Cyclic dofovir or prodrug thereof for treating or preventing African swine fever

Abstract

Provided herein are cyclodofovir for use in the treatment of African swine fever (ASF) in an animal, comprising orally administering the cyclodofovir at a dose of 10.0 to 30.0 mg / kg wherein at least one dose, such as one or two doses, is administered daily to the animal in a first period of consecutive 1 to 4 days, and administering to the animal one dose of cyclodofovir every other day or day in a second period of time of consecutive 5 to 14 days, and wherein the average daily dose administered in the first period of time is higher than the average daily dose administered in the second period of time.

Description

Field of the Invention

[0001] The present invention relates to methods for treating or preventing African swine fever and compositions for use therein. Background Art

[0002] 40% of the world's meat consumption is pork, with Europe being the world's second largest pork producer (approximately 150 million pigs). However, due to the industrial system characterized by the rearing of large numbers of animals, mostly in confined spaces, with rapid herd turnover at a single location, the meat industry is vulnerable to viral disease outbreaks, which can lead to huge economic losses, threaten food security, and cause animal suffering.

[0003] Over the past decade, African swine fever (ASF) has spread from the Caucasus region to European countries, affecting both domestic and wild boar populations. ASF is a highly contagious and deadly disease of pigs. More specifically, ASF in domestic pigs has a mortality rate of up to 100% and is characterized by high fever, depression, loss of appetite, vomiting, and bleeding in the skin and internal organs.

[0004] Currently, there is no effective vaccine or treatment for ASF, and only strict adherence to control measures can prevent the introduction and spread of ASF to domestic pig farms. Important control measures include identification of animals and farm records, isolation of pigs to not allow direct or indirect contact between pigs and / or pigs and wild boars, and proper disposal of feces and dead animals. Therefore, ASF is a serious constraint to the development of both smallholder and industrial pig farming.

[0005] Therefore, there is a need to develop effective means to prevent the spread of ASF. Summary of the invention

[0006] To the best of the inventors' knowledge, the inventors are the first to demonstrate the in vivo efficacy of phosphonic acid nucleosides, more particularly cycliccidofovir, in the treatment (defined herein to cover the treatment and prevention of disease) of animals (more particularly pigs) infected with African swine fever virus (ASFV). In addition, the inventors have tested several dosage regimens and have found specific dosage ranges and specific dosage regimens of cyclocidofovir or its prodrugs that allow the treatment (including the prevention of disease) of animals (more particularly pigs) infected with ASFV. More particularly, the inventors have found a dosage regimen comprising two subsequent time periods, wherein the dose and / or time of administration in the first time period is different from the dose and / or time in the second time period, preferably wherein the average daily dose administered in the first time period is higher than the average daily dose administered in the second time period, which reduces viral shedding and clinical symptoms of the disease and improves the survival rate of pigs challenged by ASFV, while allowing cyclocidofovir or the prodrug to have acceptable toxicity or absence of toxicity.

[0007] Therefore, a first aspect provides a cyclocidofovir for treating African swine fever (ASF) in an animal, comprising orally administering the cyclocidofovir at a dose of 10.0 to 30.0 mg / kg, wherein at least one dose of cyclocidofovir (such as one or two doses) is administered daily to the animal in a first period of 1 to 4 consecutive days, and a dose of cyclocidofovir is administered to the animal every other day or daily in a second period of 5 to 14 consecutive days, and wherein the average daily dose administered in the first period is higher than the average daily dose administered in the second period. In a particular embodiment, the cyclocidofovir contemplated for use herein is a compound of formula (i):

[0008]

[0009] or an ester, an amidate or an esteramidate thereof, more particularly an acyloxyalkyl ester, an alkoxycarbonyloxyalkyl ester, an alkoxyalkyl ester or a phosphoramidate or phosphonamidite thereof.

[0010] In some embodiments, the cyclocidofovir used according to the present invention has the structure of formula (I) or (II),

[0011]

[0012] in,

[0013] A is selected from the group consisting of O and NH;

[0014] L chooses from -(CR 2 R 3 )n -、-CH(R 4 )-C(O)- and -C(O)-CH(R 5 )-groups composed of;

[0015] n is an integer selected from 1, 2, 3, 4 or 5;

[0016] R 1 Choose from C 6-25 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-25 Haloalkyl, C 6-25 Alkenyl, C 6-25 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 The group consisting of halocycloalkyl;

[0017] Each R 2 are independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0018] Each R 3 are independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0019] Each R 4 are independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0020] Each R 5 are independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0021] Each R 6 Independently selected from C 1-10 Alkyl, C 1-10 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups;

[0022] Each R 7 Independently selected from C 1-10 Alkyl, C 1-12 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups;

[0023] or stereoisomers, tautomers, solvates, hydrates, or pharmaceutically acceptable salts thereof.

[0024] In some embodiments, cyclocidofovir used according to the present invention has the structure of formula (I), wherein

[0025] L chooses from -(CR 2 R 3 ) n - and -CH(R 4 )-C(O)-;

[0026] n is an integer selected from 1, 2 or 3;

[0027] R 1 Choose from C 6-25 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-25 Haloalkyl, C 6-25 Alkenyl and C 3-10 A group consisting of cycloalkyl groups;

[0028] Each R 2 are independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen;

[0029] Each R 3 are independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen;

[0030] Each R 4 are independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen;

[0031] Each R 5 are independently selected from hydrogen, C 1-6 Alkyl, C 3-10 The group consisting of cycloalkyl and halogen;

[0032] Each R 6 Independently selected from C 1-6 Alkyl, C 1-6 Haloalkyl and C 3-6 A group consisting of cycloalkyl groups;

[0033] Each R 7 Independently selected from C 1-6 Alkyl, C 1-6 Haloalkyl and C 3-6 A group consisting of cycloalkyl.

[0034] In some embodiments, the cyclocidofovir used according to the present invention is selected from the group consisting of:

[0035]

[0036] In a particular embodiment, the animal is administered two doses of ciclocidofovir daily for a first period of 3 consecutive days and one dose of ciclocidofovir daily for a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days.

[0037] In a particular embodiment, the animal is administered a dose of ciclocidofovir daily for a first period of 3 consecutive days and is administered a dose of ciclocidofovir every other day for a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days.

[0038] In a particular embodiment, ciclocidofovir is contained in a pharmaceutical composition, preferably wherein the pharmaceutical composition is an aqueous solution.

[0039] In particular embodiments, the animal is a pig.

[0040] In particular embodiments, the animals are housed in an ASF surveillance or conservation area.

[0041] In particular embodiments, the administration of ciclocidofovir prevents the spread of ASF in an animal population. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A general outline of the VV03-0035 challenge study in pigs as described in Example 5. Key study time points and major study results are depicted.

[0044] Figure 2 .Survival curves for control and treated pigs in the VV03-0035 challenge study as described in Example 5 are shown. The x-axis shows the number of days after ASFV challenge. The y-axis shows the percentage of pigs surviving past the moderate severity humane endpoint each day. The median survival of the control group was calculated to be 6 days, and the median survival of the treatment group was calculated to be 19.5 days.

[0045] Figure 3 ASFV genome copy number in whole blood isolated from control pigs (C1 to C3) and treated pigs (T4 to T9). Viral genome copies were measured by quantitative qPCR and expressed as log 10 It is expressed as genome copies / ml blood.

[0046] Figure 4ASFV genome copy numbers in nasal, oral, and rectal swab samples collected from control pigs (C1 to C3) and treated pigs (T4 to T9). Viral genome copies were measured by quantitative qPCR and expressed as log 10 It is expressed as genome copies / ml.

[0047] Figure 5 .Survival curves for control and treated pigs in the VV03-0035 challenge study as described in Example 6 are shown. The x-axis shows the number of days after ASFV challenge. The y-axis shows the percentage of pigs that survived past the moderate severity humane endpoint each day. The median survival for the control group was calculated to be 5.5 days, and the median survival for the treatment group was calculated to be 8 days. The difference was statistically significant as determined by the log-rank (Mantel-Cox) test and the Gehan-Breslow-Wilcoxon test, with p values ​​of 0.0010 and 0.0016, respectively.

[0048] Figure 6 Results for tissue samples collected at necropsy, including spleen, lung, submandibular lymph node (SMLN), renal lymph node (RNL), and gastrohepatic lymph node (GHLN). Results for individual pigs in the control or treatment groups are shown on separate columns, and each figure compares the results for the tissues shown. In the case of comparisons of control pigs to treated pigs, significance was determined by nested t-tests (*p≤0.05, ***p≤0.001).

[0049] Figure 7 ASFV genome copy number in whole blood isolated from control pigs (C1 to C6) and treated pigs (T1 to T6). Viral genome copies were measured by quantitative qPCR and expressed as log 10 Genome copies / ml blood are expressed. In the case of comparison of control pigs with treated pigs, significance was determined by nested t-test (*p≤0.05, ***p≤0.001).

[0050] Figure 8.Shows a photograph of a microplate in which the expression of green fluorescent protein of porcine bone marrow cells infected with recombinant ASFV genotype II Georgia virus GeorgiaDMGFB (expressing mNeon green fluorescent protein) can be observed. Part A shows the results (i.e., expression of green fluorescent protein) when porcine bone marrow cells infected with ASFV were exposed to no compound (columns 1, 2, and 3), compound 3 (columns 4, 5, and 6), compound 4 (columns 7, 8, and 9), or cHPMPC (columns 10, 11, and 12). The final concentrations of the test compounds were: A: 1.0 μM, B: 0.5 μM, C: 0.1 μM, D: 0.05 μM, E: 0.01 μM, F: 0.005 μM, G 0.001 μM. Part B shows the results when porcine bone marrow cells infected with ASFV were exposed to no compound (columns 1, 2, and 3), compound 1 (columns 4, 5, and 6), compound 2 (columns 7, 8, and 9), or compound 5 (columns 10, 11, and 12). The final concentrations of the test compounds were: A: 1.0 μM, B: 0.5 μM, C: 0.1 μM, D: 0.05 μM, E: 0.01 μM, F: 0.005 μM, G 0.001 μM. DETAILED DESCRIPTION OF THE INVENTION

[0052] When used in relation to a numerical value, the term "about" has the meaning generally understood in the relevant art. In certain embodiments, the term "about" may be omitted or may be interpreted to mean a numerical value + 10%; or + 5%; or + 2%; or + 1%.

[0053] Whenever used herein in relation to percentages, w / w means weight / weight and w / v means weight / volume.

[0054] As used herein, the singular form "a," "an," and "the" include both singular and plural referents unless the context clearly dictates otherwise.

[0055] As used herein, the terms "comprising / comprises / comprised of" are synonymous with "including / includes" or "containing / contains", and are inclusive or open-ended, and do not exclude additional, unrecited members, elements, or method steps. When referring to the recited members, elements, or method steps, the terms "comprising / comprises / comprised of" also include embodiments that "consists of" the recited members, elements, or method steps.

[0056] Furthermore, in the specification and claims, the terms first, second, third, etc. are used to distinguish similar elements or steps, and are not necessarily used to describe a sequential or chronological order unless otherwise specified. It should be understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments described herein are capable of operating in other sequences than those described or illustrated herein.

[0057] Throughout this specification, references to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment contemplated by the present invention. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment, but may refer to the same embodiment. From the outside, particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments, as will be apparent to those skilled in the art based on this disclosure. In addition, although some embodiments described herein include some features included in other embodiments but do not include other features, the combination of features of different embodiments is intended to be within the scope of the present invention and to form different embodiments, as will be understood by those skilled in the art. For example, in the appended claims, any of the embodiments claimed for protection may be used in any combination.

[0058] Any references cited herein are hereby incorporated by reference.

[0059] To the best of the inventors' knowledge, the inventors are the first to demonstrate the in vivo efficacy of phosphonic acid nucleosides in the treatment (defined herein as covering treatment and prevention) of animals (more particularly pigs) infected with African swine fever virus (ASFV). In addition, the inventors have tested several dosage regimens and have found specific dosage ranges and specific dosage regimens of cyclocidofovir or its prodrugs that allow for the treatment (including prevention of disease) of animals (more particularly pigs) infected with ASFV. More particularly, the inventors have found a dosage regimen comprising two subsequent time periods, wherein the dose and / or time of administration in the first time period is different from the dose and / or time in the second time period, preferably wherein the average daily dose administered in the first time period is higher than the average daily dose administered in the second time period, which reduces viral shedding and clinical symptoms of the disease and improves the survival rate of pigs attacked by ASFV, while allowing cyclocidofovir or prodrugs to have acceptable toxicity or absence of toxicity.

[0060] Therefore, the first aspect provides a kind of cyclocidofovir or its prodrug, and the cyclocidofovir or its prodrug is used to treat African swine fever (ASF) in animals, including 10.0 to 30.0mg / kg, preferably 15.0 to 25.0mg / kg, such as about 20.0mg / kg, wherein the cyclocidofovir or its prodrug is orally administered to the animal in a first time period of 1 to 4 consecutive days, at least one dose of the cyclocidofovir or its prodrug (such as one or two doses) is administered to the animal daily, and at least 5 consecutive days, such as 5 to 14 consecutive days, in a second time period, the animal is administered a dose of cyclocidofovir every other day or daily, wherein the average daily dose administered in the first time period is higher than the average daily dose administered in the second time period. Here, "mg / kg" refers to the amount of cyclocidofovir or its prodrug / kg animal body weight. In addition, the average daily dose takes into account the total dose administered in the time period and the total number of days in the time period. For example, for a period of 5 consecutive days, wherein an animal is administered 20.0 mg / kg of ciclocidofovir every other day, and the period begins on the day of administration, the average daily dose is 12.0 mg / kg (ie, (20.0 mg / kg*3) / 5).

[0061] Another aspect provides a method of treating (defined herein to cover both treatment and prevention) ASF in an animal, the method comprising orally administering cyclocidofovir or a prodrug thereof at a dose of 10.0 to 30.0 mg / kg, wherein at least one dose of cyclocidofovir (such as one or two doses) is administered to the animal daily over a first period of 1 to 4 consecutive days, and a dose of cyclocidofovir is administered to the animal every other day or daily over a second period of at least 5 consecutive days, such as 5 to 14 consecutive days, and wherein the average daily dose administered in the first period is higher than the average daily dose administered in the second period.

[0062] Another aspect provides the use of cyclocidofovir or a prodrug thereof in the preparation of a medicament for treating (defined herein to cover both treatment and prevention) ASF in an animal, wherein the cyclocidofovir or a prodrug thereof is orally administered at a dose of 10.0 to 30.0 mg / kg, wherein at least one dose of cyclocidofovir (such as one or two doses) is administered to the animal daily over a first period of 1 to 4 consecutive days, and a dose of cyclocidofovir is administered to the animal every other day or daily over a second period of at least 5 consecutive days, such as 5 to 14 consecutive days, and wherein the average daily dose administered in the first period is higher than the average daily dose administered in the second period.

[0063] As used herein, the term "cyclocidofovir", "cCDV", "cyclo(S)-HPMPC" or "cHPMPC" refers to a compound having the following structural formula:

[0064]

[0065] or any derivative thereof. cHPMPC is annotated in the PubChem database as PubChem CID 122873.

[0066] Thus, as used herein, the term "cyclocidofovir", "cCDV" or "cHPMPC" encompasses isomers, solvates, tautomers, salts, esters, amides, esteramidates or pharmaceutically acceptable salts of compounds of formula (i) above, or compounds in equilibrium with the compounds of the formula described above. The phosphonate functionality of the nucleoside analogs can be derivatized to increase activity, pharmacokinetic properties or pharmacodynamic properties. Thus, the term "cyclocidofovir", "cCDV" or "cHPMPC" also encompasses phosphonates, amides or esteramidates of compounds of formula (i), wherein the phosphonate can be monosubstituted or disubstituted. Examples of such esters include alkyl esters, alkenyl esters, alkynyl esters, alkoxyalkyl esters, alkoxyalkenyl esters, such as octyl, tetracosyl, hexadecyloxypropyl, octadecyloxyethyl, oleyloxypropyl, tetradecyloxypropyl, octadecyloxypropyl, oleyloxyethyl, 1-O-octadecyl-2-O-benzyl-glyceryl, etc. Cyclocidofovir can be prepared by any method known in the art, such as, for example, described in International Patent Application WO 9507919 A1.

[0067] Further suitable examples of esters, amidates or esteramidates of compounds of formula (i) include acyloxyalkyl esters, alkoxycarbonyloxyalkyl esters, alkoxyalkyl esters or amidates such as phosphoamidates or phosphonamidates (also known as ProTides).

[0068] As used herein, the term "prodrug" refers to a drug or compound that is metabolized into a pharmacologically active compound after being administered to a subject. Prodrugs can improve the way in which pharmacologically active compounds are absorbed, distributed, metabolized and excreted (ADME) by the subject's body. Cyclocidofovir itself is considered to be a prodrug of HPMPC (cidofovir).

[0069] However, other prodrugs may be considered. For example, the prodrug of cyclocidofovir may be a prodrug of cyclocidofovir described in Pertusat F. et al., Medicinal Chemistry of NucleosidePhosphonateProdrugs for Antiviral Therapy, Antiviral Chemistry and Chemotherapy, 2012, such as a phenyl or salicylate prodrug or a serine peptide phosphate or alkoxycarbonylphenyl prodrug of cyclocidofovir or a peptide conjugate of cyclocidofovir, such as described in International Patent Application WO 2006014429A2.

[0070] In a particular embodiment, cyclocidofovir is selected from the group consisting of pivaloyloxymethyl cyclocidofovir, isopropoxycarbonyloxymethyl cyclocidofovir, L-alanine isopropyl cyclocidofovir, L-valine isopropyl cyclocidofovir, 1-O-hexadecylpropylene glycol-3-cyclocidofovir, 1-O-octadecylpropylene glycol-3-cyclocidofovir, 1-O-octadecylethylene glycol-2-cyclocidofovir, hexadecyloxypropyl cyclocidofovir, octadecyloxyethyl cyclocidofovir, oleyloxypropyl cyclocidofovir, octyl Oxypropyl cyclocidofovir, dodecyloxypropyl cyclocidofovir, oleyloxyethyl cyclocidofovir, 1-O-octadecyl-2-O-benzyl-glyceryl cyclocidofovir, tetradecyloxypropyl cyclocidofovir, eicosyl cyclocidofovir, docosyl cyclocidofovir and hexadecyl cyclocidofovir, preferably the cyclocidofovir prodrug is selected from the group consisting of pivaloyloxymethyl cyclocidofovir, isopropoxycarbonyloxymethyl cyclocidofovir, L-alanine isopropyl cyclocidofovir and L-valine isopropyl cyclocidofovir.

[0071] In some embodiments, the cyclocidofovir used according to the present invention has the structure of formula (I) or (II),

[0072]

[0073] in,

[0074] A is selected from the group consisting of O and NH;

[0075] L chooses from -(CR 2 R 3 ) n -、-CH(R 4 )-C(O)- and -C(O)-CH(R 5 )-groups composed of;

[0076] n is an integer selected from 1, 2, 3, 4 or 5;

[0077] R 1 Choose from C 6-25 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-25 Haloalkyl, C 6-25 Alkenyl, C 6-25 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 The group consisting of halocycloalkyl;

[0078] Each R 2 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0079] Each R 3 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0080] Each R 4 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0081] Each R 5 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen;

[0082] Each R 6 Independently selected from C 1-10 Alkyl, C 1-10 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups;

[0083] Each R 7 Independently selected from C 1-10 Alkyl, C 1-12 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups;

[0084] or stereoisomers, tautomers, solvates, hydrates, or pharmaceutically acceptable salts thereof.

[0085] The term "halo" or "halogen" as a group or part of a group is a generic term for fluorine, chlorine, bromine, and iodine.

[0086] The term "alkyl", as a group or part of a group, refers to a group of the formula -C n H 2n+1 wherein n is a number greater than or equal to 1. The alkyl group may be straight or branched, and may be substituted, as indicated herein. Typically, the alkyl groups of the present invention contain up to 25 carbon atoms, preferably up to 24 carbon atoms, preferably up to 23 carbon atoms, more preferably up to 22 carbon atoms, and even more preferably up to 21 carbon atoms. When a subscript is used after a carbon atom herein, the subscript refers to the number of carbon atoms that the named group may contain. For example, "C 1-6 "Alkyl" includes all straight or branched alkyl groups having 1 to 6 carbon atoms, and thus includes methyl, ethyl, n-propyl, isopropyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof, hexyl and isomers thereof. For example, "C 1-5 "Alkyl" includes all straight or branched alkyl groups having 1 to 5 carbon atoms, and thus includes methyl, ethyl, n-propyl, isopropyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl); pentyl and isomers thereof. For example, "C 1-4 "Alkyl" includes all straight or branched chain alkyl groups having 1 to 4 carbon atoms, and thus includes methyl, ethyl, n-propyl, isopropyl, butyl and isomers thereof (e.g., n-butyl, isobutyl and tert-butyl). For example, "C 1-3 "Alkyl" includes all straight or branched chain alkyl groups having 1 to 3 carbon atoms, and thus includes methyl, ethyl, n-propyl, isopropyl.

[0087] When the term "alkyl" is used as a suffix after another term, such as in "hydroxyalkyl", this is intended to mean that the alkyl group as defined above is substituted with one or two (preferably one) substituents selected from another specifically named group, also as defined herein. Thus, the term "hydroxyalkyl" refers to -R a -OH group, where R a is alkylene as defined herein.

[0088] The term "haloalkyl", as a group or part of a group, refers to an alkyl group having the meaning as defined above, wherein one or more hydrogen atoms are each substituted by a halogen as defined herein. Non-limiting examples of such haloalkyl groups include chloromethyl, 1-bromoethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1,1,1-trifluoroethyl, trichloromethyl, tribromomethyl, etc.

[0089] The term "cycloalkyl", as a group or part of a group, refers to a cyclic alkyl group, i.e., a monovalent saturated hydrocarbon group having one or more ring structures, and containing 3 to 12 carbon atoms, more preferably 3 to 9 carbon atoms, more preferably 3 to 7 carbon atoms; more preferably 3 to 6 carbon atoms. Cycloalkyl includes all saturated hydrocarbon groups containing one or more rings, including monocyclic or bicyclic groups. The additional rings of polycyclic cycloalkyls may be fused, bridged and / or joined by one or more spiro atoms. When a subscript is used after a carbon atom in this article, the subscript refers to the number of carbon atoms that the named group may contain. For example, the term "C 3-8 "Cycloalkyl" refers to a cyclic alkyl group containing 3 to 8 carbon atoms. For example, the term "C 3-6 "Cycloalkyl" refers to a cyclic alkyl group containing 3 to 6 carbon atoms. 3-12 Examples of cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, bicyclo[2.2.1]hept-2-yl, (1S,4R)-norborn-2-yl, (1R,4R)-norborn-2-yl, (1S,4S)-norborn-2-yl, (1R,4S)-norborn-2-yl, and 1-adamantyl.

[0090] The term "halocycloalkyl", as a group or part of a group, refers to a cycloalkyl group having the meaning defined above wherein one or more hydrogen atoms are each replaced by a halogen as defined herein.

[0091] The term "alkenyl", as a group or part of a group, refers to an unsaturated hydrocarbon group, which may be straight chain or branched, containing one or more carbon-carbon double bonds. When a subscript is used after a carbon atom in this document, the subscript refers to the number of carbon atoms that the named group may contain. For example, the term "C 2-6 "Alkenyl" refers to an unsaturated hydrocarbon group which may be straight chain or branched, contain one or more carbon-carbon double bonds and contain 2 to 6 carbon atoms. For example, C 2-4 Alkenyl includes all straight-chain or branched alkenyl groups having 2 to 4 carbon atoms. 2-6 Examples of alkenyl groups are ethenyl, 2-propenyl, 2-butenyl, 3-butenyl, 2-pentenyl and isomers thereof, 2-hexenyl and isomers thereof, 2,4-pentadienyl and the like.

[0092] The term "haloalkenyl", as a group or part of a group, refers to an alkenyl group having the meaning defined above wherein one or more hydrogen atoms are each replaced by a halogen as defined herein.

[0093] The compounds of the present invention may also exist in unsolvated and solvated forms. The term "solvate" is used herein to describe a molecular complex comprising a compound of the present invention and one or more pharmaceutically acceptable solvent molecules (e.g., ethanol). When the solvent is water, the term "hydrate" is used.

[0094] The currently accepted classification system for organic hydrates is one that defines isolated site, channel or metal ion coordinated hydrates - see KR Morris, "Polymorphism in Pharmaceutical Solids" (Ed. HG Brother, Marcel Dekker, 1995), which is incorporated herein by reference. Isolated site hydrates are hydrates in which the water molecules are separated from direct contact with each other by the intervening organic molecules. In channel hydrates, the water molecules are located in the channels of the crystal lattice where they are adjacent to other water molecules. In metal ion coordinated hydrates, the water molecules are bonded to the metal ion.

[0095] When the solvent or water is tightly bound, the complex will have a well-defined stoichiometry, independent of the moisture content. However, when the solvent or water is weakly bound, as in channel solvates and hygroscopic compounds, the water / solvent content will depend on the moisture content and drying conditions. In such cases, non-stoichiometry will be the norm.

[0096] As used herein and unless otherwise indicated, the term "stereoisomer" refers to all possible different isomers and conformational forms that a compound of the structural formula herein may have, in particular all possible stereochemical and conformational isomeric forms, all diastereomers, enantiomers and / or conformations of the basic molecular structure. Some compounds of the present invention may exist in different tautomeric forms, all of which are included within the scope of the present invention.

[0097] The present invention includes all possible stereoisomer compounds of formula (I) and any subgroups thereof. When the desired compound is a single enantiomer, it can be obtained by stereospecific synthesis, by splitting the final product or any convenient intermediate or by chiral chromatography, each of which is known in the art. The splitting of the final product, intermediate or starting material can be achieved by any suitable method known in the art. See, for example, "Stereochemistry of Organic Compounds" (Wiley-Interscience, 1994) by ELEil, SH Wilen and LN Mander, which is incorporated herein by reference for stereochemistry. Structural isomers are such isomer types, in which molecules with the same molecular formula have different bonding patterns and atomic organizations. When structural isomers can be mutually converted via low energy barriers, tautomerism ("tautomerism") can occur. This can take the form of proton tautomerism in compounds of the present invention containing, for example, imino, keto or oxime groups, or take the form of so-called valence tautomerism in compounds containing aromatic moieties.

[0098] The compounds of the present invention may be in the form of salts, preferably pharmaceutically acceptable salts, as generally described below. Some preferred but non-limiting examples of suitable pharmaceutically acceptable organic and / or inorganic acids are hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, acetic acid and citric acid, as well as other pharmaceutically acceptable acids known per se (for which reference is made to the prior art mentioned below).

[0099] When the compounds of the present invention contain acidic groups and basic groups, the compounds of the present invention may also form internal salts, and such compounds are within the scope of the present invention. When the compounds of the present invention contain hydrogen-donating heteroatoms (e.g., NH), the present invention also encompasses salts and / or isomers formed by transferring the hydrogen atom to a basic group or atom within the molecule.

[0100] Pharmaceutically acceptable salts of the compounds of formula (I) and any subgroups thereof include acid addition salts and base salts thereof. Suitable acid addition salts are formed from acids which form non-toxic salts. Examples include acetate, adipate, aspartate, benzoate, benzenesulfonate, bicarbonate / carbonate, bisulfate / sulfate, borate, camphorsulfonate, citrate, cyclamate, edisylate, ethanesulfonate, formate, fumarate, glucoheptonate, gluconate, glucuronate, hexafluorophosphate, hibenzate, hydrochloride / chloride, hydrobromide / bromide, hydroiodide / iodide, isethionate, lactate, malate, maleate, malonate, methanesulfonate, methylsulfate, naphthoate, 2-naphthalenesulfonate, nicotinate, nitrate, orotate, oxalate, palmitate, pamoate, phosphate / hydrogenphosphate / dihydrogenphosphate, pyroglutamate, saccharate, stearate, succinate, tannate, tartrate, toluenesulfonate, trifluoroacetate, and xinofoate. Suitable basic salts are formed from bases that form non-toxic salts. Examples include aluminum, arginine, benzathine, calcium, choline, diethylamine, diethanolamine, glycine, lysine, magnesium, meglumine, ethanolamine, potassium, sodium, tromethamine, and zinc salts. Hemisalts of acids and bases may also be formed, such as hemisulphates and hemicalcium salts. For a review of suitable salts, see Stahl and Wermuth, "Handbook of Pharmaceutical Salts: Properties, Selection, and Use" (Wiley-VCH, 2002), which is incorporated herein by reference.

[0101] The compounds of the present invention can exist in a continuous solid state from completely amorphous to completely crystalline. The term "amorphous" refers to a state in which the material lacks long-range order at the molecular level and can exhibit the physical properties of a solid or a liquid depending on the temperature. Typically, such materials do not give a distinctive X-ray diffraction pattern and, although they exhibit the properties of a solid, are more formally described as a liquid. Upon heating, a change in properties from solid to liquid occurs, characterized by a change in state, typically secondary ("glass transition"). The term "crystalline" refers to a solid phase in which the material has a regular, ordered internal structure at the molecular level and gives a distinctive X-ray diffraction pattern with well-defined peaks. Such a material will also exhibit the properties of a liquid when fully heated, but the change from solid to liquid is characterized by a phase transition, typically primary ("melting point").

[0102] Pharmaceutically acceptable salts of compounds of formula (I) may be prepared by one or more of these methods:

[0103] (i) by reacting a compound of formula (I) with a desired acid;

[0104] (ii) by reacting a compound of formula (I) with a desired base;

[0105] (iii) by removing an acid-labile or base-labile protecting group from a suitable precursor of the compound of formula (I), or by ring-opening a suitable cyclic precursor (e.g. a lactone or lactam) using the required acid; or

[0106] (iv) by converting one salt of a compound of formula (I) into another salt via reaction with an appropriate acid or with the aid of a suitable ion exchange column.

[0107] Typically, all of these reactions are carried out in solution. The salt may precipitate from the solution and be collected by filtration, or may be recovered by evaporation of the solvent. The degree of ionization of the salt may vary from fully ionized to almost non-ionized.

[0108] Additionally, although pharmaceutically acceptable salts are generally preferred with respect to salts of the compounds of the invention, it should be noted that the invention in its broadest sense also includes non-pharmaceutically acceptable salts, which may be useful, for example, in the isolation and / or purification of the compounds of the invention.

[0109] In some embodiments, cyclocidofovir for use according to the present invention has the structure of formula (I) as defined herein,

[0110] in,

[0111] A is selected from the group consisting of O and NH;

[0112] L chooses from -(CR 2 R 3 ) n -、-CH(R 4 )-C(O)- and -C(O)-CH(R 5 )-; preferably L is -(CR 2 R 3 ) n -or-CH(R 4 )-C(O)-;

[0113] n is an integer selected from 1, 2, 3, 4 or 5; preferably n is 1, 2, 3 or 4; preferably n is 1, 2 or 3;

[0114] R 1 Choose from C 6-25 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-25 Haloalkyl, C 6-25Alkenyl, C 6-25 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 The group consisting of halogenated cycloalkyl; preferably R 1 It is C 6-24 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-24 Haloalkyl, C 6-25 Alkenyl, C 6-24 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 Preferably R 1 It is C 6-24 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-24 Haloalkyl, C 6-24 Alkenyl, C 6-24 Halogenated alkenyl, C 3-10 Cycloalkyl and C 3-10 Preferably R 1 It is C 6-23 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-23 Haloalkyl, C 6-23 Alkenyl, C 6-23 Halogenated alkenyl, C 3-10 Cycloalkyl and C 3-10 Preferably R 1 It is C 6-22 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-22 Haloalkyl, C 6-22 Alkenyl, C 6-22 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 Preferably R 1 It is C 6-21 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-21 Haloalkyl, C 6-21 Alkenyl, C 6-21 Halogenated alkenyl, C 3-10 Cycloalkyl and C 3-10 Preferably R 1 It is C 6-20 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-20 Haloalkyl, C6-20 Alkenyl, C 6-20 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 Preferably R 1 It is C 6-20 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-20 Haloalkyl, C 6-20 Alkenyl, C 6-20 Halogenated alkenyl, C 3-10 Cycloalkyl and C 3-10 Preferably R 1 It is C 6-20 Alkyl, -C(O)R 6 、-CO2R 7 , C 6-20 Haloalkyl, C 3-12 Cycloalkyl and C 3-12 Preferably R 1 It is C 6-20 Alkyl, -C(O)R 6 and -CO2R 7 Preferably R 1 It is C 6-18 Alkyl, -C(O)R 6 and -CO2R 7 ;

[0115] Each R 2 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; preferably each R 2 are independently hydrogen, C 1-6 Alkyl, C 3-10 Cycloalkyl and halogen; preferably each R 2 are independently hydrogen, C 1-6 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 2 are independently hydrogen, C 1-5 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 2 are independently hydrogen, C 1-5 Alkyl, C 3-8 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 2 independently hydrogen and C 1-5 alkyl;

[0116] Each R 3 independently selected from hydrogen, C 1-6 Alkyl, C 3-12The group consisting of cycloalkyl and halogen; preferably each R 3 are independently hydrogen, C 1-6 Alkyl, C 3-10 Cycloalkyl and halogen; preferably each R 3 are independently hydrogen, C 1-6 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 3 are independently hydrogen, C 1-5 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 3 are independently hydrogen, C 1-5 Alkyl, C 3-8 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 3 independently hydrogen and C 1-5 alkyl;

[0117] Each R 4 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; preferably each R 4 are independently hydrogen, C 1-6 Alkyl, C 3-10 Cycloalkyl and halogen; preferably each R 4 are independently hydrogen, C 1-6 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 4 are independently hydrogen, C 1-5 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 4 are independently hydrogen, C 1-5 Alkyl, C 3-8 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 4 are independently hydrogen, C 1-4 Alkyl and C 3-8 Cycloalkyl; preferably each R 4 independently hydrogen and C 1-5 alkyl;

[0118] Each R 5 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; preferably each R 5 are independently hydrogen, C 1-6 Alkyl, C 3-10 Cycloalkyl and halogen; preferably each R 5 are independently hydrogen, C 1-6 Alkyl, C 3-10cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 5 are independently hydrogen, C 1-5 Alkyl, C 3-10 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 5 are independently hydrogen, C 1-5 Alkyl, C 3-8 cycloalkyl, fluorine, chlorine, iodine and bromine; preferably each R 5 independently hydrogen and C 1-5 alkyl;

[0119] Each R 6 Independently selected from C 1-10 Alkyl, C 1-10 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 The group consisting of haloalkenyl; preferably each R 6 Independently C 1-8 Alkyl, C 1-8 Haloalkyl, C 3-10 Cycloalkyl, C 3-10 Halogenated cycloalkyl, C 2-8 Alkenyl and C 2-8 haloalkenyl; preferably each R 6 Independently C 1-6 Alkyl, C 1-6 Haloalkyl, C 3-8 Cycloalkyl, C 3-8 Halogenated cycloalkyl, C 2-6 Alkenyl and C 2-6 haloalkenyl; preferably each R 6 Independently C 1-6 Alkyl, C 1-6 Haloalkyl, C 2-6 Alkenyl and C 2-6 haloalkenyl;

[0120] Each R 7 Independently selected from C 1-10 Alkyl, C 1-12 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 The group consisting of haloalkenyl; preferably each R 7 Independently C 1-8 Alkyl, C 1-8 Haloalkyl, C 3-10 Cycloalkyl, C 3-10 Halogenated cycloalkyl, C 2-8 Alkenyl and C 2-8haloalkenyl; preferably each R 7 Independently C 1-6 Alkyl, C 1-6 Haloalkyl, C 3-8 Cycloalkyl, C 3-8 Halogenated cycloalkyl, C 2-6 Alkenyl and C 2-6 haloalkenyl; preferably each R 7 Independently C 1-6 Alkyl, C 1-6 Haloalkyl, C 2-6 Alkenyl and C 2-6 haloalkenyl;

[0121] or stereoisomers, tautomers, solvates, hydrates, or pharmaceutically acceptable salts thereof.

[0122] In some embodiments, A is O. In some embodiments, L is -(CR 2 R 3 ) n -. In some embodiments, L is -CH(R 4 )-.

[0123] Particularly preferred compounds of the invention are those listed in the following table.

[0124]

[0125]

[0126] The term "treat" or "treatment" encompasses both therapeutic treatment of an established disease or condition, such as treatment of an established ASFV infection, and prophylactic or preventive measures, wherein the goal is to prevent or reduce the likelihood of undesirable suffering, such as preventing the onset, development and progression of an ASFV infection. Beneficial or desired clinical outcomes may include, but are not limited to, alleviation of one or more symptoms or one or more biomarkers, reduction in the extent of the disease, stabilization of the disease state (i.e., no worsening), delay or slowing of disease progression, improvement or alleviation of the disease state, and the like. "Treatment" may also mean prolonging survival compared to the expected survival without treatment. "Treatment" may also mean reducing the viral load of ASFV in an animal, thereby reducing infectivity in the animal and / or reducing viral shedding, thereby reducing transmission / spread of the virus / disease.

[0127] Unless otherwise indicated, the terms "animal", "subject" or "patient" may be used interchangeably and refer to an animal, preferably a warm-blooded animal, more preferably a vertebrate, even more preferably a mammal, still more preferably a member of the family Suidae, still more preferably a member of the genus Sus. Preferred subjects are wild or domesticated pigs or swines. More preferred subjects are domestic pigs (Sus domesticus). Non-limiting examples of members of the Suidae family include Golden babirusa, Sulawesi babirusa, Togian babirusa, Giant forest hog, Desert warthog, common warthog, pygmy hog, bushpig, redriver hog, Palawan bearded pig, bearded pig, Vietnamese warty pig, Visayan warty pig, Celebes warty pig, Flores warty pig, Mindoro warty pig, Philippine warty, Javan warty pig, wild boar, and domestic pig.

[0128] The term "subject" or "patient" includes a subject in need of treatment, more particularly a subject who would benefit from treatment of a given condition, particularly an ASFV infection. Such subjects may include, but are not limited to, those subjects who have been diagnosed with the condition, those subjects who are susceptible to developing the condition, and / or those subjects in whom the condition is to be prevented.

[0129] In particular embodiments, the animal is a member of the Suidae family, a member of the genus Sus, preferably a domestic pig, a wild pig, a domestic swine, or a wild swine (ie, a wild boar).

[0130] As used herein, the term "African swine fever" or "ASF" refers to a viral disease caused by ASFV infection. ASFV is a large enveloped double-stranded DNA virus. Its genome contains 170,000 to 193,000 base pairs together with up to 167 open reading frames. ASFV is the only member of the African swine fever virus family (family Asfarviridae), and is the only known DNA spread by the soft ticks of arthropods, i.e., the genus Ornithodoros. According to the sequence variation in the C-terminal region of the B646L gene encoding the major capsid protein p72, 24 ASFV genotypes (I-XXIV) have been identified at present. ASF can be any type of ASF, including the ASF caused by any ASFV genotype or ASFV isolate (such as Georgia (Georgia) 2007 / 1 isolate, KAB6 / 2 isolate, BOT1 / 99 isolate and Magadi (Magadi) w / hog 9 isolate).

[0131] In particular embodiments, ciclocidofovir or a prodrug thereof allows for the treatment of pan-genotypic ASFV.

[0132] In a particular embodiment, ciclocidofovir or a prodrug thereof is orally administered in the form of a powder, liquid, semi-liquid, pill, tablet, capsule or granule.

[0133] Administering a dose of cyclocidofovir or a prodrug thereof to an animal daily may refer to administering a full dose of cyclocidofovir or a prodrug thereof at a given time of the day (i.e. once a day). Administering a dose of cyclocidofovir or a prodrug thereof to an animal daily also encompasses dispersing the dose of cyclocidofovir or a prodrug thereof at multiple given times of the day or over a long period of time in the day, such as by continuous administration, for example by allowing free access to water and / or feed containing an adjusted dose.

[0134] If two doses of cyclocidofovir or a prodrug thereof are administered daily to an animal (wherein the daily dose of cyclocidofovir or a prodrug thereof is twice the daily dose used to administer one dose of cyclocidofovir or a prodrug thereof), each of the two doses can be administered to the animal at a given time of day (e.g., twice daily as described elsewhere herein), or the administration of each dose can be spread out over multiple given times of day or over a long period of time during the day, such as by continuous administration or ad libitum administration.

[0135] In a particular embodiment, ciclocidofovir or a prodrug thereof is administered orally by mixing ciclocidofovir or a prodrug thereof with the animal's feed or drinking water.

[0136] In a particular embodiment, cyclocidofovir or a prodrug thereof is administered to an animal at a dose of 10.0 to 30.0 mg cyclocidofovir or a prodrug thereof / kg animal body weight (mg / kg), 15.0 to 30.0 mg / kg of the cyclocidofovir or a prodrug thereof, 20.0 to 30.0 mg / kg of the cyclocidofovir or a prodrug thereof, or 25.0 to 30.0 mg / kg of the cyclocidofovir or a prodrug thereof, preferably about 30.0 mg / kg of the cyclocidofovir or a prodrug thereof.

[0137] On a daily basis, one or two such doses of cyclocidofovir or its prodrug can be administered to an animal. In a particular embodiment, if an animal is administered one dose of cyclocidofovir or its prodrug daily, the total daily dose or total amount of cyclocidofovir or its prodrug is 10.0 to 30.0 mg cyclocidofovir or its prodrug / kg animal body weight (mg / kg), 15.0 to 30.0 mg / kg of the cyclocidofovir or its prodrug, 20.0 to 30.0 mg / kg of the cyclocidofovir or its prodrug, or 25.0 to 30.0 mg / kg of the cyclocidofovir or its prodrug, preferably about 30.0 mg / kg of the cyclocidofovir or its prodrug. In a particular embodiment, if two doses of cyclocidofovir or a prodrug thereof are administered to an animal daily, the total daily dose of cyclocidofovir or a prodrug thereof is 20.0 to 60.0 mg cyclocidofovir or a prodrug thereof / kg animal body weight (mg / kg), 30.0 to 60.0 mg / kg of the cyclocidofovir or a prodrug thereof, 40.0 to 60.0 mg / kg of the cyclocidofovir or a prodrug thereof, or 50.0 to 60.0 mg / kg of the cyclocidofovir or a prodrug thereof, preferably about 60.0 mg / kg of the cyclocidofovir or a prodrug thereof. Similarly, if three or more doses are administered, this will correspond to a total dose of three or more times the following dose: 10.0 to 30.0 mg cyclocidofovir or its prodrug / kg animal body weight (mg / kg), 15.0 to 30.0 mg / kg of said cyclocidofovir or its prodrug, 20.0 to 30.0 mg / kg of said cyclocidofovir or its prodrug, or 25.0 to 30.0 mg / kg of said cyclocidofovir or its prodrug, preferably about 30.0 mg / kg of said cyclocidofovir or its prodrug.

[0138] In a particular embodiment, at least one dose of cyclocidofovir or its prodrug (such as one or two doses) is administered to the animal daily in a first time period of 1 to 4 consecutive days (i.e., during), and a dose of cyclocidofovir is administered to the animal every other day or every day in a second time period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5 consecutive days. Therefore, in a particular embodiment, a total daily dose of 10.0 to 60.0 mg / kg of cyclocidofovir or its prodrug is administered to the animal daily in a first time period of 1 to 4 consecutive days, and a total daily dose of 10.0 to 30.0 mg / kg of cyclocidofovir or its prodrug is administered to the animal every other day or every day in a second time period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5 consecutive days.

[0139] In a particular embodiment, the second administration period immediately follows the first administration period, meaning that the first administration period and the second administration period are not separated by a third period of time during which cilcidofovir or a prodrug thereof is or is not administered.

[0140] In particular embodiments, the administration comprises a first period of 1 to 4 consecutive days, such as 1, 2, 3 or 4 consecutive days, preferably 3 consecutive days, wherein the animal is administered two doses of ciclocidofovir or a prodrug thereof daily.

[0141] In particular embodiments, the administration comprises a first period of 1 to 4 consecutive days, such as 1, 2, 3 or 4 consecutive days, preferably 3 consecutive days, wherein the animal is administered a dose of ciclocidofovir or a prodrug thereof daily.

[0142] In particular embodiments, the administration comprises a second period of 5 to 14 consecutive days, such as 5 to 13 consecutive days, 5 to 12 consecutive days, 5 to 10 consecutive days, 5 to 8 consecutive days, 5 to 7 consecutive days, preferably 5 days, wherein the animal is administered a dose of cyclocidofovir or a prodrug thereof daily.

[0143] In a particular embodiment, the administration comprises a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5, 6 or 7 consecutive days, more preferably 5 consecutive days or preferably 10 to 14 consecutive days, such as 10, 11, 12, 13 or 14 consecutive days, more preferably 13 consecutive days, wherein the animal is administered a dose of cyclocidofovir or a prodrug thereof every other day.

[0144] In a particular embodiment, the animal is administered a dose of ciclocidofovir every other day or daily for a second period of 5 to 7 consecutive days, preferably 5 consecutive days.

[0145] In a particular embodiment, the second period of time wherein ciclocidofovir or a prodrug thereof is administered every other day begins on the day of administration (treatment).

[0146] In a particular embodiment, the administration comprises a first period of 3 consecutive days, wherein the animal is administered two doses of cyclocidofovir or a prodrug thereof daily, and a second period of 5 to 14 consecutive days, such as 5 to 12 consecutive days, 5 to 10 consecutive days, 5 to 8 consecutive days, 5 to 7 consecutive days, preferably 5 consecutive days, wherein the animal is administered one dose of cyclocidofovir or a prodrug thereof daily.

[0147] In a particular embodiment, the animal is administered a dose of the cyclocidofovir or a prodrug thereof daily for a first period of 3 consecutive days, and the animal is administered a dose of the cyclocidofovir or a prodrug thereof every other day for a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5, 6 or 7 consecutive days, more preferably 5 consecutive days or preferably 10 to 14 consecutive days, such as 10, 11, 12, 13 or 14 consecutive days, more preferably 13 consecutive days.

[0148] The inventors have discovered that a dosage regimen comprising a first period of time in which two doses of cyclocidofovir or a prodrug thereof are administered to the animal daily and a second period of time in which one dose of cyclocidofovir or a prodrug thereof is administered to the animal daily (as described elsewhere herein) is preferred over a dosage regimen comprising administering one dose of cyclocidofovir or a prodrug thereof to the animal daily in a first period of time and administering one dose of said cyclocidofovir or a prodrug thereof to the animal every other day in a second period of time (as described elsewhere herein).

[0149] As described elsewhere herein, the dose of ciclocidofovir or a prodrug thereof may be administered to the animal all at one given moment in time.

[0150] Thus, in a particular embodiment, administration comprises a first period of 1 to 4 consecutive days, such as 1, 2, 3 or 4 consecutive days, preferably 3 consecutive days, wherein the animal is administered two doses of cyclocidofovir or a prodrug thereof daily, and wherein each of said doses of cyclocidofovir or a prodrug thereof is administered to the animal in full at a given moment in time. In such an embodiment, the animal will receive one administration of a dose of cyclocidofovir or a prodrug thereof twice daily, resulting in a total of two doses per day.

[0151] If the animal receives two doses daily, each dose of 10.0 to 30.0 mg / kg ciclocidofovir or a prodrug thereof is preferably the same.

[0152] In a particular embodiment, the administration comprises a first period of 1 to 4 consecutive days, such as 1, 2, 3 or 4 consecutive days, preferably 3 consecutive days, wherein a dose of cyclocidofovir or a prodrug thereof is administered to the animal once daily. Thus, in such an embodiment, the animal receives a full dose of cyclocidofovir or a prodrug thereof at a given time in a day.

[0153] In a particular embodiment, the administration comprises a second period of 5 to 14 consecutive days, such as 5 to 12 consecutive days, 5 to 10 consecutive days, 5 to 8 consecutive days, 5 to 7 consecutive days, preferably five days, wherein the animal is administered a dose of cyclocidofovir or a prodrug thereof once daily. Thus, in such an embodiment, the animal receives a full dose of cyclocidofovir or a prodrug thereof at a given time in a day.

[0154] In a particular embodiment, the administration comprises a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5, 6 or 7 consecutive days, more preferably 5 consecutive days or preferably 10 to 14 consecutive days, such as 10, 11, 12, 13 or 14 consecutive days, more preferably 13 consecutive days, wherein the animal is administered a dose of cyclocidofovir or a prodrug thereof every other day. Thus, in such an embodiment, the animal receives a full dose of cyclocidofovir or a prodrug thereof at a given time in a day.

[0155] In a particular embodiment, the second period of time wherein cilcidofovir or a prodrug thereof is administered every other day begins on the treatment day.

[0156] In a particular embodiment, the administration comprises a first period of 3 consecutive days, wherein the animal is administered each of the two doses of cyclocidofovir or its prodrug once daily (i.e., the animal receives a dose of cyclocidofovir or its prodrug twice daily), and a second period of 5 to 14 consecutive days, such as 5 to 12 consecutive days, 5 to 10 consecutive days, 5 to 8 consecutive days, 5 to 7 consecutive days, preferably 5 consecutive days, wherein the animal is administered a dose of cyclocidofovir or its prodrug once daily.

[0157] In a particular embodiment, the animal is administered a dose of cyclocidofovir or a prodrug thereof once daily for a first period of 3 consecutive days, and the animal is administered a dose of cyclocidofovir or a prodrug thereof once every other day for a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days, such as 5, 6 or 7 consecutive days, more preferably 5 consecutive days, or preferably 10 to 14 consecutive days, such as 10, 11, 12, 13 or 14 consecutive days, more preferably 13 consecutive days.

[0158] In a particular embodiment, if the administration is performed daily, the dose of cyclocidofovir or its prodrug is preferably administered with 20 to 28 hours, preferably 22 to 26 hours, more preferably 24 hours between the two administrations. In a specific embodiment, if the administration is performed daily, the dose of cyclocidofovir or its prodrug is preferably administered at approximately the same hour daily.

[0159] In particular embodiments, administration of ciclocidofovir or a prodrug thereof coincides with one or more feeding times of the animal.

[0160] In a particular embodiment, if the administration is performed every other day, the dose of cyclocidofovir or its prodrug is preferably administered with 44 to 52 hours, preferably 46 to 50 hours, more preferably 48 hours between the two administrations. In a particular embodiment, if the administration is performed every other day, the dose of cyclocidofovir or its prodrug is preferably administered at approximately the same hour every other day.

[0161] In a particular embodiment, if the animal receives two doses of cyclocidofovir or a prodrug thereof daily, cyclocidofovir or a prodrug thereof is preferably administered with 8 to 16 hours, preferably 10 to 14 hours, more preferably 12 hours between administration of each of the two doses.

[0162] In a particular embodiment, cyclocidofovir or a prodrug thereof is administered to an animal when the animal is infected with ASFV or when an ASFV infection is to be prevented in said animal.

[0163] In a particular embodiment, cyclocidofovir or a prodrug thereof is administered to an animal once it is diagnosed with ASF, wherein the animal diagnosed with ASF is housed on the same farm as the animal to be treated or in an area with a radius of 3 km to 10 km around the housing of the animal to be treated.

[0164] After animals are infected with ASF, different zones and areas can be designated around the infected area (i.e., the area directly surrounding the infected site or infected animals) to control and monitor the outbreak. There may be an ASF buffer zone around the infected area. There may be an ASF monitoring zone around the buffer zone. However, different competent authorities may use different terms to refer to the zone. For example, the infected area may also be referred to as an isolation zone. In addition, the buffer zone and / or monitoring zone may be a protected area, i.e., an area where specific biosafety and sanitary measures are implemented to prevent ASFV from entering a free country or region from a neighboring country or region with a different sanitary status.

[0165] In a particular embodiment, the animals are placed in an ASF infected area, buffer zone, monitoring zone, protected area or quarantine zone. The requirements for ASF infected areas, buffer zones, monitoring zones, protected areas or quarantine zones may be specified by national authorities or the World Organization for Animal Health (OIE). Preferably, the width of the zone closest to the infected place or infected animal is a 3km to 20km radius around the infected place or infected animal. In a particular embodiment, the zone typically has a perimeter of at least 3km around the perimeter of the nearest infected place or infected animal.

[0166] The inventors have found that cyclocidofovir or a prodrug thereof can be used to reduce viremia and viral shedding in exposed pigs, and to preventively treat healthy pigs in outbreak infected areas. Therefore, in a particular embodiment, the administration of cyclocidofovir or a prodrug thereof prevents the spread of ASF in animal populations, such as in subsequent ASF buffer zones, monitoring zones and / or protective isolation zones.

[0167] The compounds of the present invention may be used in combination with other therapeutic agents to treat or prevent the above-mentioned infections or conditions.

[0168] In a particular embodiment, cyclocidofovir or a prodrug thereof is contained in a pharmaceutical composition. The pharmaceutical composition may include a pharmaceutically acceptable carrier. Such a pharmaceutical preparation or composition may be contained in a kit of parts.

[0169] As used herein, the term "pharmaceutically acceptable" is consistent with the art and means compatible with the other ingredients of a pharmaceutical composition and not deleterious to the recipient thereof.

[0170] As used herein, "carrier" or "excipient" includes any and all solvents, diluents, buffers (such as, for example, neutral buffered saline or phosphate buffered saline), solubilizers, colloids, dispersion media, vehicles, fillers, chelating agents (such as, for example, EDTA or glutathione), amino acids (such as, for example, glycine), proteins, disintegrants, binders, lubricants, wetting agents, emulsifiers, sweeteners, colorants, flavoring agents, fragrances, thickeners, agents for achieving a reservoir effect, coatings, antifungal agents, preservatives, antioxidants, tonicity control agents, absorption delaying agents, etc. The use of such media and agents in pharmaceutically active substances is well known in the art. Unless any conventional media or agents are incompatible with the active substance, their use in therapeutic compositions may be considered.

[0171] For example, for oral administration, the pharmaceutical composition can be formulated into powders, pills, tablets, enameled tablets, coated (e.g., sugar-coated) tablets, granules, hard and soft gelatin capsules, aqueous solutions, alcoholic solutions or oily solutions, syrups, emulsions or suspensions. In one example (but not limited thereto), the preparation of the oral dosage form can be suitably accomplished by uniformly and intimately blending an appropriate amount of cyclocidofovir or a prodrug thereof as disclosed herein in powder form (optionally also including one or more solid carriers that are subdivided), and formulating the blend into pills, tablets or capsules. Exemplary but non-limiting solid carriers include calcium phosphate, magnesium stearate, talc, sugars (such as, for example, glucose, mannose, lactose or sucrose), sugar alcohols (such as, for example, mannitol), dextrins, starches, gelatin, cellulose, polyvinylpyrrolidine, low melting waxes and ion exchange resins. Compressed tablets containing the pharmaceutical composition can be prepared in the following manner: cyclocidofovir or its prodrug as disclosed herein is uniformly and intimately mixed with a solid carrier such as described above to provide a mixture having the necessary compression properties, and then the mixture is pressed into the desired shape and size in a suitable machine. Molded tablets can be made by molding a mixture of powdered compounds moistened with an inert liquid diluent in a suitable machine. Suitable carriers for soft gelatin capsules and suppositories are, for example, fats, waxes, semisolid and liquid polyols, natural or hardened oils, etc.

[0172] In a particular embodiment, ciclocidofovir or a prodrug thereof is contained in a pharmaceutical composition, preferably wherein the pharmaceutical composition is an aqueous solution.

[0173] In a particular embodiment, the pH of the pharmaceutical composition is between 6.0 and 8.0. The pH can be neutralized by any method known in the art, such as by including NaHCO3.

[0174] In a particular embodiment, the pharmaceutical composition is an aqueous solution comprising 5 to 40 mg / ml, preferably 10 to 30 mg / ml, such as about 20 mg / ml of ciclocidofovir or a prodrug thereof.

[0175] Another aspect provides an aqueous solution comprising water and cyclocidofovir or a prodrug thereof. It will be appreciated by those skilled in the art that the concentration of cyclocidofovir or a prodrug in the aqueous solution may be adjusted according to the type of animal, the age of the animal and / or the type of animal farm (e.g., breeding / nursery facilities, weaning farms, fattening farms), as long as the final daily dose of cyclocidofovir or a prodrug consumed by the animal is as described elsewhere herein.

[0176] Another aspect provides a feed composition comprising feed and cyclocidofovir or a prodrug thereof. It will be understood by those skilled in the art that the concentration of cyclocidofovir or a prodrug in the feed can be adjusted according to the type of animal, the age of the animal and / or the type of animal farm (e.g., breeding / nursery facilities, weaning farms, fattening farms), as long as the final daily dose of cyclocidofovir or a prodrug consumed by the animal is as described elsewhere herein.

[0177] In particular embodiments, the pharmaceutical compositions, aqueous solutions or feed compositions provided herein comprise an ester, an amidate or an esteramidate of a compound of formula (i):

[0178]

[0179]

[0180] In further particular embodiments, the pharmaceutical composition, feed composition or water composition comprises an acyloxyalkyl ester, an alkoxycarbonyloxyalkyl ester, an alkoxyalkyl ester or a phosphoamidate or phosphoamidate thereof.

[0181] In particular embodiments, the above-mentioned composition comprises one or more compounds selected from the group consisting of:

[0182]

[0183] In another particular embodiment, the compound is selected from the group consisting of compounds 2, 3, 4 and 5 above. The above compositions are found to be particularly useful for treating animals, most particularly for treating viremia in animals. In particular, these compositions are found to be useful for treating African swine fever (ASF) in animals.

[0184] The following examples are intended to illustrate the invention and should not be construed as limiting its scope. Example

[0185] Example 1. Synthesis of cHPMPC

[0186]

[0187] At 25 ± 5 ° C, to (S) -2- (4-amino -2- oxo -2H- pyrimidine -1- base) -1- hydroxymethyl -ethoxymethyl] -phosphonic acid (140g, 0.5mol, 1.0 equivalents) in dimethylformamide (140mL, 10V) in a solution of N, N '- dicyclohexyl -4- morpholine formamidine (162g, 1.1 equivalents) and N, N- dicyclohexyl carbodiimide (311g, 3.0 equivalents). The resulting reaction mass is heated to 90 ± 5 ° C, and stirred at 90 ± 5 ° C for 8 hours. After completion, the reaction mass is cooled to room temperature, and the volatiles are evaporated under reduced pressure. The crude product is diluted with water (14V) and filtered. The filtrate is concentrated under reduced pressure. The crude product is dissolved in a minimum amount of water, and loaded onto a column (20w / w) in the form of DOWEX 1 * 2 acetate. Elution was performed with increasing percentages of 1.0 M acetic acid in purified water. The desired product was collected at 3 to 7% 1.0 M acetic acid in purified water. The product containing fractions were concentrated to obtain the product as an off-white solid. Yield: 93.3 g, 71%.

[0188] Example 2. In vitro antiviral activity of cHPMPC against different ASFV strains

[0189] Primary peripheral blood mononuclear cells (PBMCs) were treated with serial dilutions of cyclocidofovir and infected with Georgia 2007 / 1, KAB6 / 2, BOT 1 / 99 or Magadi w / hog9 at 0.1 MOI for 72 hours. Progeny virus shedding (%) was determined by hemositation assay. EC 50 The values ​​were calculated using nonlinear regression, and the average EC 50 From three independent experiments (with standard deviations shown).

[0190] Table 1

[0191]

[0192] Example 3. Cytotoxicity

[0193] Purified peripheral blood mononuclear cells (PBMCs) were treated with serial dilutions of cyclocidofovir for 72 hours and analyzed by RealTime-Glo TM Cell viability was measured using the MT cell viability assay or the CellTiter 96 non-radioactive cell proliferation assay (MTT). 50 Values ​​(50% cytotoxic concentration) were calculated from relative cell viability (%) by nonlinear regression. Four independent experiments were performed in triplicate and values ​​represent mean values ​​and standard deviations.

[0194] Table 2

[0195]

[0196] Example 4. Single-dose pharmacokinetic study in pigs

[0197] Materials and methods

[0198] Test Materials

[0199] cHPMPC 20 mg / mL aqueous solution (pH neutralized with NaHCO3), also referred to herein as "VV03-0035".

[0200] Overview of Study Design

[0201] A total of three weaned piglets (age 3 weeks and 5 days) were obtained from a commercial pig farm. The animals were examined upon arrival to confirm that they were in good health and then ear-tagged. The animals were housed on straw as a group. The animals were allowed to acclimate for 7 days before the start of the procedure.

[0202] On day 0, once determined to be suitable for inclusion in the study, all animals were weighed and bled, and then each was administered the test material by the intravenous route. After administration, blood samples were collected at 10 min (± 2 min), 30 min (± 2 min), 45 min (± 2 min), 1 h (± 2 min), 2 h (± 2 min), 4 h (± 2 min), 6 h (± 2 min), 8 h (± 2 min), 12 h (± 2 min) and 24 h (± 2 min).

[0203] After the last blood sampling, the animals were allowed to recover for seven days. On the 8th day, all animals were weighed, blood was collected, and then each was administered the test material by the oral route. After administration, blood samples were collected at 30min (±2min), 1h (±2min), 2h (±2min), 3h (±2min), 4h (±2min), 5h (±2min), 6h (±2min), 8h (±2min), 12h (±2min) and 24h (±2min).

[0204] Clinical observations included relevant injection site assessments approximately 1 hour and 4 hours after administration on Days 0 and 8.

[0205] The study was completed on Day 9. An overview of the study design is provided in Table 3 below.

[0206]

[0207] result

[0208] In this study, VV03-0035 was well tolerated in pigs. In general, pigs did not show abnormal behavior or signs of injury or illness during the study, and all pigs were considered to be in good overall health during observations conducted 1 and 4 hours after administration of VV03-0035. Redness at the injection site was observed in all pigs 1 hour after intravenous administration of VV03-0035. However, in the observations 4 hours after intravenous administration, no injection site reactions were observed. No other adverse events were recorded after intravenous administration of 5 mg / kg or oral administration of VV03-0035 orally at 25 mg / kg.

[0209] The results obtained in this study showed that after a single intravenous administration of VV03-0035 at a dose of 5 mg / kg, or after a single oral administration of VV03-0035 at a dose of 25 mg / kg, all animals, except one pig (pig #342008) at 24 hours after oral administration, showed measurable concentrations of both VV03-0035 and cidofovir in plasma until 24 hours after administration (last sampling time). This can be explained by the fact that pig #342008 did not receive the full target dose of 25 mg / kg of VV03-0035, but received an actual dose of approximately 21.7 mg / kg on the day of oral administration, which resulted in a lower dose (approximately 83100 nmol / kg) compared to the other 2 animals (doses of 93900 and 92400 nmol / kg).

[0210] The mean maximum plasma concentration (C max ) was 49504±18300nM, and the mean maximum plasma concentration (C max ) was 2036±1340 nM. The latter was reached 2 hours after oral administration. The mean C of cidofovir after intravenous administration of VV03-0035 max was 1816 ± 86 nM and reached 2 hours after administration (for all 3 pigs). maxIt is 221±140nM and is reached in 3 to 8 hours (depending on the pig). For VV03-0035, for intravenous administration, the exposure (expressed as the area under the curve or AUC) ranged from 58000 to 95400nM.h, with a mean of 71571nM.h and a %CV between subjects of 29%, while for oral administration, the exposure ranged from 2320 to 23700nM.h, with a mean of 11573nM.h and a %CV between subjects of 91%. Due to the absence of an obvious terminal elimination phase, the exposure parameters of cidofovir are less accurate. The average exposure of cidofovir after intravenous administration of VV03-0035 was 12044nM.h, and the average exposure of cidofovir after oral administration of VV03-0035 was 3562nM.h. The average half-life (t 1 / 2 ) values ​​were 3.31 hours and 3.51 hours, respectively. The average t of cidofovir after intravenous and oral administration of VV03-0035 1 / 2 The values ​​are 9.37 hours and 11.23 hours respectively.

[0211] Table 4

[0212]

[0213] Example 5. VV03-0035 Challenge Study in Pigs

[0214] Materials and methods

[0215] VV03-0035 was formulated as a 20 mg / ml aqueous solution (pH neutralized with NaHCO3).

[0216] ASFV strain Georgia 2007 / 1 is a genotype II field isolate from the 2007 Georgia ASFV outbreak and is part of the ASFV strain collection available at the Pirbright Institute where the research was conducted.

[0217] Study Design

[0218] Two groups were placed in one room, group 1 was the VV03-0035 treatment group (n = 6 pigs, 3 boars and 3 sows) and group 2 was the placebo group (n = 3, mixed sex). Pigs were assigned to treatment groups according to a randomized block design. Female piglets (n = 5) and male piglets (n = 4) were sorted from high to low by weight and assigned random numbers generated by commercially available software (Excel). Starting from the lightest pair, the animals with higher random numbers were assigned to the VV03-0035 treatment group (group 1), and the animals with lower random numbers were assigned to the control group (group 2).

[0219] Animals were allowed to acclimate for 7 days and clinical scores were performed daily, including body temperature, starting 3 days before the start of the experiment until the end of the experiment. EDTA blood (1 ml) and serum (4 ml) were collected from each pig on day -1. Nasal, oral and rectal swabs were also collected from each pig.

[0220] Next, after ASFV challenge (challenge on day 0), VV03-0035 or placebo (saline) was delivered orally twice a day (30 mg / kg, 1.5 mL / kg, 12 hours apart) for 3 days (from day -1 to day +1). From day 2 to day 6, the drug was delivered once a day at approximately the same time every morning. The pigs were kept for another 21 days to observe typical clinical symptoms of ASFV or drug treatment. The volume of VV03-0035 per pig was calculated based on daily body weight. The control pigs were given the same volume / kg of placebo.

[0221] On day 0, 30-60 minutes after administration of VV03-0035 or placebo to Group 1 and Group 2, respectively, all pigs were treated with 10 3 HAD 50 (50% blood dose) Georgia 2007 / 1 attack.

[0222] It is anticipated that the Group 2 control pigs will be culled on day 5 or 6 for humane welfare reasons.

[0223] Table 5

[0224]

[0225] ASFV DNA was measured in whole blood by quantitative qPCR using primers specific for the B646L ASFV gene encoding the VP72 protein, using the method described by King et al., "Protection of European domestic pigs from virulent African isolates of African swine fever by experimental immunization," Vaccine 29 (2011): 4593-4600 (hereinafter further referred to as "King et al. (2011)"). Results are expressed as genome copies / ml blood by comparison with a standard curve of a control plasmid.

[0226] ASFV DNA was measured in nasal, oral and rectal swabs by quantitative qPCR using primers specific for the B646LASFV gene encoding the VP72 protein, using the method described by King et al. (2011). The virus was eluted from the swab samples with phosphate-buffered saline. The results were expressed as genome copies / ml by comparison with a standard curve of a control plasmid.

[0227] result

[0228] All Group 2 control pigs (n=3) were humanely euthanized on day 6 due to reaching a humane endpoint of moderate severity due to ASF disease.

[0229] Of the 6 pigs treated with VV03-0035, 2 pigs were euthanized at a humane endpoint of moderate severity on day 6 after ASFV challenge, demonstrating reduced ASF disease, 2 pigs were euthanized at a humane endpoint of moderate severity on days 19 and 20 after ASFV challenge, with delayed and reduced ASF disease, and the remaining 2 pigs survived to the end of the study (day 27 after ASFV challenge) with no ASF disease ( Figure 1 and 2 ).

[0230] The inventors found that compared with control pigs, the blood of treated pigs ( Figure 3 ) and swab samples ( Figure 4 ) in which the ASFV genome copies were reduced.

[0231] Example 6. VV03-0035 Challenge Study in Pigs

[0232] Materials and methods

[0233] VV03-0035 was formulated as a 20 mg / ml aqueous solution (pH neutralized with NaHCO3).

[0234] ASFV strain Georgia 2007 / 1 is a genotype II field isolate from an ASFV outbreak in Georgia and is part of the ASFV strain collection available at the Pirbright Institute where the research was conducted.

[0235] Study Design

[0236] Two groups were placed in two separate rooms, group 1 was the VV03-0035 treatment group (n = 6 pigs, 3 boars and 3 sows) and group 2 was the placebo group (n = 6 pigs, 3 boars and 3 sows). Pigs were assigned to treatment groups according to a randomized block design. Female piglets (n = 6) and male piglets (n = 6) were sorted from high to low by weight and assigned random numbers generated by commercially available software (Excel). Starting with the lightest pair of the same sex, the animals with higher random numbers were assigned to the VV03-0035 treatment group (group 1), and the animals with lower random numbers were assigned to the control group (group 2).

[0237] Animals were allowed to acclimate for 7 days and clinical scores were performed daily, including body temperature, starting 3 days before the start of the experiment until the end of the experiment. EDTA blood (1 ml) and serum (4 ml) were collected from each pig on day -1. Nasal, oral and rectal swabs were also collected from each pig.

[0238] Next, VV03-0035 or placebo (saline) (30 mg / kg, 1.5 mL / kg) was delivered orally once daily on Day -1 (evening), Day 0 (30-60 minutes before ASFV challenge), Day 1 (morning), and Day 2 (morning). From Day 2 to Day 8, drug and placebo were delivered every other day (on Days 4 and 6) at approximately the same time each morning. Feed was given after administration. The volume of VV03-0035 per pig was calculated based on daily body weight. Control pigs were given the same volume / kg of placebo.

[0239] On day 0, 30-60 minutes after administration of VV03-0035 or placebo to Group 1 and Group 2, respectively, all pigs were treated with 10 3 HAD 50 (50% blood dose) Georgia 2007 / 1 attack.

[0240] It is anticipated that Group 2 control pigs will be culled on humane welfare grounds between days 4 and 6 at a moderate severity humane endpoint.

[0241] Tissue samples including spleen, lung, submandibular lymph node (SMLN), renal lymph node (RNL) and gastrohepatic lymph node (GHLN) were collected at necropsy and stored at -80°C until processing. Nucleic acid was extracted from 20 mg of homogenized tissue, and ASFV genome copies were determined by quantitative qPCR using specific primers for the B646L gene (King et al., 2011) (compared with a standard control plasmid).

[0242] At different time points before or after ASFV challenge, blood samples (in EDTA) were collected from pigs in Groups 1 and 2. ASFV genome copies / ml blood were measured by quantitative qPCR (King et al., 2011) using specific primers for the B646L ASFV gene and by comparison with a standard curve of a control plasmid.

[0243] Table 6

[0244]

[0245] result

[0246] VV03-0035 improved the survival of pigs challenged with Georgia 2007 / 1. A significant difference in median time to death was observed, with VV03-0035 treated pigs surviving until day 8, compared to a median time to death of 5.5 days for negative control animals. This difference was statistically significant as determined by the log-rank (Mantel-Cox) test and the Gehan-Breslow-Wilcoxon test, with p values ​​of 0.0010 and 0.0016, respectively ( Figure 5 ).

[0247] Compared to the placebo group, VV03-0035 significantly reduced ASF virus genome copies in multiple organs (such as lungs, spleen, and several lymph nodes) as measured by quantification of viral genomes in tissues using quantitative qPCR. Significance was calculated by nested t comparison of control and treated pigs ( Figure 6 ).

[0248] VV03-0035 significantly reduced ASF viremia as measured by quantitative qPCR. Significance was calculated by nested t comparisons of control and treated pigs within each time point ( Figure 7 ).

[0249] Example 7. Synthesis of cHMPC derivatives

[0250] Pivaloyloxymethyl ester of cHPMPC (POM-cHPMPC, compound 1)

[0251]

[0252] Tetrabutylammonium hydroxide (0.8 mL; 25% in methanol) was added dropwise to a stirred mixture of cHPMPC (200 mg; 0.766 mmol) in methanol (24 mL) under an inert atmosphere. The mixture was stirred for 10 minutes to dissolve. The solvent was then evaporated and the remaining methanol was removed with dioxane (2×6 mL). The residue was dissolved in dioxane (10 mL) and chloromethyl pivalate (0.13 mL; 1.2 eq.) was added. The mixture was stirred at 90° C. for 1 hour. The reaction was monitored by TLC. After cooling to room temperature, the volatiles were evaporated. The residue was chromatographed on a silica gel column, further purified by preparative HPLC, and lyophilized to give the product as a white solid (30 mg; 11% yield) and as a mixture of diastereomers (~5:2). 1 H NMR (400MHz, D2O) δppm: 7.51 and 7.45 (d, 1H); 5.98-5.85 (m, 1H); 5.78-5.55 (m, 2H); 4.60-3.70 (m, 7H); 1.16 and 1.15 (s, 9H). ES+MS m / z:376.1(M+1).

[0253] Isopropoxycarbonyloxymethyl ester of cHPMPC (POC-cHPMPC, compound 2)

[0254]

[0255] Tetrabutylammonium hydroxide (0.8 mL; 25% in methanol) was added dropwise to a stirred mixture of cHPMPC (200 mg; 0.766 mmol) in methanol (24 mL) under an inert atmosphere. The mixture was stirred for 10 minutes to dissolve. The solvent was then evaporated and the remaining methanol was removed with dioxane (2×6 mL). The residue was dissolved in dioxane (10 mL) and chloromethyl isopropyl carbonate (0.14 mL; 1.2 equiv.) was added. The mixture was stirred at 90° C. for 1 hour. The reaction was monitored by TLC. After cooling to room temperature, the volatiles were evaporated. The residue was chromatographed on a silica gel column, further purified by preparative HPLC, and lyophilized to give the product as a white solid (30 mg; 11% yield) and as a mixture of diastereomers (~1:1.2). 1 HNMR (400MHz, D2O) δppm: 7.53 and 7.47 (d, 1H); 6.00-5.85 (m, 1H); 5.80-5.60 (m, 2H); 4.98-4.85 (m, 1H); 4.60-3.68 (m, 7H); 1.28 and 1.26 (d, 6H). ES+MS m / z:378.1(M+1).

[0256] Hexadecyloxypropyl ester of cHPMPC (HDP-cHPMPC, compound 3)

[0257]

[0258] A mixture of cHPMPC (200 mg; 0.766 mmol) and N, N'-dicyclohexylmorpholine-4-carboximidamide (240 mg; 1.1 equivalents) in DMF (2 ml) was stirred at room temperature for 12 hours under an inert atmosphere until completely dissolved. Then 1-bromo-3-hexadecyloxypropane (270 mg, 1 equivalent) was added, the mixture was heated to 80 ° C and stirred for 6 hours. The reaction was monitored by TCL. After cooling to room temperature, the mixture was concentrated in vacuo. The residue was chromatographed on a silica gel column, further purified by preparative HPLC, and lyophilized to give the product as a white solid (35 mg; 9% yield) and a mixture of diastereomers (~1: 1.3). 1 H NMR (400 MHz, CDCl3) δ ppm: 7.29 and 7.27 (d, 1H); 5.67 (dd, 1H); 4.48-4.32 (m, 1H); 4.30-4.00 (m, 5H); 3.95-3.34 (m, 5H); 2.05-1.48 (m, 5H); 1.25 (broad s, 27H); 0.88 (t, 3H). ES+MS m / z: 544.5 (M+1).

[0259] Octadecyloxyethyl ester of cHPMPC (ODE-cHPMPC, compound 4)

[0260]

[0261] A mixture of cHPMPC (200 mg; 0.766 mmol) and N, N'-dicyclohexylmorpholine-4-carboximidamide (240 mg; 1.1 equivalents) in DMF (5 ml) was stirred at room temperature for 12 hours under an inert atmosphere. 1-Bromo-2-octadecyloxyethane (289 mg, 1 equivalent) was then added, the mixture was heated to 80 ° C and stirred for 6 hours. After cooling to room temperature, the mixture was concentrated in vacuo. The residue was chromatographed on a silica gel column, further purified by preparative HPLC, and lyophilized to give the product as a white solid (42 mg; 10% yield) and a mixture of diastereomers (~1:1.7). 1H NMR (400MHz, CDCl3) δppm: 7.32 and 7.30 (d, 1H); 5.90-5.78 (m, 1H); 4.48-4.03 (m, 7H); 3 .94-3.82(m,1H); 3.74-3.38(m,5H); 1.70-1.50(m,4H); 1.25(width, 28H); 0.88(t,3H). ES+MS m / z:558.5(M+1).

[0262] Isopropyl L-alanine cHPMPC( Compound 5)

[0263]

[0264] cHPMPC (200 mg; 0.766 mmol) was dissolved in DMF (1 mL) under an inert atmosphere. Benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (500 mg; 1.5 eq.), N,N-diisopropylethylamine (0.3 mL; 2 eq.) and L-alanine isopropyl ester hydrochloride (120 mg; 1 eq.) were added to the stirred solution. The reaction mixture was stirred at 55 °C for 3 hours. The reaction was monitored by TLC. After cooling to room temperature, the mixture was concentrated under vacuum. The residue was chromatographed on a silica gel column, further purified by preparative HPLC, and lyophilized to give the product as a white solid (5 mg; 2% yield) and as a mixture of diastereomers (~1:1). 1 H NMR (400 MHz, D2O) δ ppm: 7.52 (d, 1H), 5.94 and 5.92 (d, 1H); 5.05-4.90 (m, 1H); 4.50-3.60 (m, 8H); 1.37 and 1.32 (d, 3H); 1.25-1.12 (m, 6H). ES+MS m / z: 375.1 (M+1).

[0265] Example 8. Comparative test of compounds 1 to 5 and cHPMPC

[0266] method

[0267] Compounds 1 to 5 and cHPMPC were diluted in PBS and added to porcine bone marrow cells cultured in EBSS supplemented with 10% porcine serum and 1% penicillin-streptomycin in triplicate wells of a 96-well plate at final concentrations of A: 1.0 μM, B: 0.5 μM, C: 0.1 μM, D: 0.05 μM, E: 0.01 μM, F: 0.005 μM, G 0.001 μM.

[0268] Recombinant ASFV genotype II Georgia virus GeorgiaDMGFB infected cells at low multiplicity (0.1 MOI) expressing mNeon green fluorescent protein under the control of ASFV early promoter p30. This reporter gene was inserted in place of four non-essential genes belonging to the multigene families MGF360 and MGF 505 ( https: / / journals.asm.org / doi / 10.1128 / jvi.01899-21 ), and did not result in a reduction in viral replication or virulence. As a control, infected cells without drug treatment were included.

[0269] At 72 h post-infection, cells were visualized using an IncuCyte S3 (Sartorius) to measure the expression of mNeon green fluorescent protein as an indicator of viral infection. Figure 8 As shown in A and 8B, variations in mNeon Green expression were observed at different drug concentrations as a function of the different drugs used for treatment. Of particular interest was the increase in mNeon Green expression at concentrations above 0.05 μM for the compound cHPMPC ( Figure 8 Compared with A, D rows 10, 11, 12), in cells treated with compounds 3 and 4 at concentrations higher than 0.005 μM ( Figure 8 In A, F rows 4, 5, 6 (compound 3) and 7, 8, 9 (compound 4), no mNeon Green expression was observed. These results indicate that the efficacy of compounds 3 and 4 was greatly improved compared to cHPMPC. Figure 8 B) Fluorescence detected in infected cells in the presence of β-lactamase indicated that the efficacy of these compounds was intermediate between compounds 3 and 4 and cHPMPC.

[0270] Compounds 3 and 4 were particularly beneficial and had CCs similar to or lower than cHPMPC (47 + / - 13 or 59 + / - 19 μM in porcine kidney cells). 50 value (50% cytotoxic concentration). This greatly increases the selectivity index to a range of thousands similar to that reported by (Lipka et al., 2023). Therefore, it can be expected that the prepared compounds will be effective at much lower doses.

Claims

1. A cyclocidofovir for use in the treatment of African swine fever (ASF) in an animal, the use comprising orally administering the cyclocidofovir at a dose of 10.0 to 30.0 mg / kg, wherein the animal is administered at least one dose of cyclocidofovir daily, such as one or two doses, in a first period of 1 to 4 consecutive days, and the animal is administered a dose of cyclocidofovir every other day or daily in a second period of 5 to 14 consecutive days, and wherein the average daily dose administered in the first period is higher than the average daily dose administered in the second period.

2. The cyclocidofovir for use according to claim 1, wherein the cyclocidofovir is a compound of formula (i): or their esters, amidates or esteramidates, more particularly their acyloxyalkyl esters, alkoxycarbonyloxyalkyl esters, alkoxyalkyl esters or their phosphoamidates or phosphinamidates.

3. The cyclocidofovir for use according to claim 1 or 2, wherein the cyclocidofovir has a structure of formula (I) or (II), in, A is selected from the group consisting of O and NH; L chooses from -(CR 2 R 3 ) n -、-CH(R 4 )-C(O)- and -C(O)-CH(R 5 )-groups composed of; n is an integer selected from 1, 2, 3, 4 or 5; R 1 Choose from C 6-25 Alkyl, -C(O)R 6 , -CO 2 R 7 , C 6-25 Haloalkyl, C 6-25 Alkenyl, C 6-25 Halogenated alkenyl, C 3-12 Cycloalkyl and C 3-12 The group consisting of halocycloalkyl; Each R 2 are independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; Each R 3 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; Each R 4 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; Each R 5 independently selected from hydrogen, C 1-6 Alkyl, C 3-12 The group consisting of cycloalkyl and halogen; Each R 6 Independently selected from C 1-10 Alkyl, C 1-10 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups; Each R 7 Independently selected from C 1-10 Alkyl, C 1-12 Haloalkyl, C 3-12 Cycloalkyl, C 3-12 Halogenated cycloalkyl, C 2-10 Alkenyl and C 2-10 A group consisting of halogenated alkenyl groups; or stereoisomers, tautomers, solvates, hydrates, or pharmaceutically acceptable salts thereof.

4. The cyclocidofovir used according to claim 3, wherein L chooses from -(CR 2 R 3 ) n - and -CH(R 4 )-C(O)-; n is an integer selected from 1, 2 or 3; R 1 Choose from C 6-25 Alkyl, -C(O)R 6 , -CO 2 R 7 , C 6-25 Haloalkyl, C 6-25 Alkenyl and C 3-10 A group consisting of cycloalkyl groups; Each R 2 independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen; Each R 3 independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen; Each R 4 independently selected from hydrogen, C 1-6 The group consisting of alkyl and halogen; Each R 5 independently selected from hydrogen, C 1-6 Alkyl, C 3-10 The group consisting of cycloalkyl and halogen; Each R 6 Independently selected from C 1-6 Alkyl, C 1-6 Haloalkyl and C 3-6 A group consisting of cycloalkyl groups; Each R 7 Independently selected from C 1-6 Alkyl, C 1-6 Haloalkyl and C 3-6 A group consisting of cycloalkyl.

5. Cycidofovir for use according to any one of claims 3 to 4, selected from the group consisting of:

6. Cycidofovir for use according to any one of claims 1 to 5, wherein the animal is administered two doses of cyclocidofovir per day over a first period of 3 consecutive days and one dose of cyclocidofovir per day over a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days.

7. Cycidofovir for use according to any one of claims 1 to 5, wherein the animal is administered a dose of cyclocidofovir daily for a first period of 3 days and a dose of cyclocidofovir every other day for a second period of 5 to 14 consecutive days, preferably 5 to 7 consecutive days.

8. Ciclocidofovir for use according to any one of claims 1 to 7, wherein the ciclocidofovir is contained in a pharmaceutical composition, preferably wherein the pharmaceutical composition is an aqueous solution.

9. Cicidofovir for use according to any one of claims 1 to 8, wherein the animal is a pig.

10. Ciclocidofovir for use according to any one of claims 1 to 9, wherein the animals are housed in an ASF surveillance area or a protected area.

11. Cicidofovir for use according to any one of claims 1 to 10, wherein the administration of Cicidofovir prevents the spread of ASF in an animal population.

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