WO2005016386A1

WO2005016386A1 - Improved therapeutic protocols

Info

Publication number: WO2005016386A1
Application number: PCT/AU2004/001108
Authority: WO
Inventors: Tracey Brown; Gary Brownlee; Richard Fox
Original assignee: Meditech Research Limited
Priority date: 2003-08-19
Filing date: 2004-08-19
Publication date: 2005-02-24

Abstract

The present invention relates generally to therapeutic protocols to ameliorate infection by pathogenic agents. More particularly, the present invention relates to the use of hyaluronan (HA) or any of its chemical derivatives in conjunction with an anti-pathogenic agent to reduce its toxic effects and/or to target the anti-pathogenic agent to an infected cell which expresses HA-binding proteins including HA receptors. Even more particularly, HA is administered in conjunction with an anti-pathogenic agent to facilitate the prolonged administration of the agent, while reducing its toxic side affects and/or to facilitate targeted delivery of the anti-pathogenic agent. Owing to the protective effects of HA, the dose of anti-pathogenic agent may be substantially higher than a generally accepted effective dose, which would other wise cause unacceptable side effects in the subject.

Description

IMPROVED THERAPEUTIC PROTOCOLS

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The present invention relates generally to therapeutic protocols to ameliorate infection by pathogenic agents. More particularly, the present invention relates to the use of unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives in conjunction with an anti-pathogenic agent to reduce its toxic effects and/or to target the anti-pathogenic agent to an infected cell which expresses HA-binding proteins including HA receptors. Even more particularly, HA is administered in conjunction with an anti- pathogenic agent to facilitate the prolonged administration of the agent, while reducing its toxic side affects and/or to facilitate targeted delivery of the anti-pathogenic agent. Owing to the protective effects of HA, the dose of anti-pathogenic agent may be substantially higher than a generally accepted effective dose, which would other wise cause unacceptable side effects in the subject.

DESCRIPTION OF THE PRIOR ART

Bibliographic details of the references provided in the subject specification are listed at the end of the specification.

Reference to any prior art in this specification is not, and should not be taken as an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in any country.

Systemic fungal infections are a major cause of mortality in cancer patients receiving chemotherapy and in other immunosuppressed individuals, such as transplant recipients receiving immunosuppressive therapies and HIV infected individuals. Fungal infections, one of the major categories of opportunistic infections, are a continued and growing concern for the management of immunocompromised patients. Unfortunately, fungal infections very often defy treatment because the few drugs which destroy fungi are extremely toxic to the host. Because of the drugs' toxicity, the lowest possible effective doses should be given. However, as the drugs are diluted in the blood and large amounts of the drugs are degraded, or excreted or taken up by uninfected tissue, large doses actually are required to be given if the treatment is to be effective. Current protocols involving the use of anti-fungal agents can be improved in the areas of toxicity, routes of administration, and quality of life for the patient.

The preferred treatment for systemic fungal infections is primarily limited to two groups of drugs: the polyene antibiotics such as Amphotericin B and nystatin, and the imidazoles, such as ketaconazole and miconazole. Amphotericin B is active against most pathogenic fungi, yeast, and some types of protozoa, and is considered the "gold-standard" for the treatment of severe, systemic fungal infections. It acts by binding to ergosterol, a sterol found in the cell membrane of fungi. Binding of Amphotericin B forms pores in the fungal membrane that leads to leakage of intracellular ions and cell death.

Ergosterol is unique to fungal membranes, but is similar in structure to cholesterol found in human cell membranes hence Amphotericin B can bind to human cholesterol and damage cells. Amphotericin B has thus been associated with acute hemolytic crisis. Further, because it is particularly toxic to kidney tissue, it has been associated with irreversible renal damage and even kidney failure, at therapeutic dosage levels (Medoff and Kabayashi, New England Journal of Medicine 302: 145-55, 1980; Cohen, Lancet ii: 532-37, 1982; Graybill and Craven, Drugs 25: 41-62, 1983. Treatment with this drug is notorious for causing nephrotoxicity, with estimates showing that around 50% of people treated with the drug show renal damage. There is a need, therefore, to enable the administration of dosages of anti-pathogenic agents high enough to control infection on the one hand, and unacceptable damage to healthy tissues on the other.

SUMMARY OF THE INVENTION

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations thereof such as "comprises" and "comprising", will be understood to imply the inclusion of stated integer or step or group of integers or steps but no to the exclusion of any other integer or step of integers or steps.

The present invention contemplates a method for treating infection by a pathogen or otherwise ameliorating the effects of infection by administering to a subject a therapeutically effective amount of a composition comprising an anti-pathogenic agent and unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives . In a related aspect, the present invention contemplates the treating a pathogenic infection caused by a fungi, bacterium or a virus, comprising administering to a subject a therapeutically effective amount of an anti-pathogenic agent and unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives .. In a preferred aspect, the present invention provides a method of treating a pathogenic infection in a subject comprising administering to a subject amphotericin B and unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives . Due to the protective effects of HA, the present invention allows for higher and prolonged doses of the anti-pathogenic agents contemplated by the present invention. In addition or alternatively, the present invention enables selected targeting of anti-pathogenic agents to cells expressing HA- binding proteins so enabling the administration of lower doses of therapeutic agent due to the transport/targeting capabilities of the HA. Such proteins include HA receptors. The HA may be administered in a composition with the agent or prior to or post administration of the agent. Accordingly, simultaneous or sequential of HA and the agent, in either order, is proposed.

In another aspect, the methods of the present invention are contemplated for use in an immunocompetent subject infected by a pathogen. In a preferred aspect, the method of the present invention is used for treating a pathogenic infection in an immunocompromised subject. The present invention further contemplates the treatment of pathogenic infections, or non- symptomatic colonization, of a host by any microorganism or virus. This is to be understood to specifically include, but not be limited to viruses, bacteria, fungi (including yeasts), ectoparasites, mycoplasms, Archea, algae, oomycetes, slime molds, nematodes and amoebeae.

In a particularly preferred embodiment, the present invention provides methods comprising the use of HA in conjunction with an anti-fungal compound, such as Amphotericin B or its functional equivalents, for the treatment of fungal infections in immunocompetent or immunocompromised subjects. The disclosed method leads to treatment of the fungal infection with reduced side-effects (such as renal toxicity) when compared to antifungal treatment alone. The subject method further enables targeted therapy by directing the antifungal agent to a cell expressing HA-binding proteins.

Specifically, the present invention identifies that unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives .preadministered, postadministered or coadministered with Amphotericin B, can mitigate, inter alia, the renal toxicity of the Amphotericin B, without reducing the antifungal potency. Such mitigation is also referred to herein as amelioration.

Although specifically exemplified with regard to the in vivo treatment of pathogenic infections, the present invention also contemplates the use of unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives, in conjunction with an antimicrobial agent in an in vitro cell culture.

The present invention also provides pharmaceutical compositions comprising unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives . and an antimicrobial agent together with one or more pharmaceutically acceptable carriers or diluents. Alternatively, a pharmaceutical pack is provided with unmodified hyaluronan (HA) or any of its chemically stabilized or modified derivatives and the agent maintained separately with instructions to mix before administration or to administered one or the other first followed by the other one.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a graphical representation showing the effect on serum creatinine levels in rats chronically exposed to Amphotericin B either in the presence or absence of HA. Rats were pre-bled (day 0: baseline creatinine) then injected for 5 days with drug combinations of amphotericin B at a dosage of 0.75mg/kg per day. Mean change of serum creatinine as a percentage of day 0 ± SEM was then plotted. Fungizone ( ), HyAMP [Trademark]

( ) and HA 15 minutes before fungizone ( ). An increase of 25% in serum creatinine is considered as a sign of kidney damage and it is recommended that amphotericin B treatment be discontinued.

Figure 2 is a graphical representation of the tissue burden of mice challenged with Candida albicans after antifungal therapy with amphotericin B in the presence and absence of HA. Female immunocompetent Balb/c mice (18-22g) were challenged intravenously with 2.5 x 10⁶ viable C.albicans. At day 3 and 10 after challenge mice received anti-fungal therapy of either HyAMP [Trademark] (HA:824kDa, l.Omg/kg amphotericin B) or HyAMP [Trademark] (HA: 1.6 x 10⁶, l .Omg/kg amphotericin B). Mice receiving lectade supplementation are indicated. Data represents the average colony forming units expressed as logio ± SD (where n==8). To ensure homogeneity of Candida sp from infected kidneys colonies were sub-cultured onto ChromAgar plates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is predicated in part on the determination that HA may be used as a protective agent in, subjects receiving treatment with an anti-pathogenic agent. Although pathogenic infections may occur in an immunocompetent host, they are more common in subjects who are immunocompromised. Anti-pathogenic agents, when used in both the immunocompetent and immunocompromised host typically result in toxicity in the recipient. The most commonly observed side effects include fever, chills and myalgia. Nephrotoxicity is the major adverse effect limiting the use of these compounds. The manifestations of nephrotoxicity are azotemia, decreased glomerular filtration, loss of urinary concentrating ability, renal loss of sodium and potassium, and renal tubular acidosis. The renal injury reduces erythropoietin production and leads to a normochromic normocytic anemia. Therefore, the present invention relates to the discovery that toxicity observed when treating a subject with an anti-pathogenic agent is reduced when the anti- pathogenic agent is pre-, post- or co-administered with HA. In addition, pre-, post- or co- treatment with HA and an anti-pathogenic agent enables selective targeting of the anti- pathogenic agent to cells expressing HA-binding proteins. The HA of the present invention may be modified or non-modified. Modified HA includes derivatized HA, (i.e. chemically cross-linked HA), HA chemically conjugated to the anti -pathogenic agent drug and/or stabilized HA.

It is to be understood, that unless otherwise indicated, the subject invention is not limited to specific formulations or components, manufacturing methods, dosage regimens or the like, and as such may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The HA may be administered simultaneously or sequentially in respect to the agent. Sequential administration includes administering one of HA and the agent followed by the other of HA and the agent within nanoseconds, seconds, minutes, hours or days of each other.

It must also be noted, as used in the subject specification, the singular forms "a", "an" and "the" include plural aspects unless the context clearly dictates otherwise. Thus, for example, reference to an "anti-pathogenic agent" includes a single anti-pathogenic agent, as well as two or more anti -pathogenic agents; and reference to a pathogen includes reference to a single pathogen as well as two or more pathogens.

Accordingly, the present invention contemplates a method of treating a subject infected with a pathogenic agent, said method comprising administering to said subject a therapeutically effective amount of a composition comprising an anti-pathogenic agents and HA.

"Subject" as used herein refers to an animal, preferably a mammal and more preferably human who can benefit from the method of the present invention. There is no limitation, however, on the type of animal that could benefit from the present method. A subject regardless of whether a human or non-human animal may be referred to as an individual, subject, patient, animal, host or recipient. The method of the present invention has applications in human medicine, veterinary medicine as well as in general, domestic or wild animal husbandry. Preferably, the candidate subject is a mammal such as a human or laboratory test animal such as a mouse, rat, rabbit, guinea pig, hamster, zebrafish or amphibian or avian species such as a duck.

The HA is also useful to target an anti-pathogenic agent to cells expressing HA-binding proteins.

Further, it should be appreciated that the use of anti-pathogenic agents in conjunction with HA may also be useful in in vitro culture systems to allow for the irradication and/or killing of a pathogen within a culture, whilst resulting in minimal adverse side-effects to the cells maintained in the culture system. The anti-pathogenic agent in conjunction with HA also has application as a selection agent in in vitro culture systems, and as such may be incorporated into or subsequently applied to culture media. As used herein, the anti-pathogen compositions of the present invention include any compositions which inactivate, kill, retard the growth of or otherwise inhibit pathogen growth, viability, or maintenance. Preferably, the anti-pathogen compositions of the present invention comprise an anti-pathogenic agent and HA, wherein the composition acts by inactivating, killing, retarding the growth or otherwise inhibiting the pathogen. The HA may optionally target the anti-pathogenic agent to cells expressing HA receptors or HA- binding proteins. The compositions of the present invention further act by ameliorating the symptoms of a disease or disorder caused or exacerbated by a pathogen. In addition, the compositions of the present invention further act by reducing or abolishing the side-effects caused when the anti-pathogenic agents is administered in the absence of HA.

Being a polymeric molecule, HA molecules exhibit a range of varying molecular weights. HA formulations may, therefore, comprise molecules of different molecular weights or may be fractionated to a substantially homogenous weight. Almost any average of modal molecular weight formulation of HA may be effective ranging from 390Da to 5,000kDa in the methods of the present invention. Preferred formulations, however, exhibit higher rather than lower modal molecular weights. Molecular weight ranges of HA contemplated herein preferentially include from about 50,000 to about 20,000,000 Da. HA having a modal molecular weight in the range 750,000 to 2,000,000 Da is however, particularly preferred. Higher molecular weight HA has the advantage of forming a tertiary structure whereby at low concentrations, it self-aggregates forming a three-dimensional meshwork, which exhibits the characteristics of controllable porosity and molecular dimension, which enables the establishment of equilibrium between therapeutic molecules held within the volumetric domain of the polysaccharide and the external environment. The "loading" of the HA three-dimensional structure with therapeutic molecules results in a controlled release of the therapeutic agent at the pathological site, subsequently overcoming nonspecific targeting of healthy tissue. A particularly preferred weight range is 750,000- 2,000,000 Da. Examples of particularly useful molecular weight of HA include 750,000; 751,000; 752,000; 753,000; 754,000; 755,000; 756,000; 757,000; 758,000; 759,000 760,000; 761,000; 762,000; 763,000; 764,000; 765,000; 766,000; 767,000; 768,000 769,000; 770,000; 771,000; 772,000; 773,000; 774,000; 775,000; 776,000; 777,000

,051,000 052,000 1,053,000 ,059,000 060,000 1,061,000 ,067,000 068,000 1,069,000 ,075,000 076,000 1,077,000 ,083,000 084,000_: 1,085,000 ,091,000 092,000 093,000 ,099,000 100,000 101,000 ,107,000 108,000 109,000 ,115,000 116,000 117,000 ,123,000 124,000 125,000 ,131,000 132,000 133,000 ,139,000 140,000 141,000 ,147,000 148,000 149,000 ,155,000 156,000 157,000 ,163,000 164,000 165,000 ,171,000 172,000 173,000 ,179,000 180,000 181,000 ,187,000 188,000 189,000 ,195,000 196,000 197,000 ,203,000 204,000 205,000 ,211,000 212,000 213,000 ,219,000 220,000 221,000 ,227,000 228,000 229,000 ,235,000 236,000 237,000 ,243,000 244,000 245,000 ,251,000 252,000 253,000 ,259,000 260,000 261,000 ,267,000 268,000 269,000 ,275,000 276,000 277,000 ,283,000 284,000 285,000 ,291,000 292,000 293,000

,299,000 1,300,000 1,301,000 1,305,000 1,306,000,307,000 1,308,000 1,309,000 1,313,000 1,314,000,315,000 1,316,000 1,317,000 1,321,000 1,322,000,323,000 1,324,000 1,325,000 1,329,000 1,330,000,331,000 1,332,000 1,333,000 1,337,000 1,338,000,339,000 1,340,000 1,341,000 1,345,000 1,346,000,347,000 1,348,000 1,349,000 1,353,000 1,354,000,355,000 1,356,000 1,357,000 1,361,000 1,362,000,363,000 1,364,000 1,365,000 1,369,000 1,370,000_:,371,000 1,372,000 1,373,000 1,377,000 1,378,000,379,000 1,380,000 1,381,000 1,385,000 1,386,000,387,000 1,388,000 1,389,000 1,393,000 1,394,000,395,000 1,396,000 1,397,000 1,401,000 1,402,000,403,000 1,404,000 1,405,000 1,409,000 1,410,000,411,000. 1,412,000 1,413,000 1,417,000 1,418,000,419,000 1,420,000 1,421,000 1,425,000 1,426,000,427,000 1,428,000 1,429,000 1,433,000 1,434,000,435,000 1,436,000 1,437,000 1,441,000 1,442,000,443,000 1,444,000 1,445,000 1,449,000 1,450,000,451,000 1,452,000 1,453,000 1,457,000 1,458,000,459,000 1,460,000_: 1,461,000 1,465,000 1,466,000,467,000_; 1,468,000 1,469,000 1,473,000_: 1 ,474,000,475,000 1,476,000 1,477,000 1,481,000 1,482,000,483,000 1,484,000 1,485,000 1,489,000 1,490,000,491,000 1,492,000 1,493,000 1,497,000 1,498,000,499,000 1,500,000 1,501,000 1,505,000 1,506,000,507,000 1,508,000 1,509,000 1,513,000 1,514,000,515,000 1,516,000 1,517,000 1,521,000 1,522,000,523,000 1,524,000_: 1,525,000 1,529,000 1,530,000:,531,000 1,532,000 1,533,000 1,537,000 1,538,000,539,000 1,540,000 1,541,000

1,545,000 1,546,000 1,547,000 1,552,000 1,553,000 1,554,000 1,555,000 1,560,000 1,561,000 1,562,000 1,563,000 1,568,000 1,569,000 1,570,000 1,571,000 1,576,000 1,577,000 1,578,000 1,579,000 1,584,000 1,585,000 1,586,000 1,587,000 1,592,000 1,593,000 1,594,000 1,595,000 1,600,000 1,601,000 1,602,000 1,603,000 1,608,000 1,609,000 1,610,000 ^'1,611,000 1,616,000 1,617,000 1,618,000 1,619,000 1,624,000 1,625,000 1,626,000 1,627,000 1,632,000 1,633,000 1,634,000 1,635,000 1,640,000 1,641,000 1,642,000 1,643,000 1,648,000 1,649,000 1,650,000 1,651,000 1,656,000 1,657,000 1,658,000 1,659,000 1,664,000 1,665,000 1,666,000 1,667,000 1,672,000 1,673,000 1,674,000 1,675,000 1,680,000 1,681,000 1,682,000 1,683,000 1,688,000 1,689,000 1,690,000 1,691,000 1,696,000 1,697,000 1,698,000 1,699,000 1,704,000 1,705,000 1,706,000 1,707,000 1,712,000 1,713,000: 1,714,000 1,715,000 1,720,000 1,721,000 1,722,000_: 1,723,000 1,728,000 1,729,000 1,730,000 1,731,000 1,736,000 1,737,000 1,738,000 1,739,000 1,744,000 1,745,000 1,746,000 1,747,000 1,752,000 1,753,000 1,754,000 1,755,000 1,760,000 1,761,000 1,762,000 1,763,000 1,768,000 1,769,000 1,770,000 1,771,000 1,776,000 1,777,000 1,778,000 1,779,000 1,784,000 1,785,000 1,786,000 1,787,000

1,792,000 1,793,000 1,794,000 1,797,000 1,798,00 1,805,000 1,806,00 1,813,000 1,814,00 1,821,000 1,822,00 1,829,000 1,830,00 1,837,000 1,838,00 1,845,000 1,846,00 1,853,000 1,854,00 1,861,000 1,862,00 1,869,000 1,870,00 1,877,000 1,878,00 1,885,000 1,886,00 1,893,000 1,894,00 1,901,000 1,902,00 1,909,000 1,910,00 1,917,000: 1,918,00 1,925,000 1,926,00 1,933,000 1,934,00 1,941,000_; 1,942,00 1,949,000 1,950,00 1,957,000_; 1,958,00 1,965,000_: 1,966,00 1,973,000 1,974,00 1,981,000 1,982,00 1,989,000 1,990,00

1,997,000; 1,998,000; 1,999,000 and 2,000,000.

It should be noted that in certain circumstances, HA may be used at a molecular weight of <750,000 Da, >749,000 Da but less than 1,000,000 Da or >1, 000,000 Da. In addition to the anti-pathogenic compositions of the present invention containing HA, the compositions may also contain additional anti-pathogenic agents or therapeutic compounds. The anti -pathogenic agents or therapeutic compounds contemplated by the present invention include those which aid in the inactivation of a pathogen, such as anti- fungal agents, anti-viral agents and anti-bacterial agents. These agents may be targeted to cells bearing HA receptors or HA-binding proteins. Specifically this includes agents that are both inhibitory and/or toxic to the pathogen. For example in the case of anti-fungal agents, this includes both fungistatic and fungicidal compounds.

The anti -pathogenic compositions of the present invention may include one or more of the following anti-fungal agents: Clotrimazole, Fluconazole, Flucytosine, Itraconazole, etoconazole and Nystatin. In a preferred aspect, the anti-pathogenic compositions comprise Amphotericin B or a functional homolog or equivalent thereof and HA.

The anti-pathogenic compositions of the present invention may also include one or more of the following anti -viral agents: 3TC, Abacavir, Acyclovir, Alpha interferon, AZT, Bleomycin, Capreomycin, Cidofovir, Ciprofloxacin, Cyclophophamide, ddX, ddl, Delavirdine, Didanosine, Dronabinol, Efavirenz, Erythropoetin, Famciclovir, Filgrastim, Foscarnet, Ganciclovir, Ganciclovir implants, Indinavir, Lamivudine, Lopinavir, Megace, Methotrexate, Nelfinavir, Neviapine, Nonoxyl-9, Ribavirin, Ritόnavir, Saquinaver, Sulfamefhoxazole, Tenofovir, Trimethoprim, Zalcitabine and Zidovudine.

The anti-pathoegenic compositions of the present invention may also include one or more antibacterial agents of the following broad classes: macrolides, β-lactams, penecillins, sulfonamides, cephalosporins, fluoroquinolones, aminoglycosides and tetracyclines. Specific anti-bacterial agents may include: Amikacin, Atovaquone, Azithromycin, Clarithromycin, Clindamycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, IVIG, Kanamycin, Metronidazole, Ofloxacin, Para A inosalicyclic Acid, Pentamidine, Primaquine, Pyrazinamide, Pyrimethamine, Rifabutin, Rifampin, Streptomycin, Sulfadiazine, Sulfadoxine, Sulfamethazine, Trimetrexate, Triple Sulfa. According to the method of the present invention, HA can be used to avoid the need for undesirable reductions in the dose or duration of administration of a anti-pathogenic agent, in a subject. Unacceptably severe side effects including neutropenia, cardiac toxicity and gastro-intestinal toxicity as manifested by nausea, vomiting and severe weight loss, are mitigated against or avoided. That is, by pre- and/or co-administering an effective amount of HA, the dose of a anti-pathogenic agent may be increased to a level above that which would be possible if the anti-pathogenic agent were administered in the absence of the effective amount of HA.

Accordingly, the present invention contemplates a method which facilitates the prolonged administration of a dose of anti-pathogenic agent to a subject, wherein said dose may be up to a single dose may be up to 200% higher and/or the cumulative dose may be up to 600% higher than a generally accepted effective dose, said method comprising the pre- and/or co- administration of an effective amount of HA.

By "pre- or co-administering", it is to be understood that the HA may be administered before, at the same time as, or after the subject has been administered the anti-pathogenic agent. Where the HA is administered before the anti-pathogenic agent, preferably it is administered from about 24 hours to about 5 minutes, more preferably from about 12 hours to about 10 minutes, still more preferably from about 5 hours to about 10 minutes, and most preferably about 0.5 hour, before administration of the anti-pathogenic agent. Where the HA is administered after the anti-pathogenic agent, preferably it is administered 0.05 to 24 hr, more preferably 0.1 to 5 hr, and most preferably about 0.5 hr, after administration of the anti-pathogenic agent.

The term "pathogen" refers to an organism or agent such as viruses, bacteria, fungi, yeasts, ectoparasites, mycoplasms, Archea, algae, oomycetes, slime molds, nematodes and amoebeae. Pathogens having a diameter of less than 0.1 μm are also included in this definition. Pathogens which cause disease are generally defined as agents having a diameter of 1 mm or less. Pathogens of the present invention refer to agents that cause disease or which have the potential to cause disease. Typically, pathogens may be divided into four distinct types: protozoa, bacteria, viruses, and fungi (including molds and yeasts), however, for the purposes of the present invention, a pathogen is any disease causing microorganism. Pathogens of the present invention may also infect or colonize the host, without the presence of disease.

The terms "effective amount" and "therapeutically effective amount" of an agent as used herein mean a sufficient amount of the agent to provide the desired therapeutic or physiological effect. Furthermore, an "therapeutically effective amount of a composition comprising an anti-pathogenic agent and HA" is an amount of anti-pathogenic agent which kills and/or inactivates a pathogen, while minimizing the side effects associated with the administration of the anti-pathogenic agent. Undesirable effects, e.g. side effects, are sometimes manifested along with the desired therapeutic effect, mean a practitioner must balance the potential benefits against the potential risks in determining what is an appropriate "effective amount". The exact amount required will vary from subject to subject, depending on the species, age and general condition of the subject, mode of administration and the like. Thus, it may not be possible to specify an exact "effective amount". However, an appropriate "effective amount" in any individual case may be determined by one of ordinary skill in the art using only routine experimentation.

The terms "treating" and "treatment" as used herein refer to reduction in severity and/or frequency of symptoms of diseases or disorders associated with pathogenic infections. Or a reduction in the severity and/or symptoms of disease associated with infectious agents that are inactivated and/or killed by anti -pathogenic agents. The use of the anti -pathogenic agent, in conjunction with HA should result in the elimination of symptoms and/or underlying cause, prevention of the occurrence of symptoms of disease and/or their underlying cause and improvement or remediation of damage, with minimal toxic side- effects.

"Treating" a patient may involve prevention of the disorder or disease condition or adverse physiological event in a susceptible individual as well as treatment of a clinically symptomatic individual by inhibiting a disease or disorder. The term "ameliorating" infection or the effects of infection include preventing infection or reducing the extent of infection or overcoming the effects of infection by a pathogenic agent.

As defined herein "toxicity" refers to a harmful effect (like that of a poison) that some substances or some medications have on the body. The effect can be minor or major and may only be found with special tests (a person may not know it is even happening). The harmful effect can last a very short time, a few weeks to months or sometimes be permanent. Examples of toxic effects caused by anti-pathogenic agents include, without being limited to, fever, chills, and myalgia. In addition to nephrotoxicity the manifestations of nephrotoxicity are azotemia, decreased glomerular filtration, loss of urinary concentrating ability, renal loss of sodium and potassium, and renal tubular acidosis. The renal injury reduces erythropoietin production and leads to a normochromic normocytic anemia.

In yet another embodiment, the present invention is directed towards methods of treating a pathogenic infection in an immunocompromised or immunosupressed subject comprising administering to the subject an anti-pathogenic agent and HA.

Immunosuppression is a disorder or condition where the immune response is reduced or absent. The immune system protects the body from potentially harmful substances (antigens) such as microorganisms, toxins, cancer cells, and blood or tissues from another person. The immune response consists of general actions such as phagocytosis, where white blood cells engulf and destroy "foreign" material. It protects against specific antigens by producing antibodies (immunoglobulins), which are molecules that attach to a specific antigen and make destruction of the antigen more efficient. It also protects against specific antigens by producing lymphocytes (a group of white blood cells) that become specialized (sensitized). The sensitized lymphocytes "recognize" the foreign substance, and they destroy it. Immunity is, in part, a product of lymphoid tissue in the body that includes the thymus, lymph nodes, tonsils, parts of the spleen and gastrointestinal tract, and bone marrow. Lymphocytes (the specialized white blood cells that provide acquired immunity) are produced or mature in various lymphoid tissues. Lymphocytes are divided into two groups. T lymphocytes become the sensitized lymphocytes that directly attack (cellular immunity). B lymphocytes produce antibodies (humoral immunity) that attach to the antigen and make phagocytes and body chemicals such as complement proteins much more efficient in the destruction of the antigen.

Immune system disorders occur when the immune response is inappropriate, excessive/or lacking. Immunodeficiency disorders occur when the immune system fails to fight tumors or invading substances. This causes persistent or recurrent infections, severe infections by organisms that are normally mild, incomplete recovery from illness or poor response to treatment, and an increased incidence of cancer and other tumors. Opportunistic infections are widespread infections by microorganisms that are usually controllable.

This deficiency may affect any part of the immune system. Most commonly, it involves decreased functioning of T or B lymphocytes (or both), or deficient antibody production. The causes include congenital/inherited defects and acquired immunodeficiency caused by a disease that affects the immune system.

Examples of congenital immunodeficiency disorders of antibody production (B lymphocyte abnormalities) include hypogammaglobulinemia (lack of one or more specific antibodies), which usually causes repeated mild respiratory infections, and agammaglobulinemia (lack of all or most antibody production), which results in frequent severe infections and is often fatal. Congenital disorders affecting the T lymphocytes may cause increased susceptibility to fungi, resulting in repeated Candida (yeast) infections. Inherited combined immunodeficiency affects both T lymphocytes and B lymphocytes. It is often fatal within the first year of life because there is no resistance to disease or infection. People are said to be "immunosuppressed" when they experience immunodeficiency that is caused by medications such as corticosteroids or other immunosuppressant medications. This is a desired part of treatment for disorders such as autoimmune disorders. It is used after organ transplantation to prevent transplant rejections.

Immunosuppression is also a common side effect of chemotherapy to treat many types of cancer because the chemotherapy often reduces the number of white blood cells available to fight infection.

Acquired immunodeficiency may be a complication of diseases such as HIV infection and AIDS (acquired immunodeficiency syndrome). Malnutrition, particularly with lack of protein, can cause acquired immunodeficiency. Many cancers can cause immunodeficiency.

Those who have had a splenectomy, or removal of the spleen, face a higher risk of infection from certain encapsulated bacteria, such as but not limited to Streptococcus pneumoniae, that the spleen would normally help fight.

Increasing age also reduces the effectiveness of the immune system. Immune ^"system tissues (particularly lymphoid tissue such as the thymus) shrink with aging. There is also reduced lymphocyte number and activity with increasing age.

The present invention, therefore, is directed in part, to the treatment of immunosuppressed individuals who are suffering from, for example, without limitation, from Ataxia- telangiectasia, DiGeorge syndrome, Chediak-Higashi syndrome, Job syndrome, Leukocyte adehsion defects, Panhypogammaglobulinemia, Bruton disease, Congenital agammaglobulinemia, Selective deficiency of IgA, Combined immunodeficiency disease, Wiscott-Aldrich syndrome, and Complement deficiencies.

Anti-pathogenic agents of the present invention are useful in combating pathogenic infections in animals, including humans. For example, but without limitation, they are potentially useful in treating topical pathogenic infections in man caused by, among other organisms, species of Candida, Trichophyton, Microsporum or Epidermophyton, or in mucosal infections caused by Candida albicans (e.g. thrush and vaginal candidiasis). They may also be used in the treatment of systemic pathogenic infections caused by, for example Candida albicans, Ctyptococcus neoformans, Aspergillus fumigatus, Coccidioides, Paracoccidioides, Histoplasma or Blastomyces spp. They may also be of use in treating eumycotic mycetoma, chromoblastomycosis, and phycomycosis.

In a preferred aspect, the anti-pathogenic compositions of the present invention comprise Amphotericin B and HA.

Amphotericin B is a macrocyclic, polyene compound, and is produced by a strain of Streptomyces nodosus. Amphotericin B is designated chemically as: [1R-(1R*,3S*,5R*,6R*,9R*,11R*,15S*,16R*,17R*,18S*,19E,21E,23E,25E,27E,29E,31E, 33R*,35S*,36R*,37S*)]- 33-[(3-Amino-3,6-dideoxy-(beta)-D-mannopyranosyl)oxy]-

1,3,5,6,9,11,17,37- octahydroxy-15,16,18-trimethyl-13-oxo-14,39-diox-abicyclo[33.3.1] nonatriaconta-19,21,23,25,27,29,31-hepta-ene-36-carboxylic acid (CAS No. 1397-89-3).

Amphotericin B has a molecular formula of C₄₇ H ₃ NO₁₇ and a molecular weight of 924.09.

Although the mechanism of Amphotericin B action is not fully understood, it involves binding to the cell wall, leakage of potassium from the cell and possibly initiation of a lipid peroxidation cascade which irreversibly damages the cell wall of the fungi. It has a substantially greater affinity for ergosterol, present in fungal cell walls, than cholesterol, explaining its greater effects against fungal cells than human cells. However, due to its ability to bind to human cells, it has been shown to induce toxic side effects. Therefore, the present invention is directed to discovery that, combining HA and anti-fungal agents, such as, for example, Amphotericin B, leads to a decrease in the toxic side effects caused by the anti-fungal agent. Determining the appropriate route of administration and dosage of the compounds for use in the methods of the present invention, are generally determined on a case by case basis by the attending physician. Such determinations are routine to one of ordinary skill in the art (see, for example, Harrison's Principles of Internal Medicine (1998), edited by Anthony Fauci et al, 14^th edition, published by McGraw Hill). The routes of administration of the present invention, include, but are not limited to, topical application, oral application, subcutaneous, intravenous, intradermal, or intramuscular injection, percutaneously instilled, and intraspinal.

For oral and parenteral administration to human patients, it is expected that the daily dosage level of an anti-pathogenic compound will be from 0.1 to 1 mg/kg (in divided doses) when administered by either the oral or parenteral route. Thus tablets or capsules can be expected to contain from 5 mg to 0.5 g of active compound for administration singly or two or more at a time as appropriate. The physician in any event will determine the actual dosage that will be most suitable for an individual patient and will vary with the age, weight and response of the particular patient. The above dosages are exemplary of the average case. There can, of course, be individual instances where higher or lower dosage ranges are merited, and such are within the scope of this invention.

For oral administration, the compounds of the present invention can be formulated into solid or liquid preparations such as capsules, pills, tablets, lozenges, powders, suspensions or emulsions. In preparing the compositions in oral dosage form, any of the usual pharmaceutical media may be employed, such as, for example, water, glycols, oils, alcohols, flavoring agents, preservatives, coloring agents, suspending agents, and the like in the case of oral liquid preparations (such as, for example, suspensions, elixirs and solutions); or carriers such as starches, sugars, diluents, granulating agents, lubricants, binders, disintegrating agents and the like in the case of oral solid preparations (such as, for example, powders, capsules and tablets). Because of their ease in administration, tablets and capsules represent the most advantageous oral dosage unit form, in which case solid pharmaceutical carriers are obviously employed. If desired, tablets may be sugar-coated or enteric-coated by standard techniques. The active agent can be encapsulated to make it stable to passage through the gastrointestinal tract while at the same time allowing for passage across the blood brain barrier. See for example, International Patent Publication No. WO 96/11698.

Alternatively, an anti-pathogenic compound can be administered in the form of a suppository or pessary, or it may be applied topically in the form of a lotion, solution, cream, ointment or dusting powder. For example, a compound can be incorporated into a cream consisting of an aqueous emulsion of polyethylene glycols or liquid paraffin; or can be incorporated, at a concentration between 1 and 10%, into an ointment consisting of a white wax or white soft paraffin base together with such stabilizers and preservatives as may be required.

The present invention is further described by the following non-limiting Examples.

EXAMPLE 1 In Vivo model of Renal Toxicity

To determine the effect of HA on the toxicity of anti-pathogenic agents in vivo, the following experiments were performed in rats. Rats were randomly divided into four groups (n = 10), with all groups being pre-bleed on day 0 to determine baseline serum creatinine levels. Animals were then chronically exposed to the following antifungal therapies by administering daily injections for the first 5 days of the 21 -day study: Fungizone (a commercial form of Amphotericin B), HyAMP (HA combined with fungizone formulated with either 824kDa or 1.6xl0⁶ Da HA, Fungizone with HA administered 15 minutes prior to the Fungizone treatment or glucose as a control. In all formulations the dosages of fungizone and HA were 0.75mg/kg and 13.3mg/kg respectively.

When HyAMB (formulated with 824kDa HA) is compared with Fungizone alone, there is a statistically significant decrease in the levels of serum creatinine (Figure 1). Likewise, when HA (824kDa) is administered 15 minutes prior to Amphotericin B, there is a statistically significant decrease in the levels of serum creatinine observed (Figure 1). The protective effect exerted by HA is still evident when amphotericin B is formulated with HA with a molecular mass of 1.6χ 10⁶Da (Figure lb). This finding indicates, that the administration of HA in conjunction with an anti-pathogenic agent, such as Amphotericin B, results in a protective effect against nephrotoxicity. Table 1 compares the levels of disease between the six groups, with histological analysis of both lung and kidney.

These data demonstrate that the combination of an anti-pathogenic agent and HA prevents the otherwise predictable nephrotoxicity of the mainstream antifungal agent, Amphotericin By overcoming renal impairment typically observed during standard dose antifungal therapy, HyAMP allows the completion of current treatment protocols and may permit the administration of higher dosages and /or for longer periods. Table 1 : Analysis of Amp B and HA treated rats. AMPHOTERECIN TREATED RATS

EXAMPLE 2 The Potency of Anti-pathogenic Agents Is Not Attenuated In the Presence Of HA

These experiments exemplify the finding that co-administration of an anti-pathogenic agent in the presence of HA does not diminish the potency of the anti-pathogenic agent.

In order to perform these studies, female immunocompetent Balb/c mice were challenged intravenously with 2.5x10⁶ viable Candida albicans (C. albicans). At day 3 and 10 after challenge mice received the following treatments: 1. Fungizone (0.75mg/kg) 2. HyAMP (0.75mg/kg amphotericin B; HA 13.3mg/kg [824kDa]) 3. HyAMP (1.5mg/kg amphotericin B; HA 13.3mg/kg [824kDa]) 4. Ambisome (l.Omg/kg) 5. Ambisome ( 1.5mg/kg) 6. HyAMP (l.Omg/kg amphotericin B; HA 13.3mg/kg [1.6x 10⁶Da]) 7. CONTORLS: Saline HA (13.3mg/kg) prepared in 5% w/v glucose solution.

On day 21 the tissue burden of C.albicans was determined by preparing tissue homogenates of kidneys, which were serially diluted then plated onto Sabouraud agar plates. Following incubation at 37°C for 48hours, the total number of colonies were counted and expressed as log₁₀ colony forming units (CFU) per organ. The data described in Figure 2 demonstrate that the potency of Fungizone is not diminished in the presence of HA.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features. BIBLIOGRAPHY:

Medoff, G., Kabayashi, G., New England Journal of Medicine 302:145-55, 1980

Cohen, J., Lancet ii:532-31, 1982

Graybill, J. R., Craven, P. C, Drugs 25:41-62, 1983

Fauci, A (Ed), Harrison's Principles of Internal Medicine, 14^th Ed., McGraw Hill, 1998

Claims

CLAIMS:

1. A method for treating a pathogenic infection in a subject said method comprising administering a therapeutically effective amount of a composition comprising an anti-pathogenic agent and modified or non-modified hyaluronan (HA).

2. The method of Claim 1, wherein in said anti-pathogenic agent is selected from the group consisting of an anti -viral, anti-fungal and an anti -bacterial agent.

3. The method according to Claim 2, wherein said anti-fungal agent is selected from the group consisting of Clotrimazole, Fluconazole, Flucytosine, Itraconazole, Ketoconazole and Nystatin.

4. The method of Claim 2, wherein said anti-fungal agent is an amphotericin polyene macrolide.

5. The method of Claim 4, wherein said amphotericin polyene macrolide is Amphotericin B.

6. The method of Claim 2, wherein said anti -viral agent is selected from the group consisting of 3TC, Abacavir, Acyclovir, Alpha interferon, AZT, Bleomycin, Capreomycin, Cidofovir, Ciprofloxacin, Cyclophosphamide, ddC, ddi, Delavirdine, Didanosine, Dronabinol, Efavirenz, Erythropoetin, Famciclovir, Filgrastim, Foscarnet, Ganciclovir, Ganciclovir Implants, Indinavir, Lamivudine, Lopinavir, Megace, Methotrexate, Nelfinavir, Nevirapine, Nonoxynol-9, Ribavirin, Ritonavir, Saquinavir, Stavudine, Sulfamethoxazole, Tenofovir, Trimethoprim, Zalcitabine and Zidovudine.

7. The method of Claim 2, wherein said anti-bacterial agent is selected from the group consisting of Amikacin, Atovaquone, Azithromycin, Clarithromycin, Clindamycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, IVIG, Kanamycin, Metronidazole, Ofloxacin, Para Aminosalicyclic Acid, Pentamidine, Primaquine, Pyrazinamide, Pyrimethamine, Rifabutin, Rifampin, Streptomycin, Sulfadiazine, Sulfadoxine, Sulfamethazine, Trimetrexate, Triple Sulfa.

8. The method of claim any one of Claims 1 to 7, wherein said HA has a modal molecular weight range from about 50,000 to 20,000,000 Da.

9. The method of Claim 8, wherein in said molecular weight is from about 750,000 to 1,000,000 Da.

10. The method of Claim 1 wherein said pathogenic infection is caused by a fungi selected from the group consisting Acremonium spp., Aspergillus spp., Basidiobolus spp., Bipolaris spp., Blastomyces dermatidis, Candida spp., Cladophialophora carrionii, Coccoidiodes immitis, Conidiobolus spp., Cryptococcus spp., Curvularia spp., Epidermophyton spp., Exophiala jeanselmei, Exserohilum spp., Fonsecaea compacta, Fonsecaea pedrosoi, Fusarium oxysporum, Fusarium solani, Geotrichum candidum, Histoplasma capsulatum var. capsulatum, Histoplasma capsulatum var. duboisii, Hortaea werneckii, Lacazia loboi, Lasiodiplodia theobromae, Leptosphaeria senegalensis, Madurella grisea, Madurella mycetomatis, Malassezia furfur, Microsporum spp., Neotestudina rosatii, Onychocola canadensis, Paracoccidioides brasiliensis, Phialophora verrucosa, Piedraia hortae, Piedra iahortae, Pityriasis versicolor, Pseudallesheria boydii, Pyrenochaeta romeroi, Rhizopus arrhizus, Scopulariopsis brevicaulis, Scytalidium dimidiatum, Sporothrix schenckii, Trichophyton spp., Trichosporon spp., Zygomcete fungi, Absidia corymbifera, Rhizomucor pusillus, and Rhizopus arrhizus.

11. The method of any one of Claims 1 to 10, wherein said anti-pathogenic agent and HA are simultaneously administered.

12. The method of any one of Claims 1 to 10, wherein said HA is administered from about 24 hours to about 5 minutes before or after said anti-pathogenic agent.

13. The method of any one of Claims 1 to 10, wherein said HA is administered from about 12 hours to about 10 minutes before or after said anti-pathogenic agent.

14. The method of any one of Claims 1 to 10, wherein said HA is administered about half an hour before or after said anti-pathogenic agent.

15. The method of any one of Claims 1 to 10, wherein said HA is administered about 15 minutes before or after said anti-pathogenic agent.

16. The method of any one of Claims 1 to 15, wherein said effective amount of HA is from about 0.5mg to about 20mg per kilogram body weight pre day.

17. The method of any one of Claims 1 to 15, wherein said effective amount of HA is from about 5mg to about lOmg per kilogram body weight per day.

18. A method of treating an immunocompromised subject wherein said patient has a pathogenic infection, said method comprising administering a therapeutically effective amount of an anti-pathogenic agent and modified or non-modified HA.

19. The method of Claim 18, wherein in said anti-pathogenic agent is selected from the group consisting of an anti-viral, anti-fungal and an anti-bacterial agent.

20. The method according to Claim 19, wherein said anti-fungal agent is selected from the group consisting of Clotrimazole, Fluconazole, Flucytosine, Itraconazole, Ketoconazole and Ny statin.

21. The method of Claim 19, wherein said anti-fungal agent is an amphotericin polyene macrolide.

22. The method of Claim 21, wherein said amphotericin polyene macrolide is Amphotericin B.

23. The method of Claim 19, wherein said anti-viral agent is selected from the group consisting of 3TC, Abacavir, Acyclovir, Alpha interferon, AZT, Bleomycin, Capreomycin, Cidofovir, Ciprofloxacin, Cyclophosphamide, ddC, ddi, Delavirdine, Didanosine, Dronabinol, Efavirenz, Erythropoetin, Famciclovir, Filgrastim, Foscarnet, Ganciclovir, Ganciclovir Implants, Indinavir, Lamivudine, Lopinavir, Megace, Methotrexate, Nelfinavir, Nevirapine, Nonoxynol-9, Ribavirin, Ritonavir, Saquinavir, Stavudine, Sulfamethoxazole, Tenofovir, Trimethoprim, Zalcitabine and Zidovudine.

24. The method of Claim 19, wherein said anti-bacterial agent is selected from the group consisting of Amikacin, Atovaquone, Azithromycin, Clarithromycin, Clindamycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, IVIG, Kanamycin, Metronidazole, Ofloxacin, Para Aminosalicyclic Acid, Pentamidine, Primaquine, Pyrazinamide, Pyrimethamine, Rifabutin, Rifampin, Streptomycin, Sulfadiazine, Sulfadoxine, Sulfamethazine, Trimetrexate, Triple Sulfa.

25. The method of claim any one of Claims 18 to 24, wherein said HA has a modal molecular weight range from about 50,00 to 20,000,000 Da.

26. The method of Claim 25, wherein in said molecular weight is from about 750,000 to 1,000,000 Da.

27. The method of Claim 18 wherein said pathogenic infection is caused by a fungi selected from the group consisting Acremonium spp., Aspergillus spp., Basidiobolus spp., Bipolaris spp., Blastomyces dermatidis, Candida spp., Cladophialophora carrionii, Coccoidiodes immitis, Conidiobolus spp., Cryptococcus spp., Curvularia spp., Epidermophyton spp., Exophiala jeanselmei, Exserohilum spp., Fonsecaea compacta, Fonsecaea pedrosoi, Fusarium oxysporum, Fusarium solani, Geotrichum candidum, Histoplasma capsulatum var. capsulatum, Histoplasma capsulatum var. duboisii, Hortaea werneckii, Lacazia loboi, Lasiodiplodia theobromae, Leptosphaeria senegalensis, Madurella grisea, Madurella mycetomatis, Malassezia furfur, Microsporum spp., Neotestudina rosatii, Onychocola canadensis, Paracoccidioides brasiliensis, Phialophora verrucosa, Piedraia hortae, Piedra iahortae, Pityriasis versicolor, Pseudallesheria boydii, Pyrenochaeta romeroi, Rhizopus arrhizus, Scopulariopsis brevicaulis, Scytalidium dimidiatum, Sporothrix schenckii, Trichophyton spp., Trichosporon spp., Zygomcete fungi, Absidia corymbifera, Rhizomucor pusillus, and Rhizopus arrhizus.

28. The method of any one of Claims 18 to 27, wherein said anti-pathogenic agent and HA are simultaneously administered.

29. The method of any one of Claims 18 to 27, wherein said HA is administered from about 24 hours to about 5 minutes before or after said anti-pathogenic agent.

30. The method of any one of Claims 18 to 27, wherein said HA is administered . from about 12 hours to about 10 minutes before or after said anti-pathogenic agent.

31. The method of any one of Claims 18 to 27, wherein said HA is administered about half an hour before or after said anti-pathogenic agent.

32. The method of any one of Claims 18 to 27, wherein said HA is administered about 15 minutes before or after said anti-pathogenic agent.

33. The method of any one of Claims 18 to 32, wherein said effective amount of HA is from about 0.5mg to about 20mg per kilogram body weight pre day.

34. The method of any one of Claims 18 to 32, wherein said effective amount of HA is from about 5mg to about lOmg per kilogram body weight pre day.

35. The use of an anti-pathogenic agent and modified or non-modified HA in the manufacture of a medicament in the treatment of a pathogenic infection.

36. The use of Claim 35, wherein said anti-pathogenic agent is selected from the group consisting of an anti-fungal, anti -viral and an anti-bacterial agent.

37. The use of Claim 36, wherein said anti-fungal agent is selected from the group consisting of Clotrimazole, Fluconazole, Flucytosine, Itraconazole, Ketoconazole and Nystatin.

38. The use of Claim 36, wherein said anti-fungal agent is an amphotericin polyene macrolide.

39. The use of Claim 38, wherein said amphotericin polyene macrolide is Amphotericin B.

40. The use of Claim 36, wherein said anti-viral agent is selected from the group consisting of 3TC, Abacavir, Acyclovir, Alpha interferon, AZT, Bleomycin, Capreomycin, Cidofovir, Ciprofloxacin, Cyclophosphamide, ddC, ddi, Delavirdine, Didanosine, Dronabinol, Efavirenz, Erythropoetin, Famciclovir, Filgrastim, Foscarnet, Ganciclovir, Ganciclovir Implants, Indinavir, Lamivudine, Lopinavir, Megace, Methotrexate, Nelfinavir, Nevirapine, Nonoxynol-9, Ribavirin, Ritonavir, Saquinavir, Stavudine, Sulfamethoxazole, Tenofovir, Trimethoprim, Zalcitabine and Zidovudine.

41. The use of Claim 36, wherein said anti-bacterial agent is selected from the group consisting of Amikacin, Atovaquone, Azithromycin, Clarithromycin, Clindamycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, IVIG, Kanamycin, Metronidazole, Ofloxacin, Para Aminosalicyclic Acid, Pentamidine, Primaquine, Pyrazinamide, Pyrimethamine, Rifabutin, Rifampin, Streptomycin, Sulfadiazine, Sulfadoxine, Sulfamethazine, Trimetrexate, Triple Sulfa.

42. The use of any one of Claims 35 to 41, wherein said HA has a modal molecular weight range from about 50,00 to 20,000,000 Da.

43. The use of Claim 42, wherein in said molecular weight is from about 750,000 to 1,000,000 Da.

44. The use of Claim 35 wherein said pathogenic infection is caused by a fungi selected from the group consisting Acremonium spp., Aspergillus spp., Basidiobolus spp., Bipolaris spp., Blastomyces dermatidis, Candida spp., Cladophialophora carrionii, Coccoidiodes immitis, Conidiobolus spp., Cryptococcus spp., Curvularia spp., Epidermophyton spp., Exophiala jeanselmei, Exserohilum spp., Fonsecaea compacta, Fonsecaea pedrosoi, Fusarium oxysporum, Fusarium solani, Geotrichum candidum, Histoplasma capsulatum var. capsulatum, Histoplasma capsulatum var. duboisii, Hortaea werneckii, Lacazia loboi, Lasiodiplodia theobromae, Leptosphaeria senegalensis, Madurella grisea, Madurella mycetomatis, Malassezia furfur, Microsporum spp., Neotestudina rosatii, Onychocola canadensis, Paracoccidioides brasiliensis, Phialophora verrucosa, Piedraia hortae, Piedra iahortae, Pityriasis versicolor, Pseudallesheria boydii, Pyrenochaeta romeroi, Rhizopus arrhizus, Scopulariopsis brevicaulis, Scytalidium dimidiatum, Sporothrix schenckii, Trichophyton spp., Trichosporon spp., Zygomcete fungi, Absidia corymbifera, Rhizomucor pusillus, and Rhizopus arrhizus.

45. The use of any one of Claims 35 to 44, wherein said anti-pathogenic agent and HA are simultaneously administered.

46. The method of any one of Claims 35 to 44, wherein said HA is administered from about 24 hours to about 5 minutes before or after said anti-pathogenic agent.

47. The method of any one of Claims 35 to 44, wherein said HA is administered from about 12 hours to about 10 minutes before or after said anti-pathogenic agent.

48. The method of any one of Claims 35 to 44, wherein said HA is administered about half an hour before or after said anti-pathogenic agent.

49. The use of any one of Claims 35 to 44, wherein said HA is administered about 15 minutes before or after said anti-pathogenic agent.

50. The use of any one of Claims 35 to 49, wherein the effective amount of HA is from about 0.5mg to about 20mg per kilogram body weight pre day.

51. The use of any one of Claims 35 to 49, wherein the effective amount of HA is from about 5mg to about 1 Omg per kilogram body weight pre day.

52. A pharmaceutical composition comprising modified or non-modified HA and an anti-pathogenic compound together with one or more pharmaceutically acceptable carriers or diluents.

53. The pharmaceutical composition of Claim 52 wherein said anti-pathogenic agent is selected from the group consisting of an anti-fungal, anti-viral and an antibacterial agent.

54. The pharmaceutical composition of Claim 53, wherein said anti-fungal agent is selected from the group consisting of Clotrimazole, Fluconazole, Flucytosine, Itraconazole, Ketoconazole and Nystatin.

55. The pharmaceutical composition of Claim 54, wherein said anti-fungal agent is a polyene macrolide.

56. The pharmaceutical composition of Claim 55, wherein said polyene macrolide is Amphotericin B.

57. The pharmaceutical composition of Claim 53, wherein said anti-viral agent is selected from the group consisting of 3TC, Abacavir, Acyclovir, Alpha interferon, AZT, Bleomycin, Capreomycin, Cidofovir, Ciprofloxacin, Cyclophosphamide, ddC, ddi, Delavirdine, Didanosine, Dronabinol, Efavirenz, Erythropoetin, Famciclovir, Filgrastim, Foscarnet, Ganciclovir, Ganciclovir Implants, Indinavir, Lamivudine, Lopinavir, Megace, Methotrexate, Nelfinavir, Nevirapine, Nonoxynol-9, Ribavirin, Ritonavir, Saquinavir, Stavudine, Sulfamethoxazole, Tenofovir, Trimethoprim, Zalcitabine and Zidovudine.

58. The pharmaceutical composition of Claim 53, wherein said anti-bacterial agent is selected from the group consisting of Amikacin, Atovaquone, Azithromycin, Clarithromycin, Clindamycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, IVIG, Kanamycin, Metronidazole, Ofloxacin, Para Aminosalicyclic Acid, Pentamidine, Primaquine, Pyrazinamide, Pyrimethamine, Rifabutin, Rifampin, Streptomycin, Sulfadiazine, Sulfadoxine, Sulfamethazine, Trimetrexate, Triple Sulfa.

59. The pharmaceutical composition of any one of Claims 52 to 58, wherein said HA has a modal molecular weight range from about 50,000 to 20,000,000 Da.

60. The pharmaceutical composition of Claim 59, wherein in said molecular weight is from about 750,000 to 1,000,000 Da.