsp. capitis, Staphylococcus coli subsp. capitis, Staphylococcus equi, Staphylococcus aureus, Staphylococcus hemolyticus, Staphylococcus hominis subsp. hominis, Staphylococcus hominis neomycin-resistant septicemia subsp. hominis, Staphylococcus suis, Staphylococcus intermedius, Staphylococcus ludensburgii, Pasteurella multocida). Staphylococci, Staphylococcus glycolyticus, Staphylococcus stearothermiae subsp. stearothermiae, Staphylococcus stearothermiae coagulans subsp. stearothermiae, Staphylococcus aureus, Staphylococcus pseudosporidis, Staphylococcus wartii, and Staphylococcus xyloseus; Streptococci (e.g., β-hemolytic pyogenic streptococci such as Streptococcus agalactiae, Streptococcus canis, Streptococcus dysgalactiae subsp. dysgalactiae, Streptococcus equine subsp. equine, Streptococcus equine subsp. equine, Streptococcus dolphinus, Streptococcus suis and Streptococcus pyogenes, Streptococcus microoxygenans ("Miller" Streptococcus)). Examples include *Streptococcus pharyngans*, *Streptococcus constellus* subspecies, *Streptococcus constellus* pharyngitis subspecies, and *Streptococcus intermedia*; "mild" oral streptococci (α-hemolytic); "green" streptococci, such as *Streptococcus mildus*, *Streptococcus stomatus*, *Streptococcus sanguinis*, *Streptococcus sterni*, *Streptococcus glomerulosa*, and *Streptococcus parahalus*; "salivary" streptococci (non-hemolytic), such as *Streptococcus stomatus* and *Streptococcus vestibulus*; and "variant" streptococci (dental surface streptococci), such as *Streptococcus cristatus*, *variant*, *Streptococcus mutans*, and *Streptococcus distantis*. Streptococci include: *Streptococcus microcarpa*, *Streptococcus bovis*, *Streptococcus faecalis*, *Streptococcus equi*, *Streptococcus pneumoniae*, and *Streptococcus suis*, or streptococci that can be classified into groups A, B, C, D, E, G, L, P, U, or V; enterococci (e.g., *Enterococcus avium*, *Enterococcus flavomarginata*, *Enterococcus cecum*, *Enterococcus differentialis*, *Enterococcus durableis*, *Enterococcus faecalis*, *Enterococcus faecium*, *Enterococcus faecalis*, *Enterococcus flavomarginata*, *Enterococcus montelukast*, *Enterococcus pseudoavium*, *Enterococcus hydatus*, and *Enterococcus monnieri*); and Bacillus anthracis.

[0046] The bacterial infections treated with the combination therapy described herein can be Gram-negative or Gram-positive bacterial infections. Specific Gram-negative bacteria that can be treated with the combination therapy of this invention include:

[0047] Enterobacteriaceae, such as *Escherichia coli*, *Klebsiella* spp. (e.g., *Klebsiella pneumoniae* and *Klebsiella acidogenic*), and *Proteus* spp. (e.g., *Proteus mirabilis*, *Proteus remdesivir*, and *Proteus vulgaris*); *Haemophilus influenzae*; *Mycobacterium* spp., such as *Mycobacterium tuberculosis*; and *Enterobacter* spp. (e.g., *Enterobacter cloacae*). Preferably, the bacteria are Enterobacteriaceae, such as *Escherichia coli* and *Klebsiella* spp. (e.g., *Klebsiella pneumoniae* and *Klebsiella acidogenic*). Particularly preferred are *Escherichia coli* and *Klebsiella pneumoniae* (e.g., *Klebsiella pneumoniae* subsp. *pneumoniae*).

[0048] The combinations of this invention are particularly beneficial in treating (multiple)-drug-resistant ((M)DR) bacteria. In the case of Enterobacteriaceae, drug resistance most commonly accumulates to carbapenemases, i.e., carbapenemase-resistant strains and "extended-spectrum β-lactamase" (ESBL) strains, such as New Delhi metallo-β-lactamase-1 (NDM-1) resistant Klebsiella pneumoniae and NDM-1 type Escherichia coli. The combinations of this invention are also particularly effective against carbapenemase-producing Enterobacteriaceae (CPE). Other drug-resistant strains, such as colistin-resistant strains, and carbapenemase-resistant strains of bacteria other than Enterobacteriaceae, including carbapenem-resistant Acinetobacter and carbapenem-resistant Pseudomonas, carrying the blaKPC gene. The combinations of this invention are particularly effective against Pseudomonas aeruginosa and Acinetobacter baumannii.

[0049] In various embodiments, the combination of the present invention has a beneficial effect against ESKAPE pathogens. These are six highly toxic and typical antibiotic-resistant bacterial pathogens, including Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. This group of Gram-positive and Gram-negative bacteria can evade or “escape” commonly used antibiotics due to their increasingly enhanced multidrug resistance. Therefore, the combination of the present invention has a beneficial effect against (M)DR strains of ESKAPE pathogens.

[0050] Advantageously, in various embodiments, the combinations of the present invention can have a broader spectrum of activity than a single therapy or a combination of only two active substances. In particular, the various combinations can be effective against at least Acinetobacter, Pseudomonas, and Enterobacteriaceae, bacteria identified by the World Health Organization as including multidrug-resistant bacteria, for which new antibiotics are urgently needed. The combinations are also effective against Staphylococcus aureus, including methicillin-sensitive and methicillin-resistant Staphylococcus aureus.

[0051] It should be noted that while combinations as claimed in this application may initially prove functional in treating (M)DR strains, they can subsequently be used to treat non-resistant strains. This is particularly valuable in the case of currently claimed combinations, where primary treatments for Enterobacteriaceae such as *Escherichia coli* and *Klebsiella* spp. (e.g., *Klebsiella pneumoniae* and *Klebsiella acidogenic*), *Acinetobacter* spp., and / or *Pseudomonas* spp. are antimicrobial drugs, which are expensive due to existing patent protection. In the current climate where governments seek to reduce healthcare costs, replacing such "ethical" drugs with combinations of "common" antibiotics is considered beneficial both from a therapeutic and financial / economic perspective.

[0052] The combinations of the present invention can be used to treat infections associated with any of the aforementioned bacterial organisms, and in particular, they can be used to kill proliferating and / or clinically latent microorganisms associated with such infections (e.g., ESKAPE pathogen bacterial infections).

[0053] In various embodiments, the combination of the present invention is effective in treating infections caused by: (1) carbapenem-resistant *Escherichia coli*, *Klebsiella* spp., *Acinetobacter* spp., *Pseudomonas aeruginosa*, *Serratia* spp., or *Proteus* spp.; (2) MRSA, vancomycin-resistant *Staphylococcus aureus* (VRSA), vancomycin-resistant *Enterococcus faecalis* (VRE), clarithromycin-resistant *Helicobacter pylori*, or quinolone-resistant *Salmonella*; or (3) penicillin-resistant *Streptococcus pneumoniae*, ampicillin-resistant *Haemophilus influenzae*, or quinolone-resistant *Shigella* spp. In various embodiments, the combination of the present invention is effective in treating infections caused by *Pseudomonas aeruginosa*, *Acinetobacter baumannii*, and MRSA.

[0054] Specific conditions for which the combination therapy of the present invention can be used include tuberculosis (such as pulmonary tuberculosis, non-pulmonary tuberculosis (such as tuberculous lymphadenitis, genitourinary tuberculosis, bone and joint tuberculosis, tuberculous meningitis) and miliary tuberculosis), anthrax, abscess, acne vulgaris, actinomycosis, asthma, bacterial dysentery, bacterial conjunctivitis, bacterial keratitis, bacterial vaginosis, botulism, brucellosis, bone and joint infections, bronchitis (acute or chronic), brucellosis, burns, cat scratch disease, cellulitis, chancroid, cholangitis, cholecystitis, cutaneous diphtheria, cystic fibrosis, cystitis, diffuse panbronchiolitis, diphtheria, dental caries, upper respiratory tract diseases, eczema, empyema, endocarditis, and endometritis. Inflammation, enteritis, enteritis, epididymitis, epiglottitis, erysipelis, erysipelas, erysipelas-like rash, erythema, eye infections, furuncles, Gardnerella vaginalis infection, gastrointestinal infections (gastroenteritis), genital infections, gingivitis, gonorrhea, granuloma inguinale, Havershill fever, infectious burns, post-dental surgical infections, oral region infections, prosthesis-related infections, intra-abdominal abscess, Legionnaires' disease, leprosy, leptospirosis, listeriosis, liver abscess, Lyme disease, lymphogranuloma venereum, mastitis, mastoiditis, meningitis and nervous system infections, foot mycomas, nocardiac infection (e.g., Madura's foot), nonspecific urethritis, conjunctivitis (e.g., neonatal ophthalmia). Osteomyelitis, otitis (e.g., otitis externa and otitis media), orchitis, pancreatitis, paronychia, pyelonephritis, peritonitis, appendicitis peritonitis, pharyngitis, cellulitis, pinta disease, plague, pleural effusion, pneumonia, postoperative wound infection, postoperative gas gangrene, prostatitis, pseudomembranous colitis, psittacosis, emphysema, pyelonephritis, pyoderma (e.g., impetigo), Q fever, rat-bite fever, reticulosis, ricin poisoning, Ritter disease, salmonellosis, salpingitis, septic arthritis, septic infection, sepsis, sinusitis, skin infections (e.g., cutaneous granuloma, impetigo, folliculitis, and furuncles), syphilis, systemic infections, tonsillitis, toxic shock syndrome, trachoma. Tularemia, typhus, typhus (e.g., epidemic typhus, murine typhus, scrub typhus, and spotted fever), urethritis, wound infection, yaws, aspergillosis, candidiasis (e.g., oropharyngeal candidiasis, vaginal candidiasis, or balanitis), cryptococcosis, jaundice, histoplasmosis, chafing, mucormycosis, tinea (e.g., tinea corporis, tinea capitis, tinea cruris, tinea pedis, and onychomycosis), onychomycosis, tinea versicolor, tinea, and sporotrichosis; or infections caused by MSSA, MRSA, Staphylococcus epidermidis, Streptococcus agalactiae, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Klebsiella pneumoniae, Proteus mirabilis, Proteus repens, Proteus vulgaris, Haemophilus influenzae, Enterococcus faecalis, and Enterococcus faecium.

[0055] Specific conditions that can be treated with the combination therapy of this invention also include diseases caused by Gram-negative bacteria, such as abscesses, asthma, bacterial dysentery, bacterial conjunctivitis, bacterial keratitis, bacterial vaginosis, bone and joint infections, bronchitis (acute or chronic), brucellosis, burns, cat scratch disease, cellulitis, chancroid, cholangitis, cholecystitis, cystic fibrosis, cystitis, nephritis, diffuse panbronchiolitis, dental caries, upper respiratory tract diseases, empyema, endocarditis, endometritis, enteritis, epididymitis, epiglottitis, eye infections, furuncles, Gardnerella vaginalis vaginitis, gastrointestinal infections (gastroenteritis), genital infections, gingivitis, gonorrhea, granuloma inguinale, Havershill fever, infectious burns, post-dental surgical infections, oral region infections, prosthesis-related infections, intra-abdominal abscesses, Legionnaires' disease, leptospirosis, listeriosis, liver abscesses, Lyme disease, and sexually transmitted diseases. Lymphogranuloma venereum, mastitis, mastoiditis, meningitis and nervous system infections, nonspecific urethritis, ophthalmitis (e.g., neonatal ophthalmitis), osteomyelitis, otitis (e.g., otitis externa and otitis media), orchitis, pancreatitis, paronychia, pyelonephritis, peritonitis, appendicitis peritonitis, pharyngitis, pleural effusion, pneumonia, postoperative wound infection, postoperative gas gangrene, prostatitis, pseudomembranous colitis, psittacosis, pyelonephritis, Q fever, Ritter Infections caused by Escherichia coli, Salmonella, salpingitis, septic arthritis, septic infection, sepsis, systemic infection, tonsillitis, trachoma, typhoid fever, urethritis, urinary tract infection, wound infection; or infections caused by Escherichia coli, Klebsiella pneumoniae, Klebsiella pneumoniae, Proteus mirabilis, Proteus remdesivir, Proteus vulgaris, Haemophilus influenzae, Enterococcus faecalis, Enterococcus faecium, Enterobacter cloacae, Acinetobacter baumannii, and Pseudomonas aeruginosa.

[0056] Preferably, the combination of the present invention is used to treat acute or complicated urinary tract infections, acute or complicated skin and soft tissue infections, intra-abdominal infections, upper respiratory tract infections, community-acquired pneumonia, hospital-acquired pneumonia, ventilator-associated pneumonia, or bloodstream infections.

[0057] It should be understood that the term "treatment" as used in this article extends to prevention as well as the treatment of identified diseases or symptoms.

[0058] As used herein, the term “pharmaceuticalally acceptable derivative” means: (a) a pharmaceutically acceptable salt; (b) a solvate (including hydrates) and / or (c) a prodrug (if applicable).

[0059] Pharmaceutically acceptable salts of compounds included in the combinations of the present invention include their suitable acid addition salts or base salts. A review of suitable pharmaceutical salts can be found in Berge et al., J Pharm Sci, 66, 1-19 (1977).

[0060] Suitable acid addition salts include carboxylates (e.g., formate, acetate, trifluoroacetate, propionate, isobutyrate, heptanoate, decanoate, decanoate ester, octanoate, stearate, acrylate, hexanoate, propionate, ascorbate, citrate, glucuronide, glutamate, glycolate, α-hydroxybutyrate, lactate, tartrate, phenylacetate, mandelate, phenylpropionate, phenylbutyrate, benzoate, chlorobenzoate, methylbenzoate, hydroxybenzoate, methoxybenzoate, dinitrobenzoate, o-acetoxybenzoate, salicylate, nicotinate, isonicotinate, cinnamate, oxalate, malonyl benzoate, etc.). Salts include acetic acid salts, succinates, octanoates, sebacic acid salts, fumarates, malates, maleates, hydroxymaleates, hippurates, phthalates, or terephthalates; halide salts (e.g., chloride, bromide, or iodide salts); sulfonates (e.g., benzenesulfonates, methyl-, brominated, or chloro-benzenesulfonates, xylenesulfonates, methanesulfonates, ethanesulfonates, propanesulfonates, hydroxyethanesulfonates, 1- or 2-naphthalenesulfonates, or 1,5-naphthalenesulfonates); or sulfates, pyrosulfites, bisulfites, sulfites, bisulfites, phosphates, monohydrogen phosphates, dihydrogen phosphates, metaphosphates, pyrophosphates, or nitrates. Suitable alkali salts include metal salts such as sodium, calcium, and amine salts.

[0061] For example, colistin sulfate, polymyxin B sulfate, doxycycline hydrochloride (doxycycline hydrochloride hemiethanolate hemihydrate), doxycycline hydrochloride, doxycycline monohydrate, fosfomycin tromethamine, fosfomycin calcium, fosfomycin sodium, fosfomycin disodium, levofloxacin hemihydrate, and meropenem trihydrate are commercially available from Sigma Aldrich. Other suppliers are also known in the art.

[0062] As used herein, the term "prodrug" refers to an antimicrobial compound in which one or more groups have been modified such that the modification is reversible upon administration to a human or mammalian subject. This reversal is typically carried out by an enzyme naturally present in the subject, but it is possible to administer a second drug along with such a prodrug to achieve reversal in vivo. Examples of such modifications include ester formation (e.g., any of the above), where reversal can be carried out by esterases, etc. Other such systems are well known to those skilled in the art.

[0063] For example, zidovudine is a prodrug that must be phosphorylated to its active 5'-triphosphate metabolite.

[0064] Polymyxin E (or colistin) is commercially available as the following mesylate derivatives: colistin sodium methanesulfonate or colistin sodium methanesulfonate (CMS). Colistin sodium methanesulfonate is a prodrug. It is produced by the reaction of colistin with formaldehyde and sodium bisulfite, which results in the addition of a sulfomethyl group to the primary amine of colistin. In aqueous solution, it undergoes hydrolysis to form a complex mixture of partially sulfonated derivatives and colistin.

[0065] This invention includes the use of these pharmaceutically acceptable derivatives and prodrugs. In particular, this invention includes the use of colistin and its pharmaceutically acceptable derivatives, including colistin sulfate, colistin sodium methanesulfonate, and colistin sodium methanesulfonate. The term "colistin" may be used interchangeably with these pharmaceutically acceptable derivatives known in the art.

[0066] Where appropriate, the invention also includes all enantiomers and tautomers of the said compound. Those skilled in the art are familiar with compounds possessing optical properties (one or more chiral carbon atoms) or tautomer characteristics. The corresponding enantiomers and / or tautomers can be isolated or prepared by methods known in the art.

[0067] Some compounds included in the combinations of this invention can exist as stereoisomers and / or geometric isomers; for example, they can have one or more asymmetric and / or geometric centers, and thus can exist in two or more stereoisomers and / or geometric forms. This invention contemplates all individual stereoisomers and geometric isomers and mixtures thereof using these inhibitors. Terms used in the claims include these forms provided that said forms retain adequate functional activity (although not necessarily to the same degree).

[0068] This invention also includes all suitable isotopic variants of the said compound or a pharmaceutically acceptable salt thereof. An isotopic variant or a pharmaceutically acceptable salt thereof is defined as having at least one atom replaced by an atom having the same number of atoms but a different atomic weight than those commonly found in nature. Examples of isotopes that can be incorporated include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, and chlorine, such as 2H, 3H, 13C, 14C, 15N, 17O, 18O, 31P, 32P, 35S, 18F, and 36Cl, respectively. Certain isotopic variants, such as those incorporating radioactive isotopes (e.g., 3H or 14C), can be used for drug and / or matrix tissue distribution studies. Tritium (i.e., 3H) and carbon-14 (i.e., 14C) isotopes are particularly preferred due to their ease of preparation and detection. Furthermore, substitution with isotopes such as deuterium (i.e., 2H) can offer certain therapeutic advantages due to its higher metabolic stability, such as increased in vivo half-life or reduced dose requirement, and may therefore be preferred in some cases. Isotope variants can generally be prepared using suitable isotope variants with appropriate reagents through routine procedures.

[0069] The compounds used in the combinations of this invention, including their pharmaceutically acceptable derivatives or prodrugs, are commercially available and / or can be prepared by synthetic methods known in the art. Zidovudine, polymyxin E, polymyxin B, doxycycline, fosfomycin, levofloxacin, meropenem, colistin sulfate, colistin methanesulfonate sodium, colistin methanesulfonate sodium, polymyxin B sulfate, doxycycline hydrochloride (doxycycline hydrochloride hemiethanolate hemihydrate), doxycycline hydrochloride, doxycycline monohydrate, fosfomycin tromethamine, fosfomycin calcium, fosfomycin sodium, fosfomycin disodium, levofloxacin hemihydrate, and meropenem trihydrate are available, for example, from Sigma-Aldrich®. Other commercial suppliers are known in the art.

[0070] Zidovudine is 1-[(2R, 4S, 5S)-4-azido-5-(hydroxymethyl)oxacyclopentadien-2-yl]-5-methylpyrimidine-2,4-dione, marketed under the name Retrovir®, and is available by prescription. It is also known as 3'-azido-3'-deoxythymidine or "AZT," and its chemical structure is as follows:

[0071] Ceftazidime is sold under brand names such as Fortaz and is a third-generation cephalosporin antibiotic used to treat a variety of bacterial infections. It has the following chemical structure:

[0072] Polymyxin E, also known as colistin, is an antibiotic used as a last resort to treat multidrug-resistant Gram-negative infections, including pneumonia. These infections can involve bacteria such as Pseudomonas aeruginosa, Klebsiella pneumoniae, or Acinetobacter. It is available in two forms: colistin mesylate, which can be injected intravenously, intramuscularly, or by inhalation, and colistin sulfate, which is primarily applied topically or orally. It has the following chemical structure:

[0073] Polymyxin B, marketed under brand names such as Poly-Rx, is an antibiotic used to treat meningitis, pneumonia, sepsis, and urinary tract infections. It can be administered intravenously, intramuscularly, via cerebrospinal fluid injection, or by inhalation. It has the following chemical structure:

[0074] Doxycycline is a broad-spectrum tetracycline antibiotic used to treat infections caused by bacteria and certain parasites. It is used to treat bacterial pneumonia, acne, chlamydia, Lyme disease, cholera, typhus, and syphilis. Doxycycline can be administered orally or intravenously. It has the following chemical structure:

[0075] Fosfomycin, marketed under brand names such as Monurol, is an antibiotic primarily used to treat lower urinary tract infections (UTIs). It is usually administered orally and has the following chemical structure:

[0076] Levofloxacin, marketed under brand names such as Levaquin, is an antibiotic used to treat a variety of bacterial infections, including acute bacterial sinusitis, pneumonia, urinary tract infections, chronic prostatitis, and some types of gastroenteritis. It can be administered orally, intravenously, or as eye drops. It is the (S)-isomer of ofloxacin and has the following chemical structure:

[0077] Meropenem, marketed under brand names such as Merrem, is an intravenously administered β-lactam antibiotic used to treat various bacterial infections. Some of these infections include meningitis, intra-abdominal infections, pneumonia, sepsis, and anthrax. It belongs to the carbapenem family and has the following chemical structure:

[0078] The synergistic combination of the present invention comprises three antimicrobial agents. These agents are grouped in the appended claims to cover the exemplary combination in the most effective manner.

[0079] The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof. The second antimicrobial agent is selected from zidovudine, doxycycline, and pharmaceutically acceptable derivatives thereof; and the third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof; provided that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof. The abandoned combination is the subject matter of the co-pending GB 2213753.3.

[0080] In some embodiments, the second antimicrobial agent is preferably zidovudine or a pharmaceutically acceptable derivative thereof. More preferably, meropenem and zidovudine or a pharmaceutically acceptable derivative thereof are combined with a third antimicrobial agent, said third antimicrobial agent being fosfomycin, levofloxacin, polymyxin E, polymyxin B, or a pharmaceutically acceptable derivative thereof. For example, the combination could be:

[0081] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and fosfomycin or a pharmaceutically acceptable derivative thereof;

[0082] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and levofloxacin or a pharmaceutically acceptable derivative thereof;

[0083] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and polymyxin E or a pharmaceutically acceptable derivative thereof; or

[0084] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and polymyxin B or a pharmaceutically acceptable derivative thereof.

[0085] More preferably, meropenem and zidovudine or their pharmaceutically acceptable derivatives are combined with a third antimicrobial agent, said third antimicrobial agent being fosfomycin, polymyxin E, polymyxin B, or their pharmaceutically acceptable derivatives. For example, the combination could be:

[0086] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and fosfomycin or a pharmaceutically acceptable derivative thereof;

[0087] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and polymyxin E or a pharmaceutically acceptable derivative thereof; or

[0088] Meropenem or a pharmaceutically acceptable derivative thereof; zidovudine or a pharmaceutically acceptable derivative thereof; and polymyxin B or a pharmaceutically acceptable derivative thereof.

[0089] In other embodiments, the second antimicrobial agent is preferably doxycycline or a pharmaceutically acceptable derivative thereof. More preferably, meropenem and doxycycline or a pharmaceutically acceptable derivative thereof are combined with a third antimicrobial agent, said third antimicrobial agent being fosfomycin, levofloxacin, polymyxin E, polymyxin B, or a pharmaceutically acceptable derivative thereof. For example, the combination could be:

[0090] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and fosfomycin or a pharmaceutically acceptable derivative thereof;

[0091] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and levofloxacin or a pharmaceutically acceptable derivative thereof;

[0092] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and polymyxin E or a pharmaceutically acceptable derivative thereof; or

[0093] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and polymyxin B or a pharmaceutically acceptable derivative thereof.

[0094] In other embodiments, the second antimicrobial agent is preferably doxycycline or a pharmaceutically acceptable derivative thereof. More preferably, meropenem and doxycycline or a pharmaceutically acceptable derivative thereof are combined with a third antimicrobial agent, said third antimicrobial agent being fosfomycin, levofloxacin, or a pharmaceutically acceptable derivative thereof. For example, the combination could be:

[0095] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and fosfomycin or a pharmaceutically acceptable derivative thereof; or

[0096] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; and levofloxacin or a pharmaceutically acceptable derivative thereof.

[0097] In a further embodiment, the combination of the present invention may also include a fourth antimicrobial agent. In such an embodiment, the second antimicrobial agent is preferably doxycycline or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is preferably fosfomycin or a pharmaceutically acceptable derivative thereof. In various embodiments, the fourth antimicrobial agent may be ceftazidime, polymyxin E, or a pharmaceutically acceptable derivative thereof. For example, the combination may be:

[0098] Meropenem or a pharmaceutically acceptable derivative thereof; doxycycline or a pharmaceutically acceptable derivative thereof; fosfomycin or a pharmaceutically acceptable derivative thereof; and ceftazidime or a pharmaceutically acceptable derivative thereof.

[0099] Meropenem or a pharmaceutically acceptable derivative thereof, doxycycline or a pharmaceutically acceptable derivative thereof, fosfomycin or a pharmaceutically acceptable derivative thereof, and polymyxin E or a pharmaceutically acceptable derivative thereof.

[0100] The combinations of the present invention can be grouped using one or more common antimicrobial agents. In one embodiment, the combination includes meropenem or a pharmaceutically acceptable derivative thereof as a first antimicrobial agent and zidovudine or a pharmaceutically acceptable derivative thereof as a second antimicrobial agent.

[0101] In another embodiment, the combination comprises meropenem or a pharmaceutically acceptable derivative thereof as a first antimicrobial agent and doxycycline or a pharmaceutically acceptable derivative thereof as a second antimicrobial agent.

[0102] In another embodiment, the combination includes meropenem or a pharmaceutically acceptable derivative thereof as a first antimicrobial agent, doxycycline or a pharmaceutically acceptable derivative thereof as a second antimicrobial agent, and fosfomycin or a pharmaceutically acceptable derivative thereof as a third antimicrobial agent.

[0103] The compounds according to the invention can be administered as raw materials, but are preferably provided in the form of pharmaceutical compositions. The compounds can be used either as individual formulations or as single combination formulations. When combined in the same formulation, it should be understood that both compounds must be stable and compatible with each other and with other components of the formulation.

[0104] The formulations of the present invention include those suitable for oral administration, parenteral administration (including subcutaneous administration, such as by injection or by depot tablets, intrathecal administration, intramuscular administration, such as by sustained-release and intravenous administration), and rectal administration, or those suitable for inhalation or blow-through administration. The most suitable route of administration may depend on the patient's condition and symptoms. Preferably, the compositions of the present invention are formulated for oral administration.

[0105] The formulation can be readily available in unit dose form and can be prepared by any method known in the pharmaceutical field, such as the method described in "Remington: The Science and Practice of Pharmacy", Lippincott Williams and Wilkins, 21st edition, (2005). Suitable methods include the step of combining the active ingredient with a carrier constituting one or more excipients. Generally, the preparation of a formulation involves uniformly and tightly combining the active ingredient with a liquid carrier or a subdivided solid carrier, or both, and then, if desired, shaping the product into the desired formulation. It should be understood that when the two active ingredients are administered independently, each can be administered in a different manner.

[0106] When formulated with excipients, the active ingredient may be present at a concentration of 0.1 to 99.5% (e.g., from 0.5 to 95%) of the total mixture by weight; conveniently, from 30 to 95% for tablets and capsules, and from 0.01 to 50% (e.g., from 3 to 50%) for liquid formulations.

[0107] The concentration of each antimicrobial agent in the synergistic combination is equal to or less than the minimum inhibitory concentration (MIC) of a single therapy targeting the bacteria described in the combination. 单 Therefore, unless otherwise stated, "MIC" as used in this article should be understood as MIC. 单 Preferably, the concentration of at least one antimicrobial agent in the synergistic combination is below the MIC. 单 More preferably, the concentrations of at least two antimicrobial agents in the synergistic combination are below the MIC. 单 Using such a concentration is advantageous because it avoids toxicity issues and reduces the likelihood of developing antimicrobial resistance to one or more drugs in the combination.

[0108] In various implementation schemes, the concentration of meropenem is 1x MIC or lower for the bacteria targeted by the combination used, where MIC is the lowest inhibitory concentration of meropenem used alone against said bacteria. 单 Preferably, the concentration of meropenem can be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of meropenem is 0.25 × MIC for the bacteria targeted by the combination used. 单 Or even lower. Most preferably, the concentration of meropenem is 0.125 × MIC for the bacteria targeted by the combination used. 单 Or even lower. In some implementations, the concentration of meropenem is as low as 0.03125 × MIC for the bacteria targeted by the combination used.单 This is equivalent to 1 / 32 MIC 单 .

[0109] For example, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the concentration of meropenem can be about 128 mg / L or lower. In a preferred embodiment, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the concentration of meropenem can be about 0.125 to about 128 mg / L. In another preferred embodiment, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the concentration of meropenem can be about 0.25 to about 128 mg / L. More preferably, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the concentration of meropenem can be about 4 to about 32 mg / L.

[0110] As another example, in combinations demonstrating a synergistic effect against Acinetobacter baumannii, the concentration of meropenem can be about 256 mg / L or less. In a preferred embodiment, in combinations demonstrating a synergistic effect against Acinetobacter baumannii, the concentration of meropenem can be about 0.00781 to about 256 mg / L. In another preferred embodiment, in combinations demonstrating a synergistic effect against Acinetobacter baumannii, the concentration of meropenem can be about 1 to about 256 mg / L. More preferably, in combinations demonstrating a synergistic effect against Acinetobacter baumannii, the concentration of meropenem can be about 2 to about 128 mg / L. Most preferably, in combinations demonstrating a synergistic effect against Acinetobacter baumannii, the concentration of meropenem can be about 2 to about 32 mg / L.

[0111] As another example, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the concentration of meropenem can be about 4 mg / L or lower. In a preferred embodiment, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the concentration of meropenem can be about 0.5 to about 4 mg / L. More preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the concentration of meropenem can be about 1 to about 4 mg / L.

[0112] As another example, in combinations demonstrating a synergistic effect against MSSA, the concentration of meropenem can be about 0.25 mg / L or lower. In a preferred embodiment, in combinations demonstrating a synergistic effect against MSSA, the concentration of meropenem can be about 0.0313 to about 0.25 mg / L.

[0113] As another example, in combinations demonstrating a synergistic effect against MRSA, the concentration of meropenem can be about 32 mg / L or lower. In a preferred embodiment, in combinations demonstrating a synergistic effect against MRSA, the concentration of meropenem can be about 1 to about 32 mg / L. More preferably, in combinations demonstrating a synergistic effect against MRSA, the concentration of meropenem can be about 4 to about 32 mg / L.

[0114] In various implementation schemes, the concentration of zidovudine is 1xMIC for the bacteria targeted by the combination used. 单 Or lower. Preferably, the concentration of zidovudine may be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of zidovudine is 0.25 × MIC for the bacteria targeted by the combination used. 单 Or even lower. Most preferably, the concentration of zidovudine is 0.125 × MIC for the bacteria targeted by the combination used. 单 Or lower.

[0115] As an example, in combinations that demonstrate synergistic effects against Pseudomonas aeruginosa, the concentration of zidovudine may be about 512 mg / L or lower, preferably about 0.03125 to about 512 mg / L, more preferably about 0.5 to about 128 mg / L.

[0116] In another example, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, the concentration of zidovudine may be about 512 mg / L or less, preferably about 0.03125 to about 512 mg / L, and even more preferably about 0.25 to about 128 mg / L.

[0117] In another example, in combinations that demonstrate synergistic effects against Klebsiella pneumoniae, the concentration of zidovudine may be about 1000 mg / L or lower, preferably about 7.8 to about 1000 mg / L, and even more preferably about 62.5 to about 1000 mg / L.

[0118] In another instance, in combinations that demonstrate a synergistic effect against MSSA, the concentration of zidovudine may be about 1000 mg / L or lower, preferably about 15.63 to about 1000 mg / L.

[0119] As those skilled in the art will understand, the concentration range of zidovudine as a second antimicrobial agent can be combined with the concentration range of meropenem as a first antimicrobial agent, and further combined with the following concentration ranges of each of fosfomycin, levofloxacin, polymyxin E, and polymyxin B as third antimicrobial agents as defined below. Those skilled in the art will also understand that all concentration ranges herein apply to pharmaceutically acceptable derivatives of the compounds.

[0120] In various embodiments, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, meropenem is used at a concentration of about 0.125 to about 128 mg / L, and zidovudine is used at a concentration of about 0.03125 to about 512 mg / L. In various embodiments, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, meropenem is used at a concentration of about 0.25 to about 128 mg / L, and zidovudine is used at a concentration of about 0.03125 to about 512 mg / L. Preferably, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the meropenem concentration may be about 4 to about 32 mg / L, and the zidovudine concentration may be about 0.03125 to about 512 mg / L. Most preferably, in combinations exhibiting synergistic effects against *Pseudomonas aeruginosa*, the meropenem concentration may be about 4 to about 32 mg / L, and the zidovudine concentration may be about 0.5 to about 128 mg / L.

[0121] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 0.00781 to about 256 mg / L, and zidovudine is used at a concentration of about 0.03125 to about 512 mg / L. In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 1 to about 256 mg / L, and zidovudine is used at a concentration of about 0.03125 to about 512 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 128 mg / L, and the zidovudine concentration may be about 0.03125 to about 512 mg / L. Most preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be from about 2 to about 32 mg / L, and the zidovudine concentration may be from about 0.03125 to about 128 mg / L, more preferably from 0.25 to about 128 mg / L.

[0122] In various embodiments, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, meropenem is used at a concentration of about 0.5 to about 4 mg / L, and zidovudine is used at a concentration of about 7.8 to about 1000 mg / L. Preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the meropenem concentration may be about 1 to about 4 mg / L, and the zidovudine concentration may be about 7.8 to about 1000 mg / L. More preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the meropenem concentration may be about 1 to about 4 mg / L, and the zidovudine concentration may be about 62.5 to about 1000 mg / L.

[0123] In various implementation schemes, the concentration of doxycycline is 1xMIC for the bacteria targeted by the combination used. 单 Or lower. Preferably, the concentration of doxycycline may be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of doxycycline may be 0.25 × MIC for the bacteria targeted by the combination used. 单 Or lower. Most preferably, the concentration of doxycycline is 0.125 × MIC for the bacteria targeted by the combination used. 单 Or lower.

[0124] As an example, in combinations that demonstrate a synergistic effect against MRSA, the concentration of doxycycline may be about 2 mg / L or lower, preferably about 0.03125 to about 2 mg / L.

[0125] In another instance, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, the concentration of doxycycline may be about 1 mg / L or less, preferably about 0.25 to about 1 mg / L.

[0126] In another instance, in combinations that demonstrate a synergistic effect against MSSA, the concentration of doxycycline may be about 2 mg / L or lower, preferably about 0.03125 to about 2 mg / L.

[0127] In another example, in combinations that demonstrate synergistic effects against Pseudomonas aeruginosa, the concentration of doxycycline may be about 2 mg / L or less, preferably about 0.5 to about 2 mg / L.

[0128] In another example, in combinations that demonstrate a synergistic effect against Klebsiella pneumoniae, the concentration of doxycycline may be about 2 mg / L or less, preferably about 0.03125 to about 2 mg / L.

[0129] As will be understood by those skilled in the art, the concentration range of doxycycline as a second antimicrobial agent can be combined with the concentration range of meropenem as a first antimicrobial agent, and further combined with the following concentration ranges of each of fosfomycin and levofloxacin as third antimicrobial agents as defined below. Those skilled in the art will also understand that all concentration ranges herein apply to pharmaceutically acceptable derivatives of the compounds.

[0130] In various embodiments, in combinations exhibiting synergistic effects against MRSA, meropenem is used at a concentration of about 1 to about 32 mg / L, and doxycycline is used at a concentration of about 0.03125 to about 2 mg / L. Preferably, in combinations exhibiting synergistic effects against MRSA, the meropenem concentration may be about 4 to about 32 mg / L, and the doxycycline concentration may be about 0.03125 to about 2 mg / L. Most preferably, in combinations exhibiting synergistic effects against MRSA, the meropenem concentration may be about 4 to about 32 mg / L, and the doxycycline concentration may be about 0.0625 to about 2 mg / L.

[0131] In various embodiments, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, meropenem is used at a concentration of about 0.125 to about 128 mg / L, and doxycycline is used at a concentration of about 2 to about 8 mg / L. Preferably, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be about 0.125 to about 32 mg / L, and the doxycycline concentration may be about 2 to about 8 mg / L.

[0132] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 0.00781 to about 256 mg / L, and doxycycline is used at a concentration of about 0.25 to about 1 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 0.00781 to about 128 mg / L, and the doxycycline concentration may be about 0.25 to about 1 mg / L. More preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 0.00781 to about 32 mg / L, and the doxycycline concentration may be about 0.25 to about 1 mg / L.

[0133] In various embodiments, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, meropenem is used at a concentration of about 0.5 to about 4 mg / L, and doxycycline is used at a concentration of about 0.003125 to about 2 mg / L. Preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the meropenem concentration may be about 1 to about 4 mg / L, and the doxycycline concentration may be about 0.003125 to about 2 mg / L.

[0134] In various implementations, among combinations that demonstrate a synergistic effect against MSSA, meropenem is used at a concentration of about 0.0313 to about 0.25 mg / L, and doxycycline is used at a concentration of about 0.0313 to about 2 mg / L.

[0135] In various implementation schemes, the concentration of fosfomycin can be 1xMIC for the bacteria targeted by the combination used. 单 Or lower. Preferably, the concentration of fosfomycin may be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of fosfomycin may be 0.25 × MIC for the bacteria targeted by the combination used. 单 Or lower. Most preferably, the concentration of fosfomycin is 0.125 × MIC for the bacteria targeted by the combination used. 单 Or lower.

[0136] As an example, in combinations that demonstrate synergistic effects against Pseudomonas aeruginosa, the concentration of fosfomycin may be about 128 mg / L or lower, preferably about 0.25 to about 128 mg / L, more preferably about 16 to about 128 mg / L.

[0137] As another example, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, the concentration of fosfomycin may be about 256 mg / L or lower, preferably about 0.5 to about 256 mg / L, more preferably about 32 to about 256 mg / L.

[0138] As another example, in combinations that demonstrate a synergistic effect against MRSA, the concentration of fosfomycin may be about 16 mg / L or lower, preferably about 0.03125 to about 16 mg / L, more preferably about 2 to about 16 mg / L.

[0139] As another example, in combinations that demonstrate synergistic effects against Klebsiella pneumoniae, the concentration of fosfomycin may be about 64 mg / L or lower, preferably about 8 to about 64 mg / L.

[0140] As another example, in combinations that show a synergistic effect against MSSA, the concentration of fosfomycin may be about 16 mg / L or less, preferably about 0.5 to about 16 mg / L, more preferably about 2 to about 16 mg / L.

[0141] As described above, the concentration range of fosfomycin can be combined with the concentration ranges of each of meropenem and zidovudine. In various embodiments, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, meropenem is used at a concentration of about 0.25 to about 128 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and fosfomycin at a concentration of 0.25 to about 128 mg / L, more preferably about 16 to about 128 mg / L. Preferably, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration can be about 4 to about 32 mg / L, the zidovudine concentration can be about 0.03125 to about 512 mg / L, and the fosfomycin concentration can be about 16 to about 128 mg / L. Most preferably, in the combination exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be from about 4 to about 32 mg / L, the zidovudine concentration may be from about 0.5 to about 128 mg / L, and the fosfomycin concentration may be from about 16 to about 128 mg / L.

[0142] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 1 to about 256 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and fosfomycin at a concentration of about 0.5 to about 256 mg / L, more preferably about 32 to about 256 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 128 mg / L, the zidovudine concentration may be about 0.03125 to about 512 mg / L, and the fosfomycin concentration may be about 32 to about 256 mg / L. Most preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 32 mg / L, the zidovudine concentration may be about 0.25 to about 128 mg / L, and the fosfomycin concentration may be about 32 to about 256 mg / L.

[0143] As described above, the concentration range of fosfomycin can be combined with the concentration ranges of each of meropenem and doxycycline. In various embodiments, in combinations exhibiting synergistic effects against MRSA, meropenem is used at a concentration of about 1 to about 32 mg / L, doxycycline at a concentration of about 0.03125 to about 2 mg / L, and fosfomycin at a concentration of about 0.03125 to about 16 mg / L, more preferably about 2 to about 16 mg / L. Preferably, in combinations exhibiting synergistic effects against MRSA, the concentration of meropenem can be about 4 to about 32 mg / L, the concentration of doxycycline can be about 0.03125 to about 2 mg / L, and the concentration of fosfomycin can be about 2 to about 16 mg / L. Most preferably, in combinations exhibiting synergistic effects against MRSA, the concentration of meropenem can be about 4 to about 32 mg / L, the concentration of doxycycline can be about 0.0625 to about 2 mg / L, and the concentration of fosfomycin can be about 2 to about 16 mg / L.

[0144] In various embodiments, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, meropenem is used at a concentration of about 0.5 to about 4 mg / L, doxycycline at a concentration of about 0.03125 to about 2 mg / L, and fosfomycin at a concentration of about 8 to about 64 mg / L. Preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the meropenem concentration may be about 1 to about 4 mg / L, the doxycycline concentration may be about 0.03125 to about 2 mg / L, and the fosfomycin concentration may be about 8 to about 64 mg / L.

[0145] In various embodiments, among combinations that demonstrate a synergistic effect against MSSA, meropenem is used at a concentration of about 0.0313 to about 0.25 mg / L, doxycycline is used at a concentration of about 0.03125 to about 2 mg / L, and fosfomycin is used at a concentration of about 0.5 to about 16 mg / L, more preferably about 2 to about 16 mg / L.

[0146] The concentration of each of meropenem, zidovudine, and fosfomycin can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Zidovudine can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and fosfomycin can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at a 1x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or at lower concentrations, and zidovudine can be used at 0.5 to 1x MIC.单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and zidovudine can be used at 1x MIC. 单 Or use at a lower concentration.

[0147] The concentration of each of meropenem, doxycycline, and fosfomycin can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and fosfomycin can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at a 1x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or at lower concentrations, and doxycycline can be used at 0.5 to 1x MIC. 单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and doxycycline can be used at 1x MIC. 单 Or use at a lower concentration.

[0148] In various implementation schemes, the concentration of levofloxacin can be 1xMIC for the bacteria targeted by the combination used. 单 Or lower. Preferably, the concentration of levofloxacin may be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of levofloxacin may be 0.25 × MIC for the bacteria targeted by the combination used. 单 Or lower. Most preferably, the concentration of levofloxacin is 0.125 × MIC for the bacteria targeted by the combination used. 单 Or lower.

[0149] As an example, in combinations that demonstrate a synergistic effect against MRSA, the concentration of levofloxacin may be about 1 mg / L or lower, preferably about 0.03125 to about 1 mg / L.

[0150] As described above, the concentration range of levofloxacin can be combined with the concentration ranges of each of meropenem and doxycycline. In various embodiments, in combinations exhibiting synergistic effects against MRSA, meropenem is used at a concentration of about 1 to about 2 mg / L, doxycycline at a concentration of about 0.03125 to about 2 mg / L, and levofloxacin at a concentration of about 0.03125 to about 1 mg / L. Preferably, in combinations exhibiting synergistic effects against MRSA, the meropenem concentration can be about 4 to about 32 mg / L, the doxycycline concentration can be about 0.03125 to about 2 mg / L, and the levofloxacin concentration can be about 0.03125 to about 1 mg / L. Most preferably, in the combination exhibiting a synergistic effect against MRSA, the meropenem concentration may be from about 4 to about 32 mg / L, the doxycycline concentration may be from about 0.0625 to about 2 mg / L, and the levofloxacin concentration may be from about 0.125 to about 1 mg / L.

[0151] The concentration of each of meropenem, zidovudine, and levofloxacin can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Zidovudine can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and levofloxacin can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at a 1x MIC. 单 Levofloxacin can be used at concentrations lower than 1x MIC. 单 Or at lower concentrations, and zidovudine can be used at 0.5 to 1x MIC. 单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Levofloxacin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and zidovudine can be used at 1x MIC. 单 Or use at a lower concentration.

[0152] The concentration of each of meropenem, doxycycline, and levofloxacin can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and levofloxacin can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at a 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC.单 Or at lower concentrations, and levofloxacin can be used at 0.5 to 1x MIC. 单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Levofloxacin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and doxycycline can be used at 1x MIC. 单 Or use at a lower concentration.

[0153] In various implementation schemes, the concentration of polymyxin E or polymyxin B against the bacteria targeted by the combination used can be 1x MIC. 单 Or lower. Preferably, the concentration of polymyxin E or polymyxin B may be 0.5 x MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of polymyxin E or polymyxin B may be 0.25 x MIC for the bacteria targeted by the combination used. 单 Or even lower. Most preferably, for the bacteria targeted by the combination used, the concentration of polymyxin E or polymyxin B can be 0.125 x MIC. 单 Or lower.

[0154] As an example, in combinations that demonstrate synergistic effects against Pseudomonas aeruginosa, the concentration of polymyxin E or polymyxin B may be about 512 mg / L or lower, preferably about 0.015625 to about 512 mg / L.

[0155] As another example, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, the concentration of polymyxin E or polymyxin B may be about 128 mg / L or lower, preferably about 0.016 to about 128 mg / L, more preferably about 1 to about 128 mg / L.

[0156] As another example, in combinations that demonstrate synergistic effects against Klebsiella pneumoniae, the concentration of polymyxin E or polymyxin B may be about 250 mg / L or lower, preferably about 62.5 to about 250 mg / L.

[0157] The concentration range of polymyxin E / B can be combined with the concentration range of each of meropenem and zidovudine mentioned above. Alternatively, the concentration range of polymyxin E / B can be combined with each of meropenem and doxycycline as defined herein.

[0158] In various embodiments, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, meropenem is used at a concentration of about 0.25 to about 128 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and polymyxin E / B at a concentration of about 0.015625 to about 512 mg / L. Preferably, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be about 4 to about 32 mg / L, the zidovudine concentration may be about 0.03125 to about 512 mg / L, and the polymyxin E / B concentration may be about 0.015625 to about 512 mg / L. Most preferably, in the combination exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be from about 4 to about 32 mg / L, the zidovudine concentration may be from about 0.25 to about 128 mg / L, and the polymyxin E / B concentration may be from about 0.015625 to about 512 mg / L, preferably from 0.03125 to about 4 mg / L.

[0159] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 1 to about 256 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and polymyxin E / B at a concentration of about 1 to about 128 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 128 mg / L, the zidovudine concentration may be about 0.03125 to about 512 mg / L, and the polymyxin E / B concentration may be about 1 to about 128 mg / L. Most preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 32 mg / L, the zidovudine concentration may be about 0.25 to about 128 mg / L, and the polymyxin E / B concentration may be about 1 to about 128 mg / L, preferably 2 to about 128 mg / L.

[0160] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 0.5 to about 4 mg / L, zidovudine at a concentration of about 7.8 to about 1000 mg / L, and polymyxin E / B at a concentration of about 62.5 to about 250 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 1 to about 4 mg / L, the zidovudine concentration may be about 7.8 to about 1000 mg / L, and the polymyxin E / B concentration may be about 62.5 to about 250 mg / L. More preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 1 to about 4 mg / L, the zidovudine concentration may be about 62.5 to about 1000 mg / L, and the polymyxin E / B concentration may be about 62.5 to about 250 mg / L.

[0161] The concentration of each of meropenem, zidovudine, and polymyxin E / B can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Zidovudine can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and polymyxin E / B can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at 1xMIC. 单 Polymyxin E / B can be used at concentrations lower than 1x MIC. 单 Or at lower concentrations, and zidovudine can be used at 0.5 to 1x MIC. 单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Polymyxin E / B can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and zidovudine can be used at 1x MIC. 单 Or use at a lower concentration.

[0162] The concentration of each of meropenem, polymyxin E / B, and polymyxin E / B can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and polymyxin E / B can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at 1xMIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单Or at lower concentrations, and polymyxin E / B can be used at 0.5 to 1x MIC. 单 Use at the specified concentration. Alternatively, meropenem can be administered at 0.5x MIC. 单 Polymyxin E / B can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and doxycycline can be used at 1x MIC. 单 Or use at a lower concentration.

[0163] In various embodiments, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, meropenem is used at a concentration of about 0.25 to about 128 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and colistin / polymyxin E at a concentration of about 0.015625 to about 512 mg / L. Preferably, in combinations exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be about 4 to about 32 mg / L, the zidovudine concentration may be about 0.03125 to about 512 mg / L, and the colistin / polymyxin E concentration may be about 0.015625 to about 512 mg / L. Most preferably, in the combination exhibiting synergistic effects against Pseudomonas aeruginosa, the meropenem concentration may be from about 4 to about 32 mg / L, the zidovudine concentration may be from about 0.25 to about 128 mg / L, and the colistin / polymyxin E concentration may be from about 0.015625 to about 512, preferably from about 0.03125 to about 4 mg / L.

[0164] In various embodiments, in combinations exhibiting synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 1 to about 256 mg / L, zidovudine at a concentration of about 0.03125 to about 512 mg / L, and colistin / polymyxin E at a concentration of about 1 to about 128 mg / L. Preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 128 mg / L, the zidovudine concentration may be about 0.03125 to about 512 mg / L, and the colistin / polymyxin E concentration may be about 1 to about 128 mg / L. Most preferably, in combinations exhibiting synergistic effects against Acinetobacter baumannii, the meropenem concentration may be about 2 to about 32 mg / L, the zidovudine concentration may be about 0.25 to about 128 mg / L, and the colistin / polymyxin E concentration may be about 2 to about 128 mg / L.

[0165] The concentration of each of meropenem, zidovudine, and colistin / polymyxin E can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单Zidovudine can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at 0.5x MIC. 单 Zidovudine can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. More preferably, meropenem can be used at 0.125x MIC. 单 Zidovudine can be used at concentrations of 0.125 to 1x MIC, or even lower. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. Most preferably, meropenem is used at 0.125x MIC. 单 Zidovudine can be used at concentrations ranging from 0.125 to 1x MIC. 单 The concentration used, and colistin / polymyxin E can be used at 1x MIC 单 Or use at a lower concentration.

[0166] In various implementation schemes, the concentration of ceftazidime can be 1xMIC for the bacteria targeted by the combination used. 单 Or lower. Preferably, the concentration of ceftazidime may be 0.5 × MIC for the bacteria targeted by the combination used. 单 Or lower. More preferably, the concentration of ceftazidime may be 0.25 × MIC for the bacteria targeted by the combination used. 单 Or even lower. Most preferably, the concentration of ceftazidime can be 0.125 × MIC for the bacteria targeted by the combination used. 单 Or lower.

[0167] As an example, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, the concentration of ceftazidime may be about 0.5 mg / L or lower, preferably about 0.01563 to about 0.5 mg / L.

[0168] As an example, in combinations that show synergistic effects against Pseudomonas aeruginosa, the concentration of ceftazidime may be about 4 mg / L or lower, preferably about 0.00391 to about 4 mg / L.

[0169] As an example, in combinations that demonstrate synergistic effects against Klebsiella pneumoniae, the concentration of ceftazidime may be about 32 mg / L or lower, preferably about 0.5 to about 32 mg / L.

[0170] As an example, in combinations that demonstrate a synergistic effect against MSSA, the concentration of ceftazidime may be about 16 mg / L or lower, preferably about 0.25 to about 16 mg / L.

[0171] The concentration range of ceftazidime can be combined with the concentration ranges of each of meropenem, doxycycline, and fosfomycin. In various embodiments, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 0.03 to about 0.007813 mg / L, doxycycline at a concentration of about 0.25 to about 1 mg / L, fosfomycin at a concentration of about 2 to about 32 mg / L, and ceftazidime at a concentration of about 0.01563 to about 0.5 mg / L.

[0172] In various embodiments, among combinations that demonstrate synergistic effects against Pseudomonas aeruginosa, meropenem is used at a concentration of about 0.25 to about 0.5 mg / L, doxycycline at a concentration of about 2 to about 8 mg / L, fosfomycin at a concentration of about 4 to about 16 mg / L, and ceftazidime at a concentration of about 0.00391 to about 4 mg / L.

[0173] In various embodiments, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, meropenem is used at a concentration of about 0.5 to about 4 mg / L, doxycycline at a concentration of about 0.03125 to about 2 mg / L, fosfomycin at a concentration of about 8 to about 64 mg / L, and ceftazidime at a concentration of about 0.5 to about 32 mg / L. Preferably, in combinations exhibiting synergistic effects against Klebsiella pneumoniae, the concentration of meropenem may be about 1 to about 4 mg / L, the concentration of doxycycline may be about 0.03125 to about 2 mg / L, the concentration of fosfomycin may be about 8 to about 64 mg / L, and the concentration of ceftazidime may be about 0.5 to about 32 mg / L.

[0174] In various embodiments, among combinations that demonstrate a synergistic effect against MSSA, meropenem is used at a concentration of about 0.0313 to about 0.25 mg / L, doxycycline at a concentration of about 0.03125 to about 2 mg / L, fosfomycin at a concentration of about 0.5 to about 16 mg / L, more preferably about 2 to about 16 mg / L, and ceftazidime at a concentration of about 0.5 to about 32 mg / L.

[0175] The concentration of each of meropenem, doxycycline, fosfomycin, and ceftazidime can also be expressed as MIC. 单 Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC.单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and ceftazidime can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at 0.5x MIC. 单 Doxycycline can be used at concentrations lower than 1xMIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and ceftazidime can be used at 1xMIC. 单 Or at lower concentrations. More preferably, meropenem can be used at 0.125x MIC. 单 Doxycycline can be used at concentrations of 0.125 to 1x MIC, or even lower. 单 Fosfomycin can be used at concentrations of 0.125 to 1x MIC, or even lower. 单 Or use at lower concentrations, and ceftazidime can be used at 1x MIC. 单 Or at lower concentrations. Most preferably, meropenem is used at 0.125xMIC. 单 When used at concentrations, doxycycline can be administered at doses ranging from 0.125 to 1x MIC. 单 Fosfomycin can be used at concentrations ranging from 0.125 to 1xMIC. 单 The concentration at which ceftazidime is used, and the fact that ceftazidime can be used at 1x MIC 单 Or use at a lower concentration.

[0176] The concentration range of colistin / polymyxin E can be combined with the concentration range of each of meropenem, doxycycline, and fosfomycin. In various embodiments, in combinations that demonstrate synergistic effects against Acinetobacter baumannii, meropenem is used at a concentration of about 0.007813 to about 0.03 mg / L, doxycycline at a concentration of about 0.25 to about 1 mg / L, fosfomycin at a concentration of about 2 to about 32 mg / L, and colistin / polymyxin E at a concentration of about 0.016 to about 2 mg / L.

[0177] In various implementations, among combinations demonstrating synergistic effects against Klebsiella pneumoniae, meropenem is used at a concentration of about 0.5 to about 4 mg / L, doxycycline at a concentration of about 0.25 to about 2 mg / L, fosfomycin at a concentration of about 8 to about 64 mg / L, and colistin / polymyxin E at a concentration of about 62.5 to about 250 mg / L.

[0178] The concentration of each of meropenem, doxycycline, fosfomycin, and colistin / polymyxin E can also be expressed as MIC. 单Multiples of MIC. For example, meropenem can be used at 1x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. Preferably, meropenem can be used at 0.5x MIC. 单 Doxycycline can be used at concentrations lower than 1x MIC. 单 Fosfomycin can be used at concentrations lower than 1x MIC. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. More preferably, meropenem can be used at 0.125xMIC. 单 Doxycycline can be used at concentrations of 0.125 to 1x MIC, or even lower. 单 Fosfomycin can be used at concentrations of 0.125 to 1x MIC, or even lower. 单 Or use at lower concentrations, and colistin / polymyxin E can be used at 1x MIC. 单 Or at lower concentrations. Most preferably, meropenem is used at 0.125x MIC. 单 When used at concentrations, doxycycline can be administered at doses ranging from 0.125 to 1x MIC. 单 Fosfomycin can be used at concentrations ranging from 0.125 to 1x MIC. 单 The concentration used, and colistin / polymyxin E can be used at 1xMIC 单 Or use at a lower concentration.

[0179] MIC as defined in this article 单 The lower limit of the range is not limited. When no lower limit is specified, it is preferably 1 / 512 MIC. 单 1 / 256 MIC 单 1 / 128 MIC 单 1 / 64 MIC 单 1 / 32 MIC 单 Or 0.0625 MIC 单 For example, "0.5 x MIC" 单 "or lower" becomes "0.5x MIC" 单 Up to 0.0625 MIC 单 ".

[0180] As described herein, in various embodiments, the combinations of the present invention exhibit synergistic effects against Gram-negative and / or Gram-positive bacteria. Therefore, in further embodiments, any concentration range specified in the preceding paragraphs can be combined with combinations that exhibit synergistic effects against Gram-negative and / or Gram-positive bacteria. For example, in any of the foregoing embodiments, combinations having any of the aforementioned concentration ranges can exhibit synergistic effects against Enterobacteriaceae, Acinetobacter spp., Pseudomonas spp., and / or Staphylococcus spp.

[0181] Formulations suitable for oral administration may exist in the form of discrete units, such as capsules, flat capsules, or tablets (e.g., chewable tablets specifically for pediatric use), each unit containing a predetermined amount of the active ingredient; in the form of powder or granules; in the form of a solution or suspension in an aqueous or non-aqueous liquid; or in the form of an oil-in-water emulsion or a water-in-oil emulsion. The active ingredient may also exist in the form of pills, ointments, or pastes.

[0182] Tablets can be prepared by compression or molding, and optionally contain one or more excipients. Compressed tablets can be prepared by compressing the active ingredient (e.g., powder or granules) in a free-flowing form in a suitable machine, optionally mixed with other conventional excipients such as binders (e.g., syrup, gum arabic, gelatin, sorbitol, tragacanth gum, starch slurry, polyvinylpyrrolidone, and / or hydroxymethyl cellulose), fillers (e.g., lactose, sugar, microcrystalline cellulose, corn starch, calcium phosphate, and / or sorbitol), lubricants (e.g., magnesium stearate, stearic acid, talc, polyethylene glycol, and / or silica), disintegrants (e.g., potato starch, croscarmellose sodium, and / or starch glycolate sodium), and wetting agents (e.g., sodium lauryl sulfate). Molded tablets can be prepared by molding a mixture of powdered active ingredient and an inert liquid diluent in a suitable machine. Tablets can optionally be coated or scored and can be formulated to provide controlled release of the active ingredient (e.g., delayed, sustained, or pulsatile release, or a combination of immediate and controlled release).

[0183] Alternatively, the active ingredient can be incorporated into oral liquid formulations, such as aqueous or oily suspensions, solutions, emulsions, syrups, or elixirs. Formulations containing the active ingredient can also exist as dry products, ready for reconstitution with water or another suitable medium prior to use.

[0184] Such liquid formulations may contain conventional additives such as suspending agents (e.g., sorbitol syrup, methylcellulose, glucose / syrup, gelatin, carboxymethylcellulose, aluminum stearate gel and / or hydrogenated edible fats), emulsifiers (e.g., lecithin, dehydrated sorbitol monooleate and / or gum arabic), non-aqueous mediators (e.g., edible oils such as almond oil, fractionated coconut oil, oily esters, propylene glycol and / or ethanol), and preservatives (e.g., methylparaben or propylparaben and / or sorbic acid).

[0185] The combinations according to the invention can be contained in packaging or dispenser devices that may include one or more unit dosage forms containing active ingredients. The packaging may, for example, contain metal or plastic foil, such as blister packs. When the compositions are intended to be administered as three separate compositions, they can be present in a dual-pack.

[0186] Pharmaceutical compositions can also be prescribed to patients in “patient packs,” which contain the entire course of medication in a single package, typically a blister pack. Patient packs offer advantages over traditional prescriptions, where pharmacists need to repackage the medication from a bulk supply for the patient. The advantage of patient packs is that patients can always access the information included in the package, which is often absent in traditional prescriptions. Including informational materials has been shown to improve patient adherence to medication orders.

[0187] The ideal feature of this invention is to administer the combinations of the invention through individual patient packages or patient packages of each composition (including instructions for patients on the proper use of the invention).

[0188] According to another embodiment of the invention, a patient package is provided comprising at least one active ingredient of the combination according to the invention and an information insert containing instructions for use of the combination of the invention. In another embodiment of the invention, a dual package is provided comprising, in a combined manner, an antimicrobial agent (preferably having bioactivity against clinically latent microorganisms) for separate administration, and one or more compounds disclosed herein (preferably having bioactivity against clinically latent microorganisms).

[0189] The amount of active ingredient required for treatment will vary depending on the nature of the condition being treated and the patient's age and condition, and will ultimately be determined by the attending physician. However, generally, the dosage range for adult treatment is typically 0.02 to 5000 mg daily, preferably 1 to 1500 mg daily. The required dosage can be conveniently provided as a single dose or in divided doses administered at appropriate intervals, such as sub-dose twice, three, or more times daily.

[0190] Therefore, those skilled in the art will readily obtain and understand the information described herein. Biological tests

[0191] Test procedures that can be used to determine the biological (e.g., bactericidal or antimicrobial) activity of an active ingredient include test procedures known to those skilled in the art for determining the following: (a) Bactericidal activity against clinically latent bacteria; and (b) Antimicrobial activity against logarithmic bacteria.

[0192] Regarding (a) above, methods for determining activity against clinically latent bacteria include determining the minimum stationary-cidal concentration (“MSC”) or minimum dormant concentration (“MDC”) of the test compound, under conditions known to those skilled in the art (such as those described in Nature Reviews, Drug Discovery 1, 895-910 (2002), the disclosure of which is incorporated herein by reference).

[0193] For example, WO2000028074 describes a suitable method for screening compounds to determine their ability to kill clinically latent microorganisms. A typical method may include the following steps: (1) Culture the bacterial culture to the stationary phase; (2) Select phenotypic resistant subgroups by treating stationary cultures with one or more antimicrobial agents at concentrations and / or times sufficient to kill growing bacteria. (3) Incubate the sample of the phenotypic resistance subgroup with one or more test compounds or reagents; and (4) Evaluate any antimicrobial effects against phenotypic resistant subgroups.

[0194] According to this method, phenotypic resistant subgroups can be considered as representatives of clinically latent bacteria that maintain metabolic activity in vivo and can lead to disease relapse or onset.

[0195] Regarding (b) above, methods for determining activity against logarithmic-phase bacteria include determining the minimum inhibitory concentration (“MIC”) or minimum bactericidal concentration (“MBC”) of the test compound under standard conditions (i.e., conditions known to those skilled in the art, such as those described in WO 2005014585, the disclosure of which is incorporated herein by reference). Specific examples of these methods are described below. Example

[0196] Antimicrobial agents were purchased from commercial sources. They were weighed and dissolved in water, PBS, DMSO, or acidified water to prepare a final concentration of 1–10 mg / mL. The antimicrobial solution was diluted 10 times to the highest concentration used in the experiment, followed by serial dilutions of 2-fold, with a maximum of 11 dilutions. In this way, the operator could obtain up to 12 different concentrations of the selected antimicrobial agent in a decreasing gradient.

[0197] The bacteria were obtained from Ninewells Hospital and Medical School in Dundee, Scotland. They were obtained as patient strains and characterized by Vitek 2 screening. To prepare for the examples below, the bacteria were grown overnight in cationic-regulated Mueller Hinton broth, or until confluence in media with or without supplementation. The OD of the bacteria was measured. 600 Bacteria with readings < 0.25 were returned to the incubator. The bacterial cultures were diluted in culture medium to an OD value of [missing value]. 600 A reading ≤ 0.01 indicates a culture concentration of approximately 10-1. 6 CFU / ml.

[0198] All data in this article were generated using the same chessboard.

[0199] Pipe 20 μL of antibiotic A (baseline) at a single dilution into all wells of the 96-well plate to be used.

[0200] Pipe 20 μL of the lowest concentration of antibiotic B (first variable) into column 1 of a 96-well plate. Pipe the second concentration (more than 2 times the concentration) into column 2. Repeat this process until all the remaining concentrations of antibiotic B have been used.

[0201] Pipe 20 μL of the lowest concentration of antibiotic C (second variable) into row A of a 96-well plate. Pipe the second concentration (more than 2 times the concentration) into row B. Repeat this process until all the desired concentration of antibiotic C has been used.

[0202] Add 120 μL of sterile culture medium (BHI / MHB2).

[0203] Add 20 μL of the prepared bacterial culture.

[0204] Seal the plate with a lid and incubate for 16 hours, then overnight.

[0205] In a 96-well plate reader, at OD 600 Readings. These are the values ​​reported in the chessboard below.

[0206] For 3-mer combinations, the concentrations of two antibiotics are varied while one is kept constant; the latter is the "backbone." This method, along with the calculation of FICI and indicators of synergistic, indifferential, and antagonistic effects, is explained above. Example 1: Synergistic effect of zidovudine (AZT), fosfomycin, and meropenem (mero)

[0207] The triple combination of zidovudine, fosfomycin, and meropenem was tested in the above experiments. Fosfomycin at 16 mg / L (1 / 8 MIC) served as the backbone, and the combination was tested against *Pseudomonas aeruginosa*. The isolate exhibited resistance to ceftazidime up to at least 512 mg / L, resistance to colistin up to at least 512 mg / L, resistance to fosfomycin up to and including 64 mg / L, resistance to meropenem up to and including 64 mg / L, and resistance to AZT up to at least 512 mg / L. AZT (zidovudine-x axis) and meropenem (mero-y axis) were used at the following concentrations (mg / L):

[0208] The results reported in the table above (the corresponding checkerboard table in subsequent embodiments is similar) are reported as OD relative to the positive control. 600 The percentage of bacteria killed.

[0209] The bold values ​​in the table above (the corresponding checkerboard table in subsequent embodiments is similar) represent bacterial growth that is considered to represent ineffective bacterial killing (i.e., lack of synergistic effect).

[0210] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.157 and FIC = 0.105. This demonstrates the synergistic effect described above.

[0211] The triple combination of zidovudine, fosfomycin, and meropenem was also tested against Acinetobacter baumannii using fosfomycin at a concentration of 32 mg / L (1 / 8 MIC) as a backbone. This isolate exhibited resistance to ceftazidime up to at least 512 mg / L, resistance to colistin up to and including 64 mg / L, resistance to fosfomycin up to and including 128 mg / L, resistance to meropenem up to and including 128 mg / L, and resistance to zidovudine up to at least 512 mg / L. Zidovudine (x-axis) and meropenem (y-axis) were used at the following concentrations (mg / L): The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.133 and FIC = 0.0889. This demonstrates the synergistic effect described above. Example 2: Synergistic effect of zidovudine (AZT), colistin (CSS), and meropenem (mero)

[0212] The triple combination of zidovudine, colistin, and meropenem was tested in the above experiments. Meropenem at 4 mg / L (1 / 8 MIC) served as the backbone, and the combination was tested against *Pseudomonas aeruginosa*. The *Pseudomonas aeruginosa* isolates were the same as those used in Example 1. Colistin (CSS-x axis) and zidovudine (AZT-y axis) were used at the following concentrations (mg / L): The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.129 and FIC = 0.0860. This demonstrates the synergistic effect described above.

[0213] The triple combination of zidovudine, colistin, and meropenem was also tested against Acinetobacter baumannii using 8 mg / L (1 / 32 MIC) meropenem as a backbone. This isolate was the same as that used in Example 1. Zidovudine (y-axis) and colistin (CSS-x-axis) were used at the following concentrations (mg / L): The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.0664 and FIC = 0.0443. This demonstrates the synergistic effect described above.

[0214] The triple combination of zidovudine, colistin, and meropenem was also tested against Klebsiella pneumoniae CPE ESBL using 0.5 mg / L (1 / 8 MIC) meropenem as a backbone. This isolate was the same as that used in Example 1. Zidovudine (x-axis) and colistin (CSS-y-axis) were used at the following concentrations (mg / L): The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.438 and FIC = 0.292. This demonstrates the synergistic effect described above. Example 3: Synergistic effect among fosfomycin, meropenem, and doxycycline

[0215] A triple combination of fosfomycin, meropenem, and doxycycline was tested in the above experiments. Fosfomycin at 2 mg / L (1 / 8 MIC) served as the backbone, and the combination was tested against methicillin-resistant Staphylococcus aureus (MRSA). In each experiment, the highest concentration was equal to 1xMIC of the tested isolate. Meropenem (mero-y axis) and doxycycline (doxy-x axis) were used at the following concentrations (mg / L): The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.406 and FIC = 0.271. This demonstrates the synergistic effect described above.

[0216] The triple combination of fosfomycin, meropenem, and doxycycline was also tested against Klebsiella pneumoniae CPE ESBL using 1 mg / L (1 / 4 MIC) meropenem as a backbone. This isolate was the same as that used in Example 1. The following concentrations (mg / L) of doxycycline (x-axis) and fosfomycin (CSS-y-axis) were used: The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.383 and FIC = 0.255. This demonstrates the synergistic effect described above.

[0217] The triple combination of fosfomycin, meropenem, and doxycycline was also tested against methicillin-sensitive Staphylococcus aureus (MSSA) using meropenem at a concentration of 0.3125 mg / L (1 / 8 MIC) as the backbone. The isolate was determined to be resistant to meropenem (inferred from cefoxitin) and sensitive to doxycycline according to EUCASE 2024 (v.14). The following concentrations (mg / L) of doxycycline (x-axis) and fosfomycin (fosfo-y-axis) were used: The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.281 and FIC = 0.188. This demonstrates the synergistic effect described above. Example 4: Synergistic effect between meropenem (mero), levofloxacin (levo), and doxycycline (doxy)

[0218] The triple combination of meropenem, levofloxacin, and doxycycline was tested in the above experiments. Meropenem at 4 mg / L (1 / 8 MIC) served as the backbone, and the combination was tested against MRSA. In each experiment, the highest concentration was equal to 1xMIC of the tested isolate. Doxycycline (doxy-x axis) and levofloxacin (levo-y axis) were used at the following concentrations (mg / L):

[0219] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.375 and FIC = 0.250. This demonstrates the synergistic effect described above. Example 5: Synergistic effect among meropenem (mero), doxycycline (doxy), ceftazidime (cefta), and fosfomycin (fosfo)

[0220] A quadruple combination of meropenem, doxycycline, ceftazidime, and fosfomycin was tested in the above experiments. The efficacy of the combination was tested against *Acinetobacter baumannii* using 0.0078125 mg / L (0.26 × MIC) of meropenem and 0.25 mg / L (1 / 4 MIC) of doxycycline as the backbone. In each experiment, the highest concentration was equal to 1xMIC of the tested isolate. Ceftazidime (x-axis) and fosfomycin (fosfo-y-axis) were used at the following concentrations (mg / L):

[0221] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.604 and FIC = 0.302. This demonstrates the synergistic effect described above.

[0222] A quadruple therapy of meropenem, doxycycline, ceftazidime, and fosfomycin was also tested against Klebsiella pneumoniae using 0.5 mg / L (1 / 8 MIC) meropenem and 0.5 mg / L (1 / 4 MIC) doxycycline as the backbone. This isolate was the same as that used in Example 1. Ceftazidime (x-axis) and fosfomycin (y-axis) were used at the following concentrations (mg / L):

[0223] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.516 and FIC = 0.256. This demonstrates the synergistic effect described above.

[0224] A quadruple combination of meropenem, doxycycline, ceftazidime, and fosfomycin was also tested against *Pseudomonas aeruginosa* using 0.125 mg / L (1 / 4 MIC) meropenem and 2 mg / L (1 / 4 MIC) doxycycline as a backbone. This isolate was the same as that used in Example 1. Ceftazidime (x-axis) and fosfomycin (y-axis) were used at the following concentrations (mg / L):

[0225] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.751 and FIC = 0.375. This demonstrates the synergistic effect described above.

[0226] A quadruple combination of meropenem, doxycycline, ceftazidime, and fosfomycin was also tested against MSSA using 0.03125 mg / L (1 / 8 MIC) meropenem and 0.03125 mg / L (1 / 4 MIC) doxycycline as the backbone. This isolate was the same as that used in Example 3. Ceftazidime (x-axis) and fosfomycin (fosfo-y-axis) were used at the following concentrations (mg / L):

[0227] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.422 and FIC = 0.211. This demonstrates the synergistic effect described above. Example 6: Synergistic effect among meropenem (mero), doxycycline (doxy), colistin (CSS), and fosfomycin (fosfo)

[0228] A quadruple combination of meropenem, doxycycline, colistin, and fosfomycin was tested in the above experiments. The efficacy of the combination was tested against *Acinetobacter baumannii* using 0.0078125 mg / L (0.26xMIC) of meropenem and 0.25 mg / L (1 / 4 MIC) of doxycycline as the backbone. In each experiment, the highest concentration was equal to 1xMIC of the tested isolate. The following concentrations (mg / L) of colistin (CSS-x axis) and fosfomycin (fosfo-y axis) were used:

[0229] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.581 and FIC = 0.290. This demonstrates the synergistic effect described above.

[0230] A quadruple therapy of meropenem, doxycycline, colistin, and fosfomycin was also tested against Klebsiella pneumoniae using 0.5 mg / L (1 / 8 MIC) of meropenem and 0.25 mg / L (1 / 8 MIC) of doxycycline as a backbone. This isolate was the same as that used in Example 1. Colistin (CSS-x axis) and fosfomycin (fosfo-y axis) were used at the following concentrations (mg / L):

[0231] The MICs for each drug individually and in combination were calculated using the method described above. ΣFIC = 0.625 and FIC = 0.313. This demonstrates the synergistic effect described above.

[0232] These embodiments support the synergistic effect of the combinations of the present invention. When antimicrobial agents are combined, synergy is not the expected result, especially when three antimicrobial agents are combined and / or targeted at bacteria (such as the bacterial species tested herein). These embodiments support the synergistic effect of the combinations of the present invention against both Gram-negative and Gram-positive bacteria, thereby providing a solution to the global problem of antimicrobial resistance described above. This is a significant advancement in the art.

[0233] The various embodiments described herein are merely intended to aid in understanding and teaching the claimed features. These embodiments are provided only as representative examples of embodiments and are not exhaustive and / or exclusive. It should be understood that the advantages, embodiments, examples, functions, features, structures, and / or other aspects described herein should not be considered as limitations on the scope of the invention as defined by the claims or on the equivalents of the claims, and other embodiments may be utilized and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the invention may suitably include, constitute, or substantially constitute all of the disclosed elements, components, features, parts, steps, devices, etc., other than those specifically described herein. Furthermore, this disclosure may include other inventions not currently claimed but which may be claimed in the future.

Claims

1. An antimicrobial combination comprising three antimicrobial agents, wherein: i. The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof; ii. The second antimicrobial agent is selected from zidovudine, doxycycline, and their pharmaceutically acceptable derivatives; and iii. The third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B and their pharmaceutically acceptable derivatives; The condition is that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof.

2. The combination according to claim 1, wherein the second antimicrobial agent is zidovudine or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, polymyxin E, polymyxin B, and pharmaceutically acceptable derivatives thereof.

3. The combination according to claim 1, wherein the second antimicrobial agent is doxycycline or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, levofloxacin and pharmaceutically acceptable derivatives thereof.

4. The combination according to claim 2, wherein the third antimicrobial agent is selected from fosfomycin, polymyxin E, and pharmaceutically acceptable derivatives thereof.

5. The combination according to claim 3, wherein the third antimicrobial agent is fosfomycin or a pharmaceutically acceptable derivative thereof.

6. The combination according to claim 5, wherein the combination further comprises a fourth antimicrobial agent selected from ceftazidime, polymyxin E, and pharmaceutically acceptable derivatives thereof.

7. The combination according to any one of claims 1, 2, 4 or 6, wherein the pharmaceutically acceptable derivative of said polymyxin E is colistin sulfate, colistin mesylate or sodium colistin mesylate.

8. The combination according to any one of claims 1 to 7, for treating infections caused by Gram-negative or Gram-positive bacteria.

9. A pharmaceutical composition comprising the combination of any one of claims 1 to 8 and a pharmaceutically acceptable adjuvant, diluent, or carrier.

10. The pharmaceutical composition according to claim 9, for treating infections caused by Gram-negative or Gram-positive bacteria.

11. The combination according to claim 8, or the pharmaceutical composition according to claim 10, wherein the infection is a urinary tract infection, skin and soft tissue infection, intra-abdominal infection, upper respiratory tract infection, pneumonia, or bloodstream infection.

12. The combination according to claim 8 or claim 11, or the pharmaceutical composition according to claim 9 or claim 10, wherein the infection is caused by Enterobacteriaceae, Acinetobacter, Pseudomonas, or Staphylococcus.

13. The combination or pharmaceutical composition according to claim 12, wherein the infection is caused by Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, MSSA, or MRSA.

14. The combination or pharmaceutical composition according to claim 12, wherein the infection is caused by Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, or MRSA.

15. The combination of any one of claims 8 or 11 to 14, or the pharmaceutical composition of any one of claims 10 to 14, wherein the infection is caused by a drug-resistant strain of bacteria.

16. A product comprising an antimicrobial combination of three antimicrobial agents, wherein: i. The first antimicrobial agent is meropenem or a pharmaceutically acceptable derivative thereof; ii. The second antimicrobial agent is selected from zidovudine, doxycycline, and their pharmaceutically acceptable derivatives; and iii. The third antimicrobial agent is selected from fosfomycin, levofloxacin, polymyxin E, polymyxin B and their pharmaceutically acceptable derivatives; The condition is that the combination is not (i) meropenem or a pharmaceutically acceptable derivative thereof, (ii) doxycycline or a pharmaceutically acceptable derivative thereof, and (iii) polymyxin E / B or a pharmaceutically acceptable derivative thereof; as a combination preparation used simultaneously, separately, or sequentially for the treatment of infections caused by Gram-negative or Gram-positive bacteria.

17. The product according to claim 16, wherein the second antimicrobial agent is zidovudine or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, polymyxin E, polymyxin E and pharmaceutically acceptable derivatives thereof.

18. The product according to claim 16, wherein the second antimicrobial agent is doxycycline or a pharmaceutically acceptable derivative thereof, and the third antimicrobial agent is selected from fosfomycin, levofloxacin and pharmaceutically acceptable derivatives thereof.

19. The product according to claim 17, wherein the third antimicrobial agent is selected from fosfomycin, polymyxin E, and pharmaceutically acceptable derivatives thereof.

20. The product of claim 18, wherein the third antimicrobial agent is fosfomycin or a pharmaceutically acceptable derivative thereof.

21. The combination of claim 20, wherein the combination further comprises a fourth antimicrobial agent selected from ceftazidime, polymyxin E, and pharmaceutically acceptable derivatives thereof.

Images