Patent application title: Chlorhexadine Antiseptic
Inventors:
Victor Carnell (Spokane, WA, US)
Christopher Herzog (Spokane, WA, US)
Assignees:
CARNELL & HERZOG, LLC
IPC8 Class: AA61K31155FI
USPC Class:
514635
Class name: Amidines (i.e., n=c-n) guanidines (i.e., n=c(-n)-n) biguanides (i.e., n=c(-n)-n(n-)c=n)
Publication date: 2014-09-18
Patent application number: 20140275275
Abstract:
A composition comprising a mixture of chlorohexidine, a surfactant, and a
cationic quaternary ammonium compound is suitable for use as an
antiseptic and is surprisingly effective against difficult-to-kill
organisms such as Mycobacterium tuberculosis and against
Methicillin-resistant Staphylococcus aureus (MRSA) while still being
suitable for topical application. The composition may include a chelating
agent.Claims:
1. A composition comprising: chlorhexidine or a salt thereof present at
about 0.96 weight/volume %; N-acyl sarcosinate present at about 0.05
weight/volume %; and one or more cetylpyridinium salts present at about
0.1 weight/volume %.
2. The composition of claim 1, wherein the chlorhexidine comprises a gluconate salt.
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. The composition of claim 1, wherein the one or more cetylpyridinium salts comprise cetylpyridinium chloride (CPC), cetylpyridinium bromide, or mixtures thereof.
11. (canceled)
12. (canceled)
13. The composition of claim 1, further comprising one or more chelating agents.
14. The composition of claim 13, wherein the one or more chelating agents comprise ethylenediaminetetraacetic acid (EDTA).
15. The composition of claim 13, wherein the one or more chelating agents are present at about 0.1 to about 0.5 weight/volume %.
16. A composition consisting of: a solvent; chlorhexidine or a salt thereof present at about 0.4 to about 5 weight/volume %; a sarcosinate surfactant present at about 0.01 to about 1 weight/volume %; a cationic quaternary ammonium compound present at about 0.1 to about 1 weight/volume %; and one or more chelating agents.
17. A method of killing or inactivating microorganisms present on tissue of a patient, the method comprising: contacting the tissue of the patient with a composition according to claim 1.
18. (canceled)
19. (canceled)
20. (canceled)
21. The composition of claim 16, wherein the solvent comprises water or a saline solution.
22. The composition of claim 16, wherein the chlorhexidine or salt thereof comprises a gluconate salt.
23. The composition of claim 16, wherein the sarcosinate surfactant comprises N-acyl sarcosinate.
24. The composition of claim 16, wherein the cationic quaternary ammonium compound comprises cetylpyridinium chloride (CPC), cetylpyridinium bromide, or mixtures thereof.
25. The composition of claim 16, wherein the one or more chelating agents are selected from the group comprising ethylenediaminetetraacetic acid (EDTA); diethylenetriaminepentaacetic acid (DPTA); Aminotrimethylene phosphonic acid, Beta-Alanine Diacetic Acid, Calcium Disodium ethylenediaminetetraacetic acid (EDTA), Citric Acid, Cyclodextrin, Cyclohexanediamine Tetraacetic Acid, Diammonium Citrate, Diammonium EDTA, Diethylenetriamine Pentamethylene Phosphonic Acid, Dipotassium EDTA, Disodium Azacycloheptane Diphosphonate, Disodium EDTA, Disodium Pyrophosphate, EDTA, Etidronic Acid (HEDP, Hydroxyethylidene diphosphonic acid), Galactaric Acid, Gluconic Acid, Glucuronic Acid, HEDTA, Hydroxypropyl Cyclodextrin, Methyl Cyclodextrin, Pentapotassium Triphosphate, Methyl glycine diacetic acid (MGDA), Pentasodium Aminotrimethylene Phosphonate, Pentasodium Ethylenediamine Tetramethylene Phosphonate, Pentasodium Pentetate, Pentasodium Triphosphate, Pentetic Acid, Phytic Acid, Polyamine, Potassium Citrate, Potassium EDTMP, Potassium Gluconate, Potassium Polyphosphate, Potassium Trisphosphonomethylamine Oxide, Ribonic Acid, Sodium Chitosan Methylene Phosphonate, Sodium Citrate, Sodium Diethylenetriamine Pentamethylene Phosphonate, Sodium Dihydroxyethylglycinate, Sodium EDTMP, Sodium Gluceptate, Sodium Gluconate, Sodium Glycereth-1 Polyphosphate, Sodium Hexametaphosphate, Sodium Metaphosphate, Sodium Metasilicate, Sodium Phytate, Sodium Polydimethylglycinophenolsulfonate, Sodium Trimetaphosphate, TEA-EDTA, TEA-Polyphosphate, Tetrahydroxyethyl Ethylenediamine, Tetrahydroxypropyl Ethylenediamine, Tetrapotassium Etidronate, Tetrapotassium Pyrophosphate, Tetrasodium EDTA, Tetrasodium Etidronate, Tetrasodium Pyrophosphate, Tripotassium EDTA, Trisodium Dicarboxymethyl Alaninate, Trisodium EDTA, Trisodium HEDTA, Trisodium MGDA, Trisodium N, N-bis(carboxymethyl)glycine (NTA), and Trisodium Phosphate.
26. A method of disinfecting tissue of a patient, the method comprising: contacting the tissue of the patient with a composition according to claim 16.
27. A composition consisting essentially of: a solvent; chlorhexidine or a salt thereof present at about 0.4 to about 5 weight/volume %; N-acyl sarcosinate present at about 0.01 to about 1 weight/volume %; and one or more cetylpyridinium salts present at about 0.1 to about 1 weight/volume %, wherein the composition reduces a Mycobacterium smegmatis population by about 75% after about one minute of exposure.
28. the composition of claim 27, wherein the chlorhexidine or salt thereof is present at about 0.96 weight/volume %, the N-acyl sarcosinate is present at about 0.05 weight/volume %, and the one or more cetylpyridinum salts are present at about 0.1 weight/volume %.
29. A method of killing or inactivating microorganisms present on tissue of a patient, the method comprising: contacting the tissue of the patient with a composition according to claim 27.
30. A composition consisting essentially of: a solvent; chlorhexidine or a salt thereof present at about 0.4 to about 5 weight/volume %; N-acyl sarcosinate present at about 0.01 to about 1 weight/volume %; one or more cetylpyridinium salts present at about 0.1 to about 1 weight/volume %; and ethylenediaminetetraacetic acid (EDTA), wherein the composition reduces a Mycobacterium smegmatis population by about 80% after about one minute of exposure.
31. the composition of claim 30, wherein the chlorhexidine or salt thereof is present at about 0.96 weight/volume %, the N-acyl sarcosinate is present at about 0.05 weight/volume %, the one or more cetylpyridinum salts is present at about 0.1 weight/volume %, and the EDTA is present at about 0.1 weight/volume %.
32. A method of killing or inactivating microorganisms present on tissue of a patient, the method comprising: contacting the tissue of the patient with a composition according to claim 30.
Description:
TECHNICAL FIELD
[0001] This application relates to chlorhexidine antiseptics.
BACKGROUND
[0002] Chemicals and techniques for effectively killing pathogenic microorganisms are useful in the fields of human and veterinary medicine. Application of high heat and pressure in an autoclave is one technique to inactivate many pathogenic microorganisms. Various chemicals such as bleach, hydrogen peroxide, peracetic acid, and glutaraldehyde may be used to kill pathogenic microorganism. The difficulty of inactivating microorganisms varies with the organism. Disinfection is generally defined as including any process, chemical or physical, that destroys most pathogens but may not kill bacterial spores. Sterilization refers to methods and chemicals that destroy all viable forms of microbial life including bacterial spores. Both disinfection and sterilization generally refer to the destruction of microorganisms on non-living objects.
[0003] The difficult of inactivating microorganism can be ranked according to a scale of susceptibility. Generally, a chemical or process that kills microorganisms in a given susceptibility group will also kill microorganisms in easier-to-kill susceptibility groups. Table 1 below shows a scale of susceptibility with the more-difficult-to-kill microorganisms listed lower on the scale. Thus, if a disinfectant kills microorganisms in susceptibility group D such as M. tuberculosis that disinfectant will also kill microorganisms in susceptibility groups A-C.
TABLE-US-00001 TABLE I Scale of Susceptibility Microbial Susceptibility Group Microorganism (dried on carriers) A Retroviruses (AIDS), ortho and paramyxoviruses, herpes viruses, vaccinia, corona, and other enveloped viruses, gram negative rods and some filamentous fungi, some gram positive cocci, human hepatitis B virus B Staphylococcus aureus, some diphasic and filamentous fungi, yeasts and algae, some gram negative rods C Adenovirus D Mycobacterium tuberculosis (BCG strain), rotaviruses, reoviruses, some mold ascospores E Picornaviruses (polio, rhino), parvoviruses, hepatitis A F Bacterial endospore (Bacillus, Clostridinium), viroids G Prions (chronic infectious neuropathic agents, slow viruses)
[0004] Human skin is frequently colonized with a flora that varies depending on the location on the body and the setting. Normal human skin flora may include several types of bacteria such as gram-positive cocci, gram-positive-rods, and gram-negative bacteria. Most of these types of bacterial, other than gram-positive rods such as Bacillus and Clostridnium, are categorized in microbial susceptibility groups A and B above. Thus, any solution which kills microorganisms in groups B, or any of the more-difficult-to-kill groups, would be effective against most bacterial that normally colonizes human skin.
[0005] Skin and soft tissue infections are among the most common type of infections afflicting humans. Skin and soft tissue infections may lead to serious local and systemic complications. One of the common causes of skin and soft tissue infections is the occurrence of secondary bacterial infection that complicates treatment of skin lesions. Skin lesions that can also be secondarily infected with bacteria and fungi. Thus, a skin or soft tissue infection may actually be a result of the interaction of multiple microorganisms. Examples of this type of skin lesion include, but are not limited to, skin lesions caused by scabies, psoriasis, poison ivy, atopic dermatitis, eczema herpeticum, or kerion. Oral or systemic antibiotics may be effective at treating bacteria. However, there is a delay while a systemic antibiotic moves through a patient's body to the site of infection. Additionally, antibiotics are not effective for treating infections caused by microorganisms other than bacteria. Thus, there is a need for treatment techniques that can address infections caused by multiple microorganisms.
[0006] Many of the techniques and chemicals used for disinfection and sterilization are not suitable for application to living tissue or skin. The features of such techniques which make them effective at killing pathogenic microorganisms also cause harm or death to healthy living tissue. Antimicrobial substances that are suitable for application on the skin or tissue of humans and animals are referred to as antiseptics. However, because of the design for use on living tissue, many antiseptics are less effective at killing pathogenic microorganisms than disinfectants or sterilants. Thus, there is a need for antiseptics with improved efficacy.
SUMMARY
[0007] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0008] An embodiment of the invention concerns a composition including chlorohexidine, a surfactant, and a cationic quaternary ammonium compound. One embodiment of the invention concerns the composition described above wherein the surfactant comprises N-acyl sarcosinate. Another embodiment of the invention concerns the composition described above wherein the cationic quaternary ammonium compound comprises cetylperidium chloride (CPC). Yet another embodiment concerns chlorohexidine, a surfactant, a cationic quaternary ammonium compound, and a chelating agent. Still another embodiment concerns the chelating agent including ethylenediaminetetraacetic acid (EDTA).
[0009] The compositions described in the disclosure are suitable for use as antiseptics due to low toxicity yet strong enough to kill or inactivate pathogenic microorganisms.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIGS. 1-5 shows photographs of a lesion infected with MRSA healing in response to treatment with a chlorohexidine solution.
DETAILED DESCRIPTION
[0011] The present invention concerns compositions that are effective for killing microorganisms including, for example, difficult-to-kill microorganisms such as Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus while also being suitable for topical application as an antiseptic. Disinfectants or sterilants for hard surface or "cleaning" applications may be designed to be effective against such difficult-to-kill microorganisms without regard for harm or irritation that could be caused to living tissue. Antiseptics are often less effective for killing or inactivating microorganisms because antiseptics are generally designed to cause little or no irritation to healthy, living tissue. The compositions disclosed herein are suitable for use as antiseptics, yet due to the particular combination of components show surprisingly high efficacy against even difficult-to-kill microorganisms.
[0012] Unless otherwise indicated, all numbers expressing percentages of ingredients are to be understood as indicating approximate weight/volume percentages. Accordingly, unless explicitly indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Further, the ranges stated in this disclosure and the claims are intended to include the entire range including the endpoint(s).
[0013] According to an embodiment, the present invention concerns a composition that includes a mixture of chlorhexidine, a surfactant, and a cationic quaternary ammonium compound to form an antiseptic mixture that is more effective at inactivating pathogenic microorganisms than any of those chemicals alone. According to certain embodiments, chlorhexidine may be combined with gluconic acid to form chlorhexidine gluconate. Chlorhexidine, either as chlorhexidine gluconate, chlorhexidine hydrochloride, chlorhexidine dihydrochloride, chlorhexidine diacetate, or in another form, may be present at levels of about 0.4 to about 5 weight/volume %, or about from about 0.8 to about 1 weight/volume %, or even about 0.96 weight/volume %.
[0014] In another embodiment, the surfactant may be a nonionic surfactant or an ionic surfactant. Examples of nonionic surfactants include anhydrosorbitol esters and ethyloxated derivatives thereof. Examples of ionic surfactants include carboxylate surfactants, sulfate surfactants, and sarcosinate surfactants. According to certain embodiments, the surfactant may be present at levels of from about 0.01 to about 1 weight/volume %, from about 0.03 to about 0.1 weight/volume %, or even at about 0.05 weight/volume %. Some surfactants, for example sarcosinate surfactants, generally exhibit only minimal penetration into the stratum corneum membrane thereby maintaining membrane integrity. Sarcosinate surfactants may include, but are not limited to, sarcosine (N-methylglycine), sodium lauroyl sarcosinate, ammonium lauroyl sarcosinate, sodium cocoyl sarcosinate, sodium myristoyl sarcosinate, sodium oleoyl sarcosinate, or N-acyl sarcosinate (sarkosyl).
[0015] In an embodiment, the cationic quaternary ammonium compound may be, but is not limited to, benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetalkonium chloride, cetylpyridinium chloride (CPC), cetylpyridinium bromide, cetrimonium, cetrimide, dofanium chloride, tetraethylammonium bromide, or domiphen bromide. According to certain embodiments, the cationic quaternary ammonium compound may be present at levels of from about 0.01 to about 1 weight/volume %, from about 0.03 to about 0.1 weight/volume %, or even about 0.05 weight/volume %. According to certain embodiments, cationic quaternary ammonium compounds, such as CPC, are non-corrosive, effective over a wide pH range (pH 3 to 10.5), stable at high temperatures, relatively stable in the presence of organic matter, and exhibit low irritation and low toxicity.
[0016] According to one embodiment, the present invention concerns a composition that comprises a mixture of chlorhexidine, a surfactant, a cationic quaternary ammonium compound as presented above together with a chelating agent. The chelating agent may be, but is not limited to, ethylenediaminetetraacetic acid (EDTA); diethylenetriaminepentaacetic acid (DPTA); Aminotrimethylene phosphonic acid, Beta-Alanine Diacetic Acid, Calcium Disodium ethylenediaminetetraacetic acid (EDTA), Citric Acid, Cyclodextrin, Cyclohexanediamine Tetraacetic Acid, Diammonium Citrate, Diammonium EDTA, Diethylenetriamine Pentamethylene Phosphonic Acid, Dipotassium EDTA, Disodium Azacycloheptane Diphosphonate, Disodium EDTA, Disodium Pyrophosphate, EDTA, Etidronic Acid (HEDP, Hydroxyethylidene diphosphonic acid), Galactaric Acid, Gluconic Acid, Glucuronic Acid, HEDTA, Hydroxypropyl Cyclodextrin, Methyl Cyclodextrin, Pentapotassium Triphosphate, Methyl glycine diacetic acid (MGDA), Pentasodium Aminotrimethylene Phosphonate, Pentasodium Ethylenediamine Tetramethylene Phosphonate, Pentasodium Pentetate, Pentasodium Triphosphate, Pentetic Acid, Phytic Acid, Polyamine, Potassium Citrate, Potassium EDTMP, Potassium Gluconate, Potassium Polyphosphate, Potassium Trisphosphonomethylamine Oxide, Ribonic Acid, Sodium Chitosan Methylene Phosphonate, Sodium Citrate, Sodium Diethylenetriamine Pentamethylene Phosphonate, Sodium Dihydroxyethylglycinate, Sodium EDTMP, Sodium Gluceptate, Sodium Gluconate, Sodium Glycereth-1 Polyphosphate, Sodium Hexametaphosphate, Sodium Metaphosphate, Sodium Metasilicate, Sodium Phytate, Sodium Polydimethylglycinophenolsulfonate, Sodium Trimetaphosphate, TEA-EDTA, TEA-Polyphosphate, Tetrahydroxyethyl Ethylenediamine, Tetrahydroxypropyl Ethylenediamine, Tetrapotassium Etidronate, Tetrapotassium Pyrophosphate, Tetrasodium EDTA, Tetrasodium Etidronate, Tetrasodium Pyrophosphate, Tripotassium EDTA, Trisodium Dicarboxymethyl Alaninate, Trisodium EDTA, Trisodium HEDTA, Trisodium MGDA, Trisodium N, N-bis(carboxymethyl)glycine (NTA), or Trisodium Phosphate. The chelating agent may be included at levels of from about 0.05 to about 2 weight/volume %, or from about 0.08 to about 1 weight/volume %, or even about 0.1 weight/volume %.
[0017] A liquid solution containing 0.96% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, 0.1% CPC, and 0.1% EDTA may be used to kill or inactivate enveloped viruses, non-enveloped viruses, gram-positive bacteria, gram-negative bacteria, fungi, and other microorganisms. This liquid solution is also tuburculocidal; it can kill Mycobacterium tuberculosis. This level of efficacy corresponds to microbial susceptibility group A-D shown in Table 1. Surprisingly, the efficacy against mycobacteria, such as M. tuberculosis, is much greater than any of the components separately at the listed concentrations. The liquid solution may be made with an aqueous solvent such as water or a saline solution with a salinity and acidity appropriate for the intended application.
[0018] Many disinfectants or sterilants are effective at killing microorganisms on hard surfaces, but are too harsh for application to living tissue (e.g., bleach). However, the chlorhexidine solutions disclosed herein provide the additional surprising benefit of being non-irritating and suitable for application on sensitive tissue. Chlorhexidine gluconate is used, for example, in a 4% weight/volume solution as a surgical hand scrub without harm to skin. The concentrations of chlorohexidine discussed herein generally are at the same or lower levels then the level used for surgical hand scrubs. Sarcosinate surfactants exhibit only minimal penetration into the skin thereby reducing the potential for harm or irritation to skin or other tissue. Additionally, CPC exhibits low irritation and low toxicity.
[0019] Embodiments of the present invention may be formulated as, for example, aqueous mixtures, gels, creams, lotions, emulsions, or dry powders. Antiseptics based on any embodiment of the present invention may be used for applications including, but not limited to, pre-surgical skin scrubs, field antiseptics for trauma/military situations, veterinary treatment of mange or similar skin diseases, or an irrigant when performing root canal therapy. Due to the high level of efficacy in killing microorganisms this antiseptic mixture may, unlike other antiseptics, be used in applications where sexually transmitted diseases (STDs), MRSA (methicillin-resistant Staphylococcus aureus), and/or mycobacteria such as Mycobacterium tuberculosis are present.
[0020] The following examples are submitted for a better understanding of the invention.
EXAMPLES
Example 1
[0021] In this example, the test composition comprises 0.96% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, 0.1% EDTA, and 0.1% CPC. This example tests for tuberculocidal properties of the test solution. The microorganism used in the test was Mycobacterium bovis. M. bovis causes tuberculosis in cattle and is related to M. tuberculosis which causes tuberculosis in humans. Efficacy against M. bovis indicates efficacy against M. tuberculosis. Referring to the scale of susceptibility shown in Table 1, the efficacy against M. tuberculosis, which is in microbial susceptibility group D, also indicates efficacy against microorganisms in the easier-to-kill groups A-C.
[0022] A 0.1 mL aliquot of M. bovis culture inoculum was added to 10 mL of the test composition identified above. The test composition had a pH of about 5.5. Efficacy was tested after five minutes of exposure and after 10 minutes of exposure. A total of five replicates were used for each time period. A neutralizer was added to stop the activity of the test composition at the end of the time periods. None of the five replicates tested positive for presence of M. bovis after either five minutes or 10 minutes of exposure. Test results are provided below in Table 2.
TABLE-US-00002 TABLE II Number of positive tests out of 5 replicates Organism 5 minutes 10 minutes Mycobacterium bovis 0 0
[0023] The results of example 1 show efficacy of the test composition, which is suitable for topical use as an antiseptic, against M. tuberculosis.
Example 2
[0024] In this example, five different test compositions were prepared. Test composition 1 was 0.96% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, 0.1% EDTA, and 0.1% CPC. Test composition 2 was 0.05% N-acyl sarcosinate, 0.1% EDTA, and 0.1% CPC. Test composition 3 was 0.96% chlorhexidine gluconate, 0.1% EDTA, and 0.1% CPC. Test composition 5 was 0.96% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, and 0.1% CPC.
[0025] The microorganism used in the test was Mycobacterium smegmatis. M. smegmatis is a non-pathogenic bacteria related to M. tuberculosis which causes tuberculosis in humans. Efficacy against M. smegmatis indicates efficacy against M. tuberculosis.
[0026] Example 2 includes in-vitro time-kill tests performed for each of the five test composition listed in the preceding paragraph against M. smegmatis. M. smegmatis suspension with an inoculum level of 9.150×106 colony-forming unit (CFU)/ML was used for all tests. A 0.1 mL aliquot of the M. smegmatis suspension was added to 9.9 mL of the respective test compositions and exposed for periods of one minute, five minutes, and 10 minutes. At the end of each exposure period, a neutralizer was added to stop bactericidal activity of the test compositions.
[0027] Test composition 1 was effective in reducing the number of CFU/mL at each exposure length and achieved a greater than 2.5 Log10 reduction after 10 minutes of exposure. Test results are provided below in Table 3.
TABLE-US-00003 TABLE III Post-exposure population change (test composition 1) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Mycobacterium 1 1.8050 × 106 0.7049 80.2732 smegmatis 5 5.40 × 104 2.2290 99.4098 10 1.020 × 104 2.9528 99.8885
[0028] This shows that test composition 1 is effective against M. tuberculosis. This supports the results of example 1.
[0029] Test composition 2, without chlorhexidine gluconate, did not kill M. smegmatis after one or five minutes of exposure. Test results are provided below in Table 4. The test substance was not fully inactivated during the test with 10 minutes of exposure. Thus, the detected efficacy may be higher than it would have been if the bactericidal properties of the test substance were fully inactivated when the neutralizer was added. True efficacy is likely lower than the efficacy shown in Table 4.
TABLE-US-00004 TABLE IV Post-exposure population change (test composition 2) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Mycobacterium 1 1.0750 × 107 0.0000 0.0000 smegmatis 5 1.0950 × 107 0.0000 0.0000 *10 7.1 × 106 0.1101 22.4044 *Test substance not fully inactivated by neutralizer
[0030] This shows that a composition without chlorhexidine has reduced antiseptic properties.
[0031] Test composition 3, without a surfactant (e.g., N-acyl sarcosinate) had similar efficacy to that of test composition 1. However, test composition 3 was not fully inactivated for any of the tests. Thus, efficacy results would likely be lower if there was full neutralization. Test results are provided below in Table 5.
TABLE-US-00005 TABLE V Post-exposure population change (test composition 3) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Mycobacterium *1 1.950 × 106 0.6714 78.6885 smegmatis *5 3.850 × 104 2.3759 99.5792 *10 6.950 × 103 3.1194 99.9240 *Test substance not fully inactivated by neutralizer
[0032] Although this test appears to show minimal effect on efficacy when a surfactant is omitted from the composition, results when there is effective neutralization would likely show a larger decrease in antiseptic properties. Thus, this suggests that addition of a surfactant increases efficacy.
[0033] Test composition 4, without a cationic quaternary ammonium compound (e.g., CPC) showed decreased efficacy against M. smegmatis. However, test composition 4 was not fully inactivated at any of the time points. Thus, efficacy results would likely be even lower if there was full neutralization. Test results are provided below in Table 6.
TABLE-US-00006 TABLE VI Post-exposure population change (test composition 4) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Mycobacterium *1 4.350 × 106 0.3229 52.4590 smegmatis *5 6.250 × 105 1.1655 93.1694 10 2950 × 105 1.4616 96.7760 *Test substance not fully inactivated by neutralizer
[0034] This shows that inclusion of a cationic quaternary ammonium compound increases efficacy.
[0035] Test composition 5, without a chelating agent (e.g., EDTA), showed decreased efficacy against M. smegmatis but still achieved a greater than 2.5 Log10 reduction after 10 minutes of exposure. Test results are provided below in Table 7.
TABLE-US-00007 TABLE VII Post-exposure population change (test composition 5) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Mycobacterium 1 2.3550 × 106 0.5894 74.2623 smegmatis 5 1.2150 × 105 1.8768 98.6721 10 2.3250 × 104 2.5950 99.7459
[0036] This shows that a chelating agent may be omitted without significant decreases in the ability to kill or inactivate microorganisms in at least some situations.
[0037] The tests in example 2, taken together, show that each of the separate compounds included in test composition 1, with the possible exception of the chelating agent, contributes the efficacy as an antiseptic against bacteria that cause tuberculosis. This combinatorial effect was both surprising and unexpected.
Example 3
[0038] In this example, the test composition comprises 0.96% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, 0.1% EDTA, and 0.1% CPC. This example compares the test composition to a solution of 4% chlorhexidine gluconate. The microorganism used in the test was methicillin-resistant Staphylococcus aureus. Methicillin-resistant Staphylococcus aureus (MRSA) is a strain of S. aureus that is resistant to beta-lactam antibiotics.
[0039] An in-vitro time-kill test was performed on S. aureus using both the test composition and the solution of 4% chlorhexidine gluconate. A S. aureus suspension with an inoculum level of 1.460×107 colony-forming units (CFU)/ML was used for all tests. A 0.1 mL aliquot of the S. aureus suspension was added to 9.9 mL of the test composition or the 4% chlorhexidine gluconate solution and exposed for periods of one minute, five minutes, and 10 minutes. At the end of each exposure period, a neutralizer was added to stop the bactericidal activity. Test results are provided below in Tables 8 and 9.
TABLE-US-00008 TABLE VIII Post-exposure population change (test composition) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Staphylococcus 1 2.350 × 101 4.7933 99.9984 aureus 5 <1.00 × 101 6.1644 99.9999 10 <1.00 × 101 6.1644 99.9999
TABLE-US-00009 TABLE IX Post-exposure population change (4% chlorhexidine gluconate) Exposure Post-exposure Time population Log10 Percent Organism (minutes) (CFU/ML) reduction reduction Staphylococcus 1 1.2150 × 103 4.0798 99.9917 aureus 5 <1.00 × 101 6.1644 99.9999 10 <1.00 × 101 6.1644 99.9999
[0040] The results of example 3 show that the test composition achieves results similar to 4% chlorhexidine gluconate solution with only one-quarter as much chlorhexidine gluconate. Chlorhexidine may be irritating to sensitive tissue at high concentrations, so achieving similar efficacy with a lower concentration is a benefit.
Example 4
[0041] This example shows the efficacy of a chlorhexidine solution including 0.48% chlorhexidine gluconate, 0.05% N-acyl sarcosinate, 0.1% EDTA, and 0.1% CPC for treating a lesion infected with MRSA. Example 4 also shows a lack of irritation to the surrounding tissue over a month-long course of application. The treatment process included (1) spraying or apply the chlorohexidine solution on the infected site and leaving wet for one minute, (2) after one minute placing a gauze pad thoroughly saturated with the chlorohexidine solution over the lesion and affixing in place with tape, (3) repeating steps (1) and (2) at least twice daily to remove the purulent matter exuding from the lesion; (4) covering the lesion at night to maintain sterility, and (5) repeating steps (1)-(4) until the exudate from lesion ceases.
[0042] FIGS. 1-5 show the healing of a MRSA infected lesion on a human knee in response to application of the chlorohexidine solution. FIG. 1 shows a picture 100 of the knee with the lesion 102 prior to treatment. The patient reported a feeling of immediate relief upon application of the chlorohexidine solution and did not report any irritation or discomfort due to the chlorohexidine solution. FIG. 2 shows a picture 200 of the knee and a slightly smaller lesion 202 after 5-8 days of treatment. FIG. 3 shows a picture 300 of the knee with the lesion 303 exhibiting significantly less purulent matter following an additional 5-8 days of treatment. FIG. 4 shows a picture 400 of the knee with the lesion 402 reduced in size following additional 5-8 days of treatment. FIG. 5 shows a photograph 500 of the knee following healing of the lesion 502. The photograph 500 in FIG. 5 was taken 5-8 days after the photograph 400 of FIG. 4. The total time from the start of treatment until the condition shown in the final photograph 500 was about one month. Moreover, after approximately 60 applications (i.e., twice daily for a month) including prolonged contact with saturated gauze pads, the epidermis of the knee shows no signs of irritation.
[0043] Although the subject matter of this disclosure has been described in language specific to chemical composition and/or methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the chemical compositions or methods described above. Rather, the specific chemical compositions and methods are disclosed as illustrative techniques for implementing the claims.
User Contributions:
Comment about this patent or add new information about this topic: