USES OF 4'-DESFERRITHIOCIN ANALOGS
20220105078 · 2022-04-07
Assignee
Inventors
Cpc classification
C07D277/10
CHEMISTRY; METALLURGY
International classification
Abstract
Macular degeneration, closed head injury, stroke, irritable bowel disease, and reperfusion injury are all associated with biological injury due to reactive oxygen species, probably due to focal iron overload in many instances. The present invention provides methods and pharmaceutical compositions for treating these diseases and conditions using desferrithiocin analogs of Formula (I). In certain embodiments, the analogs include a poly ether moiety at the 4′-position of the phenyl ring of the compound.
##STR00001##
Claims
1. A method of treating macular degeneration in a subject comprising administering to the subject a therapeutically effective amount of Formula (I): ##STR00017## wherein: R.sub.1 is hydrogen, alkyl, or acyl; R.sub.2 is hydrogen, alkyl, or —[(CH.sub.2).sub.n—O].sub.x—[(CH.sub.2).sub.n—O].sub.y—R′; R.sub.3, R.sub.4, and R.sub.5 are each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10; R.sub.6, R.sub.7, and R.sub.8 are each independently hydrogen, halogen, alkyl, or —OR.sub.12; R.sub.9 is —OR.sub.11 or —SR.sub.11; R.sub.10 is hydrogen, alkyl, or acyl; R.sub.11 is hydrogen or alkyl; R.sub.12 is hydrogen or alkyl; R′ is alkyl; each occurrence of n is independently an integer from 1 to 8, inclusive; x is an integer from 1 to 8, inclusive; and y is an integer from 0 to 8, inclusive; or a pharmaceutically acceptable salt, tautomer, solvate, hydrate, or polymorph thereof.
2. The method of claim 1, wherein the compound is of the Formula (III): ##STR00018##
3. The method of claim 1, wherein R.sub.9 is —OR.sub.11.
4. The method of claim 1, wherein R.sub.9 is —OH.
5. The method of claim 1, wherein R.sub.8 is —CH.sub.3.
6. The method of claim 1, wherein R.sub.6 and R.sub.7 are each hydrogen.
7. The method of claim 1, wherein R.sub.3, R.sub.4, and R.sub.5 are each hydrogen.
8. The method of claim 1, wherein R.sub.1, R.sub.3, R.sub.4, and R.sub.5 are each hydrogen.
9. The method of claim 1, wherein R.sub.2 is —[(CH.sub.2).sub.n—O].sub.x—R′; n is 2 to 4; and x is 1 to 4.
10. The method of claim 1, wherein R.sub.2 is —[(CH.sub.2).sub.n—O].sub.x—R′; n is 2; x is 3; and R′ is —CH.sub.3.
11. The method of claim 1, wherein R.sub.2 is —[(CH.sub.2).sub.n—O].sub.x—R′; n is 2; x is 2; and R′ is —CH.sub.3.
12. The method of claim 1, wherein the compound is of the Formula (III-A): ##STR00019##
13. The method of claim 1, wherein the compound is of the Formula (III-B) or (III-C): ##STR00020##
14. (canceled)
15. The method of claim 1, wherein the compound is of the Formula (IV-A): ##STR00021##
16. The method of claim 1, wherein the compound is of the Formula (IV-B) or (IV-C): ##STR00022##
17. (canceled)
18. The method of claim 1, wherein the compound is of the Formula (V-A), (V-B), or (V-C): ##STR00023##
19-20. (canceled)
21. A method of treating a closed head injury in a subject comprising administering to the subject a therapeutically effective amount of a compound of Formula (I): ##STR00024## wherein: R.sub.1 is hydrogen, alkyl, or acyl; R.sub.2 is hydrogen, alkyl, or —[(CH.sub.2).sub.n—O].sub.x—[(CH.sub.2).sub.n—O].sub.y—R′; R.sub.3, R.sub.4, and R.sub.5 are each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10; R.sub.6, R.sub.7, and R.sub.8 are each independently hydrogen, halogen, alkyl, or —OR.sub.12; R.sub.9 is —OR.sub.11 or —SR.sub.11; R.sub.10 is hydrogen, alkyl, or acyl; R.sub.11 is hydrogen or alkyl; R.sub.12 is hydrogen or alkyl; R′ is alkyl; each occurrence of n is independently an integer from 1 to 8, inclusive; x is an integer from 1 to 8, inclusive; and y is an integer from 0 to 8, inclusive; or a pharmaceutically acceptable salt, tautomer, solvate, hydrate, or polymorph thereof.
22-86. (canceled)
87. A method of treating reperfusion injury in a subject comprising administering to the subject a therapeutically effective amount of a compound of Formula (I): ##STR00025## wherein: R.sub.1 is hydrogen, alkyl, or acyl; R.sub.2 is hydrogen, alkyl, or —[(CH.sub.2).sub.n—O].sub.x—[(CH.sub.2).sub.n—O].sub.y—R′; R.sub.3, R.sub.4, and R.sub.5 are each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10; R.sub.6, R.sub.7, and R.sub.8 are each independently hydrogen, halogen, alkyl, or —OR.sub.12; R.sub.9 is —OR.sub.11 or —SR.sub.11; R.sub.10 is hydrogen, alkyl, or acyl; R.sub.11 is hydrogen or alkyl; R.sub.12 is hydrogen or alkyl; R′ is alkyl; each occurrence of n is independently an integer from 1 to 8, inclusive; x is an integer from 1 to 8, inclusive; and y is an integer from 0 to 8, inclusive; or a pharmaceutically acceptable salt, tautomer, solvate, hydrate, or polymorph thereof.
88-111. (canceled)
112. The method of claim 1, wherein the compound is of Formula (I): ##STR00026## or a pharmaceutically acceptable salt thereof.
113. The method of claim 1, wherein R′ is C.sub.1-C.sub.6 alkyl.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0082]
[0083]
[0084]
[0085]
[0086]
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION
[0087] Various desferrithiocin analogs have been described for use in the treatment of global iron overload resulting from transfusion therapy, high-iron diet, acute iron ingestion, or malabsorption. Such analogs have now been discovered to be useful in treating or preventing diseases and conditions associated with focal iron overload, where the local concentration of iron in a particular tissue or organ contributes to the pathological process. For instance, the unmanaged Fe.sup.+2 ions in a tissue or organ may result in the production of hydroxyl radicals or other reactive oxygen species that lead to tissue or cell damage. Therefore, desferrithiocin analogs of Formula (I), particularly those with a polyether moiety at the 4′-position of the phenyl ring, are expected to be useful in the treatment of macular degeneration, closed head injury, reperfusion injury, and stroke. Without wishing to be bound by any particular theory, the compounds of Formula (I) are thought to chelate iron and prevent it from participating in the generation of reactive oxygen species. The compounds of Formula (I) may also act as free radical scavenger thereby limiting the damage of reactive oxygen species or other radicals. The invention, therefore, provides methods of treating and preventing disease and conditions associated with focal iron overload, as well as pharmaceutical compositions and kits useful in the inventive methods.
Useful Compounds
[0088] Desferrithiocin analogs of Formula (I) are expected to be useful in preventing and treating diseases and conditions associated with iron overload, particularly focal iron overload. Such analogs have been previously described in International PCT Applications, PCT/US2006/010945, filed Mar. 22, 2006, WO2006/017626, and PCT/US2010/002336, filed Aug. 25, 2010, published as WO2011/028255; and U.S. patent application U.S. Ser. No. 11/973,001, filed Oct. 4, 2007, published as US2008/0214630; each of which is incorporated herein by reference. Compounds with a poly ether moiety at the 4′-position of the phenyl ring are expected to be particularly useful in the methods and compositions of the present invention.
[0089] In certain embodiments, compounds useful in the present invention are of Formula (I):
##STR00004##
wherein: [0090] R.sub.1 is hydrogen, alkyl, or acyl; [0091] R.sub.2 is hydrogen, alkyl, or —[(CH.sub.2).sub.n—O].sub.x—[(CH.sub.2).sub.n—O].sub.y—R′; [0092] R.sub.3, R.sub.4, and R.sub.5 are each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10; [0093] R.sub.6, R.sub.7, and R.sub.8 are each independently hydrogen, halogen, alkyl, or —OR.sub.12; [0094] R.sub.9 is —OR.sub.11 or —SR.sub.11; [0095] R.sub.10 is hydrogen, alkyl, or acyl; [0096] R.sub.11 is hydrogen or alkyl; [0097] R.sub.12 is hydrogen or alkyl; [0098] R′ is alkyl; [0099] each occurrence of n is independently an integer from 1 to 8, inclusive; [0100] x is an integer from 1 to 8, inclusive; and [0101] y is an integer from 0 to 8, inclusive;
or a pharmaceutically acceptable salt, tautomer, solvate, hydrate, or polymorph thereof.
[0102] In compounds of Formula (I), R.sup.1 is hydrogen, alkyl, or acyl. In certain embodiments, R.sup.1 is hydrogen. In certain embodiments, R.sup.1 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sup.1 is methyl. In certain embodiments, R.sup.1 is ethyl. In certain embodiments, R.sup.1 is propyl. In certain embodiments, R.sup.1 is acyl. In certain embodiments, R.sup.1 is acetyl.
[0103] In compounds of Formula (I), R.sub.2 is hydrogen, alkyl, or —[(CH.sub.2).sub.n—O].sub.x—[(CH.sub.2).sub.n—O].sub.y—R′. In certain embodiments, R.sub.2 is hydrogen. In certain embodiments, R.sub.2 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.2 is methyl. In certain embodiments, R.sub.2 is ethyl. In certain embodiments, R.sub.2 is propyl. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.n—0]x-[(CH.sub.2).sub.n—O].sub.y—R′. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.2—O]—CH.sub.3. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.2—O].sub.2—CH.sub.3. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.2—O].sub.3—CH.sub.3. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.2—O].sub.4—CH.sub.3. In certain embodiments, R.sub.2 is —[(CH.sub.2).sub.2—O].sub.5—CH.sub.3.
[0104] In compounds of Formula (I), n is an integer from 1 to 8, inclusive. In certain embodiments, n is 2. In certain embodiments, n is 3. In certain embodiments, n is 4. In certain embodiments, n is 5.
[0105] In compounds of Formula (I), x is an integer from 1 to 8, inclusive. In certain embodiments, x is 1. In certain embodiments, x is 2. In certain embodiments, x is 3. In certain embodiments, x is 4. In certain embodiments, x is 5.
[0106] In compounds of Formula (I), y is an integer from 0 to 8, inclusive. In certain embodiments, y is 0. In certain embodiments, y is 1. In certain embodiments, y is 2. In certain embodiments, y is 3. In certain embodiments, y is 4. In certain embodiments, y is 5.
[0107] In compounds of Formula (I), R′ is alkyl. In certain embodiments, R′ is C.sub.1-C.sub.6 alkyl. In certain embodiments, R′ is methyl. In certain embodiments, R′ is ethyl. In certain embodiments, R′ is propyl.
[0108] In compounds of Formula (I), R.sub.3 is each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10. In certain embodiments, R.sub.3 is hydrogen. In certain embodiments, R.sub.3 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.3 is methyl. In certain embodiments, R.sub.3 is ethyl. In certain embodiments, R.sub.3 is propyl. In certain embodiments, R.sub.3 is —OH. In certain embodiments, R.sub.3 is —OCH.sub.3.
[0109] In compounds of Formula (I), R.sub.4 is each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10. In certain embodiments, R.sub.4 is hydrogen. In certain embodiments, R.sub.4 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.4 is methyl. In certain embodiments, R.sub.4 is ethyl. In certain embodiments, R.sub.4 is propyl. In certain embodiments, R.sub.4 is —OH. In certain embodiments, R.sub.4 is —OCH.sub.3.
[0110] In compounds of Formula (I), R.sub.5 is each independently hydrogen, alkyl, arylalkyl, or —OR.sub.10. In certain embodiments, R.sub.5 is hydrogen. In certain embodiments, R.sub.5 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.5 is methyl. In certain embodiments, R.sub.5 is ethyl. In certain embodiments, R.sub.5 is propyl. In certain embodiments, R.sub.5 is —OH. In certain embodiments, R.sub.5 is —OCH.sub.3.
[0111] In certain embodiments, R.sub.3, R.sub.4, and R.sub.5 are all hydrogen. In certain embodiments, at least one of R.sub.3, R.sub.4, and R.sub.5 is hydrogen. In certain embodiments, at least two of R.sub.3, R.sub.4, and R.sub.5 are hydrogen.
[0112] In compounds of Formula (I), R.sub.6 is hydrogen, halogen, alkyl, or —OR.sub.12. In certain embodiments, R.sub.6 is hydrogen. In certain embodiments, R.sub.6 is halogen. In certain embodiments, R.sub.6 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.6 is methyl. In certain embodiments, R.sub.6 is ethyl. In certain embodiments, R.sub.6 is propyl. In certain embodiments, R.sub.6 is —OH. In certain embodiments, R.sub.6 is —OCH.sub.3.
[0113] In compounds of Formula (I), R.sub.7 is hydrogen, halogen, alkyl, or —OR.sub.12. In certain embodiments, R.sub.7 is hydrogen. In certain embodiments, R.sub.7 is halogen. In certain embodiments, R.sub.7 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.7 is methyl. In certain embodiments, R.sub.7 is ethyl. In certain embodiments, R.sub.7 is propyl. In certain embodiments, R.sub.7 is —OH. In certain embodiments, R.sub.7 is —OCH.sub.3.
[0114] In certain embodiments, both R.sub.6 and R.sub.7 are hydrogen. In certain embodiments, at least one of R.sub.6 and R.sub.7 is hydrogen.
[0115] In compounds of Formula (I), R.sub.8 is hydrogen, halogen, alkyl, or —OR.sub.12. In certain embodiments, R.sub.8 is hydrogen. In certain embodiments, R.sub.8 is halogen. In certain embodiments, R.sub.8 is C.sub.1-C.sub.6 alkyl. In certain embodiments, R.sub.8 is methyl. In certain embodiments, R.sub.8 is ethyl. In certain embodiments, R.sub.8 is propyl. In certain embodiments, R.sub.8 is —OH. In certain embodiments, R.sub.8 is —OCH.sub.3.
[0116] In compounds of Formula (I), R.sub.9 is —OR.sub.11 or —SR.sub.11, wherein R.sub.11 is hydrogen or alkyl. In certain embodiments, R.sub.9 is —OH. In certain embodiments, R.sub.9 is —OCH.sub.3. In certain embodiments, R.sub.9 is —OCH.sub.2CH.sub.3. In certain embodiments, R.sub.9 is —OCH(CH.sub.3).sub.2. In certain embodiments, R.sub.9 is —SCH.sub.3. In certain embodiments, R.sub.9 is —SCH.sub.2CH.sub.3. In certain embodiments, R.sub.9 is —SCH.sub.2CH.sub.2CH.sub.3. In certain embodiments, R.sub.9 is —SCH(CH.sub.3).sub.2. In certain embodiments, R.sub.9 is —SCH.sub.2CH(CH.sub.3).sub.2. In certain embodiments, R.sub.11 is hydrogen. In certain embodiments, R.sub.11 is C.sub.1-C.sub.6 alkyl.
[0117] In certain embodiments, R.sub.6 is hydrogen, R.sub.7 is hydrogen, and R.sub.8 is methyl.
[0118] In certain embodiments, R.sub.3 is hydrogen, R.sub.4 is hydrogen, R.sub.5 is hydrogen, R.sub.6 is hydrogen, R.sub.7 is hydrogen, and R.sub.8 is methyl.
[0119] In certain embodiments, R.sub.1 is hydrogen, R.sub.3 is hydrogen, R.sub.4 is hydrogen, R.sub.5 is hydrogen, R.sub.6 is hydrogen, R.sub.7 is hydrogen, and R.sub.8 is methyl.
[0120] In certain embodiments, R.sub.1 is hydrogen, R.sub.3 is hydrogen, R.sub.4 is hydrogen, R.sub.5 is hydrogen, R.sub.6 is hydrogen, R.sub.7 is hydrogen, R.sub.8 is methyl, and R.sub.9 is —OH.
[0121] The compounds of Formula (I) may be provided in various salts forms. In certain embodiments, when R.sub.9 is —OH, the compound may be provided as a carboxylate salt with a positively charged counterion. In certain embodiments, the counterion is betaine, choline hydroxide, diethanolamine, diethylamine, ethanolamine, hydroxyethylmorpholine, 4-(2-hydroxyethyl morpholine), 1-(2-hydroxyethyl pyrrolidine), 1-(2-hydroxyethyl)-piperidine, 1,2-EDSA, HCl, H.sub.2SO.sub.4, MSA, p-TSA, hydroxyethyl pyrrolidine, imidazone, lysine (e.g., L-lysine), arginine (e.g., L-arginine), histidine (e.g., L-histidine) N-methyl-D-glucamine (NMG), N, N′-dibenzyl-ethylenediamine, N, N′-diethyl-ethanolamine, triethanolamine, tromethamine, calcium (e.g., Ca(OH).sub.2), magnesium (e.g., Mg(OH).sub.2, magnesium acetate), potassium (e.g., KOH, potassium 2-ethylhexanoate), sodium (e.g., NaOH, sodium acetate, sodium 2-ethylhexanoate), zinc (e.g., Zn(OH).sub.2, zinc acetate), Zn(OH).sub.2/Mg(OH).sub.2, EDA, or piperazine. In certain embodiments, the counterion is lysine. In certain embodiments, the counterion is N-methyl-D-glucamine (NMG). In certain embodiments, the counterion is tromethamine. In certain embodiments, the counterion is calcium. In certain embodiments, the counterion is magnesium. In certain embodiments, the counterion is potassium. In certain embodiments, the counterion is sodium, In certain embodiments, the counterion is zinc. In certain embodiments, the counterion is piperazine. In certain embodiments, the counterion is MgOH.sup.+. In certain embodiments, the counterion is ZnOH.sup.+.
[0122] In certain embodiments, a polymorph of a salt of a compound of Formula (I) is provided. In certain embodiments, a polymorph of a magnesium salt of a compound of Formula (I) is provided. In certain embodiments, a polymorph of a MgOH.sup.+ salt of a compound of Formula (I) is provided. In certain embodiments, a polymorph of a salt of a carboxylate compound of Formula (I), wherein R.sub.9 is —OH, is provided. In certain embodiments, a polymorph of a magnesium salt of a carboxylate compound of Formula (I), wherein R.sub.9 is —OH, is provided. In certain embodiments, a polymorph of a MgOH.sup.+ salt of a carboxylate compound of Formula (I), wherein R.sub.9 is —OH, is provided.
[0123] In certain embodiments, the compound of Formula (I) is of Formula (III):
##STR00005##
[0124] In certain embodiments, the compound of Formula I) is of Formula (III-A):
##STR00006##
[0125] In certain embodiments, a salt of a compound of Formula (III-A) is provided. In certain embodiments, a magnesium hydroxide salt of Formula (III-A) is provided as shown in Formula (III-A′):
##STR00007##
[0126] In certain embodiments, the compound of Formula (I) is of Formula (III-B):
##STR00008##
[0127] In certain embodiments, the compound of Formula (I) is of Formula (III-C):
##STR00009##
[0128] In certain embodiments, the compound of Formula (I) is of Formula (IV-A):
##STR00010##
[0129] In certain embodiments, a salt of a compound of Formula (IV-A) is provided. In certain embodiments, a magnesium hydroxide salt of Formula (IV-A) is provided as shown in Formula (IV-A′):
##STR00011##
[0130] In certain embodiments, the compound of Formula (I) is of Formula (IV-B):
##STR00012##
[0131] In certain embodiments, the compound of Formula (I) is of Formula (IV-C):
##STR00013##
[0132] In certain embodiments, the compound of Formula (I) is of Formula (V-A):
##STR00014##
[0133] In certain embodiments, the compound of Formula (I) is of Formula (V-B):
##STR00015##
[0134] In certain embodiments, the compound of Formula (I) is of Formula (V-C):
##STR00016##
Treatment of Macular Degeneration
[0135] In one aspect, the invention provides methods and pharmaceutical compositions for the treatment of macular degeneration. Without wishing to be bound by a particular theory, the compounds of Formula (I) are able to get into the eye as shown in
[0136] In the treatment of macular degeneration, the compound of Formula (I) or a pharmaceutical composition thereof may be administered systemically or ocularly. In certain embodiments, the compound or composition is administered orally. In other embodiments, the compound or composition is administered to the eye using eyedrops or an ointment suitable for ocular administration.
[0137] The subject being treated for macular degeneration may be any type of animal. In certain embodiments, the animal is a mammal. In certain embodiments, the animal is a human. In certain embodiments, the animal is a domesticated animal (e.g., dog, cat, pig, cow). In certain embodiments, the animal is a research animal (e.g., mice, rat, dog, primate).
[0138] The exact amount of the compound of Formula (I) required to treat or prevent macular degeneration will vary from subject to subject, depending on the species, age, and general condition of the subject, the particular agent being administered, its mode of administration, and the like. The compound is preferably formulated in a dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily dosage will be decided by a physician within the scope of sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the severity of the macular degeneration; the specific compound be administered; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the particular compound being administered; the duration of the treatment; drugs used in combination or coincidental with the particular compound being administered; and like factors well known in the medical arts. In certain embodiments, the daily dosage of the compound of Formula (I) for the treatment of macular degeneration in a subject may range from 0.01 mg/kg to 200 mg/kg per unit dosage. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 100 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 50 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 20 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 10 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 1 mg/kg. In certain embodiments, the compound or a composition thereof may be administered once a day to multiple times per day. In certain embodiments, a fraction of the daily dose is administered once, twice, three times, or four times daily. In other embodiments, the compound of a composition thereof is administered every other day, every third day, every week, every other week, or every month.
Treatment of Head Injury
[0139] The compounds of Formula (I) and pharmaceutical compositions thereof are expected to be useful in the treatment of head injury, particularly those involving bleeding into the brain or other parts of the central nervous system. Without wishing to be bound by any particular theory, the compounds of Formula (I) are thought to chelate the iron from red blood cells the blood resulting from the head injury, thereby preventing iron ions from generating reactive oxygen species. In the case of head injury resulting in bleeding into the central nervous system where the vasculature has been compromised a compound being used may or may not have the ability to cross the blood brain barrier. In certain embodiments, the compound being used to treat a head injury in a subject is able to cross the blood brain barrier. In other embodiments, the compounds is not able to cross the blood brain barrier. Certain compounds of Formula (I) have been found in the CSF after systemic administration (po and sc).
[0140] Head injuries come in various forms and results from various causes. In certain embodiments, the injury is an injury to the head that penetrates the skull. In other embodiments, the head injury being treated is a closed head injury, which does penetrate the skull. Closed head injuries results from a variety of causes including accidents including vehicular accidents, falls, and assaults. Types of closed head injuries include concussions, brain contusions, diffuse axonal injury, and hematoma. In certain embodiments, the closed head injury being treated in the present invention include closed head injuries that result in blood outside the blood vessels of the brain. The local accumulation of iron from the bleeding is thought to contribute to after effects of closed head injury. By assisting the clearance of iron from the brain the effects of the bleed are minimized.
[0141] In the treatment of closed head injury, the compound of Formula (I) or a pharmaceutical composition thereof may be administered systemically, for example, parenterally or orally. In certain embodiments, the compound or composition is administered orally. In other embodiments, the compound or composition is administered parenterally (e.g., intravenously).
[0142] The subject being treated for a head injury may be any type of animal. In certain embodiments, the animal is a mammal. In certain embodiments, the animal is a human. In certain embodiments, the animal is a domesticated animal (e.g., dog, cat, pig, cow). In certain embodiments, the animal is a research animal (e.g., mice, rat, dog, primate).
[0143] The exact amount of the compound of Formula (I) required to treat a head injury will vary from subject to subject, depending on the species, age, and general condition of the subject, the particular agent being administered, its mode of administration, and the like. The compound is preferably formulated in a dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily dose will be decided by a physician using sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the severity of the head injury; the specific compound be administered; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the particular compound being administered; the duration of the treatment; drugs used in combination or coincidental with the particular compound being administered; and like factors well known in the medical arts. In certain embodiments, the daily dosage of the compound of Formula (I) for the treatment of a head injury in a subject may range from 0.01 mg/kg to 200 mg/kg per unit dosage. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 100 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 50 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 20 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 10 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 1 mg/kg. In certain embodiments, the compound or a composition thereof may be administered once a day to multiple times per day. In certain embodiments, a fraction of the daily dose is administered once, twice, three times, or four times daily. In other embodiments, the compound of a composition thereof is administered every other day, every third day, every week, every other week, or every month. In certain embodiments, the inventive treatment is stopped once the head injury is resolved, or it is thought the inventive treatment would no longer be beneficial. In certain embodiments, the treatment is stopped once the bleeding has been resolved in a subject with a head injury.
Treatment of Stroke
[0144] The present invention also provides for the treatment of stroke. The inventive treatment typically leads to a better and/or faster recovery from stroke. The stroke being treated may be either a ischemic stroke or a hemorrhagic stroke. In the treatment of an ischemic stroke, a compound of Formula (I) or composition thereof is administered to a subject to prevent or minimize the damage due to reperfusion injury after the blood supply to the affected part of the brain is restore. The compound is thought to prevent the generation of reactive oxygen species by either chelating iron responsible for the generation of such species and/or quenching such radical species when they do occur. In hemorrhagic stroke, the compound is thought to work by similar mechanisms although the sequestering of iron from the blood in the brain is probably the predominate mechanism by which the inventive treatment works. The mechanism of action of the compound of Formula (I) is similar to that in the treatment of head injury.
[0145] The compound being used in the treatment may have the ability to cross the blood brain barrier. In certain embodiments, the compound has the ability to cross the blood brain barrier. In other embodiments, the compound does not have the ability to cross the blood brain barrier. In certain embodiments, when the subject has been diagnosed with an ischemic stroke, the compound used in the treatment can pass through the blood brain barrier.
[0146] The present invention may be useful in treating a subject after the subject has been diagnosed with having a stroke, or a subject who is susceptible to having a stroke may be administered a compound of Formula (I) or composition thereof to prevent or minimize the stroke's effects. In certain embodiments, the compound is administered as quickly as possible after a subject has been diagnosed with having a stroke. In certain embodiments, the compound is administered to the subject while the stroke is still occurring. In certain embodiments, the compound or a composition thereof is administered to a subject who has a history of strokes or is susceptible to having a stroke because of the subject's underlying medical condition. The compound or composition thereof may be administered once or multiple times in the treatment of stroke.
[0147] In the treatment of stroke the compound of Formula (I) or a pharmaceutical composition thereof may be administered systemically, for example, parenterally or orally. In certain embodiments, the compound or composition is administered orally. In other embodiments, the compound or composition is administered parenterally (e.g., intravenously).
[0148] The subject being treated for stroke may be any type of animal. In certain embodiments, the animal is a mammal. In certain embodiments, the animal is a human. In certain embodiments, the animal is a domesticated animal (e.g., dog, cat, pig, cow). In certain embodiments, the animal is a research animal (e.g., mice, rat, dog, primate).
[0149] The exact amount of the compound of Formula (I) required to treat a stroke will vary from subject to subject, depending on the species, age, and general condition of the subject, the particular agent being administered, its mode of administration, and the like. The compound is preferably formulated in a dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily dose will be decided by a physician using sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the severity of the stroke; the specific compound be administered; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the particular compound being administered; the duration of the treatment; drugs used in combination or coincidental with the particular compound being administered; and like factors well known in the medical arts. In certain embodiments, the daily dosage of the compound of Formula (I) for the treatment of a stroke in a subject may range from 0.01 mg/kg to 200 mg/kg per unit dosage. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 100 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 50 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 20 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 10 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 1 mg/kg. In certain embodiments, the compound or a composition thereof may be administered once a day to multiple times per day. In certain embodiments, a fraction of the daily dose is administered once, twice, three times, or four times daily. In other embodiments, the compound or a composition thereof is administered every other day, every third day, every week, every other week, or every month. Typically the compound or composition thereof is not administered after it is no longer thought to be beneficial, for example, when all the bleeding has been cleared in a hemorrhagic stroke.
Treatment of Inflammatory Bowel Disease
[0150] Reactive oxygen species have been implicated in the pathogenesis of inflammatory bowel disease (IBD). Grisham et al., “Neutophil-mediated mucosal injury. Role of reactive oxygen metabolites” Dig. Dis. Sci. 33:6S-15S, 1988; Allgayer “Clinical relevance of oxygen radicals in inflammatory bowel disease-facts and fashion” Klin. Wochenschr. 69:1001-1003, 1991; Ymamada et al. “Role of neutrophil-derived oxidants in the pathogenesis of intestinal inflammation” Klin. Wocheschr. 69:988-944, 1991; Babbs, “Oxygen radicals in ulcerative colitis” Free Radic. Biol. Med. 13:169-181, 1992. The present invention provides for the treatment of IBD. DFO, an iron chelator, has been discovered to prevent acetic acid-induced colitis in rats, an animal model of IBD. See
[0151] The present invention may be useful in treating a subject diagnosed with IBD. The treatment may be used to treat the subject long term or may be used to treat a subject with a fare up of IBD. A therapeutically effective amount of a compound of Formula (I) or composition thereof is administered to a subject in need thereof to treat IBD. In certain embodiments, treatment with a compound of Formula (I) leads to reduced levels of reactive oxygen species in the intestines, specifically the intestinal mucosa. The compound or composition thereof may be administered to a subject once or multiple times in the treatment of IBD.
[0152] In the treatment of IBD, the compound of Formula (I) or a pharmaceutical composition thereof may be administered systemically, for example, parenterally or orally. In certain embodiments, the compound or composition is administered orally. In other embodiments, the compound or composition is administered parenterally (e.g., intravenously). In certain embodiments, the compound or a composition is administered rectally.
[0153] The subject being treated for IBD may be any type of animal. In certain embodiments, the animal is a mammal. In certain embodiments, the animal is a human. In certain embodiments, the animal is a domesticated animal (e.g., dog, cat, pig, cow). In certain embodiments, the animal is a research animal (e.g., mice, rat, dog, primate). In certain embodiments, the animal is used in animal model of IBD (e.g., acetic acid-induced colitis in rats; see Fedorak et al., “Misoprostol provides a colonic mucosal protective effect during acetic acid-induced colitis in rats” Gastroenterology 98:615-625, 1990; MacPherson et al., “Experimental production of diffuse colitis in rats” Digestion 17:135-150, 1978).
[0154] The exact amount of the compound of Formula (I) required to treat IBD will vary from subject to subject, depending on the species, age, and general condition of the subject, the particular agent being administered, its mode of administration, and the like. The compound is preferably formulated in a dosage unit form for ease of administration and uniformity of dosage. The total daily dose will be decided by a physician using sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the severity of IBD; the specific compound be administered; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the particular compound being administered; the duration of the treatment; drugs used in combination or coincidental with the particular compound being administered; and like factors well known in the medical arts. In certain embodiments, the daily dosage of the compound of Formula (I) for the prevention or treatment of reperfusion injury in a subject may range from 0.01 mg/kg to 200 mg/kg per unit dosage. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 100 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 50 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 20 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 10 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 1 mg/kg. In certain embodiments, the compound or a composition thereof may be administered once a day to multiple times per day. In certain embodiments, a fraction of the daily dose is administered once, twice, three times, or four times daily. In other embodiments, the compound or a composition thereof is administered every other day, every third day, every week, every other week, or every month.
Treatment of Reperfusion Injury
[0155] The present invention also provides for the treatment of reperfusion injury. Reperfusion injury may occur in any area of the body where the blood supply has been compromised. In certain embodiments, the reperfusion injury being treated occurs in the heart. In other embodiments, the reperfusion injury occurs in the brain, for example, as discussed above in the context of a stroke The inventive treatment minimizes reperfusion injury once the blood supply to the affects organ or tissue is restored. In the treatment or prevention of reperfusion injury, a compound of Formula (I) or composition thereof is administered to a subject who is suffering from ischemia of a tissue or organ. The compound of Formula (I) is thought to prevent the generation of reactive oxygen species by either chelating iron responsible for the generation of such species and/or quenching such radical species when they do occur.
[0156] The present invention may be useful in treating a subject after the subject has been diagnosed with ischemia of a particular organ or tissue. A therapeutically effective amount of a compound of Formula (I) or composition thereof is administered to a subject to prevent or minimize reperfusion injury. In certain embodiments, the compound is administered as quickly as possible after a subject has been diagnosed with ischemia. In certain embodiments, the compound is administered to the subject at risk of ischemia. In certain embodiments, the compound or a composition thereof is administered to a subject who is about to undergo a procedure that may lead to ischemia of an organ or tissue (e.g., cardiac surgery). In certain embodiments, the compound or a composition thereof is used to prevent reperfusion injury in a transplanted organ. In certain embodiments, the compound or composition thereof is used to perfuse an isolated organ being prepared for donation. The compound or composition thereof may be administered to a subject once or multiple times in the treatment of reperfusion injury.
[0157] In the prevention or treatment of reperfusion injury, the compound of Formula (I) or a pharmaceutical composition thereof may be administered systemically, for example, parenterally or orally. In certain embodiments, the compound or composition is administered orally. In other embodiments, the compound or composition is administered parenterally (e.g., intravenously). In certain embodiments, the compound or a composition is administered locally to the organ or tissue suffering from ischemia.
[0158] The subject being treated for reperfusion injury may be any type of animal. In certain embodiments, the animal is a mammal. In certain embodiments, the animal is a human. In certain embodiments, the animal is a domesticated animal (e.g., dog, cat, pig, cow). In certain embodiments, the animal is a research animal (e.g., mice, rat, dog, primate).
[0159] The exact amount of the compound of Formula (I) required to prevent or treat reperfusion injury will vary from subject to subject, depending on the species, age, and general condition of the subject, the particular agent being administered, its mode of administration, and the like. The compound is preferably formulated in a dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily dose will be decided by a physician using sound medical judgment. The specific therapeutically effective dose level for any particular subject will depend upon a variety of factors including the severity of the reperfusion injury; the specific compound be administered; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the particular compound being administered; the duration of the treatment; drugs used in combination or coincidental with the particular compound being administered; and like factors well known in the medical arts. In certain embodiments, the daily dosage of the compound of Formula (I) for the prevention or treatment of reperfusion injury in a subject may range from 0.01 mg/kg to 200 mg/kg per unit dosage. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 100 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 50 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 20 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 10 mg/kg. In certain embodiments, the daily dosage ranges from 0.1 mg/kg to 1 mg/kg. In certain embodiments, the compound or a composition thereof may be administered once a day to multiple times per day. In other embodiments, the compound or a composition thereof is administered every other day, every third day, every week, every other week, or every month. Typically the compound or composition thereof is not administered after it is no longer thought to be beneficial, for example, when the risk of reperfusion injury is over.
Pharmaceutical Compositions
[0160] The present invention also provides pharmaceutical compositions of Formula (I) for the treatment of macular degeneration, closed head injury, stroke, IBD, and reperfusion injury. After formulation with an appropriate pharmaceutically acceptable excipient in a desired dosage, the pharmaceutical compositions of this invention can be administered to humans and other animals orally, rectally, parenterally, intracisternally, intraperitoneally, topically, bucally, ocularly, or the like, depending on the disease or condition being treated. In certain embodiments, an agent of the invention may be administered orally or parenterally at dosage levels sufficient to deliver from about 0.001 mg/kg to about 200 mg/kg, about 0.001 mg/kg to about 100 mg/kg, about 0.01 mg/kg to about 100 mg/kg, from about 0.01 mg/kg to about 50 mg/kg, preferably from about 0.1 mg/kg to about 40 mg/kg, preferably from about 0.5 mg/kg to about 30 mg/kg, from about 0.01 mg/kg to about 10 mg/kg, from about 0.1 mg/kg to about 10 mg/kg, and more preferably from about 1 mg/kg to about 25 mg/kg, of subject body weight per day, one or more times a day, to obtain the desired therapeutic effect. The desired dosage may be delivered three times a day, two times a day, once a day, every other day, every third day, every week, every two weeks, every three weeks, or every four weeks. In certain embodiments, the desired dosage may be delivered using multiple administrations (e.g., two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, or more administrations). In certain embodiments, a compound of Formula (I) is administered at a dose that is below the dose at which the agent causes non-specific effects. In certain embodiments, a compound of Formula (I) is administered at a dose that does not cause generalized immunosuppression in a subject.
[0161] Liquid dosage forms for oral and parenteral administration include, but are not limited to, pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups, and elixirs. In addition to the active agents, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof. Besides inert diluents, oral compositions can also include adjuvants such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents. In certain embodiments for parenteral administration, agents of the invention are mixed with solubilizing agents such CREMOPHOR EL® (polyethoxylated castor oil), alcohols, oils, modified oils, glycols, polysorbates, cyclodextrins, polymers, and combinations thereof.
[0162] Injectable preparations, for example, sterile injectable aqueous or oleaginous suspensions, may be formulated according to the known art using suitable dispersing or wetting agents and suspending agents. Sterile injectable preparation may also be a sterile injectable solution, suspension or emulsion in a nontoxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution, U.S.P. and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid are used in the preparation of injectables.
[0163] Injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use.
[0164] Compositions for rectal or vaginal administration are preferably suppositories which can be prepared by mixing the compounds of this invention with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol, or a suppository wax which are solid at ambient temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the active agent.
[0165] Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In such solid dosage forms, the active agent is mixed with at least one inert, pharmaceutically acceptable excipient or carrier such as sodium citrate or dicalcium phosphate and/or a) fillers or extenders such as starches, lactose, sucrose, glucose, mannitol, and silicic acid, b) binders such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidinone, sucrose, and acacia, c) humectants such as glycerol, d) disintegrating agents such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate, e) solution retarding agents such as paraffin, f) absorption accelerators such as quaternary ammonium compounds, g) wetting agents such as, for example, cetyl alcohol and glycerol monostearate, h) absorbents such as kaolin and bentonite clay, and i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, and mixtures thereof. In the case of capsules, tablets and pills, the dosage form may also comprise buffering agents.
[0166] Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like. The solid dosage forms of tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings and other coatings well known in the pharmaceutical formulating art. They may optionally contain opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions which can be used include polymeric substances and waxes. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.
[0167] The active agents can also be in micro-encapsulated form with one or more excipients as noted above. The solid dosage forms of tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings, release controlling coatings and other coatings well known in the pharmaceutical formulating art. In such solid dosage forms the active agent may be admixed with at least one inert diluent such as sucrose, lactose or starch. Such dosage forms may also comprise, as is normal practice, additional substances other than inert diluents, e.g., tableting lubricants and other tableting aids such a magnesium stearate and microcrystalline cellulose. In the case of capsules, tablets, and pills, the dosage forms may also comprise buffering agents. They may optionally contain opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions which can be used include polymeric substances and waxes.
[0168] Formulations suitable for topical administration include liquid or semi-liquid preparations such as liniments, lotions, gels, applicants, oil-in-water or water-in-oil emulsions such as creams, ointments, or pastes; or solutions or suspensions such as drops. Formulations for topical administration to the skin surface can be prepared by dispersing the drug with a dermatologically acceptable carrier such as a lotion, cream, ointment, or soap. Useful carriers are capable of forming a film or layer over the skin to localize application and inhibit removal. For topical administration to internal tissue surfaces, the agent can be dispersed in a liquid tissue adhesive or other substance known to enhance adsorption to a tissue surface. For example, hydroxypropylcellulose or fibrinogen/thrombin solutions can be used to advantage. Alternatively, tissue-coating solutions, such as pectin-containing formulations can be used. Ophthalmic formulation, ear drops, and eye drops are also contemplated as being within the scope of this invention. Additionally, the present invention contemplates the use of transdermal patches, which have the added advantage of providing controlled delivery of an agent to the body. Such dosage forms can be made by dissolving or dispensing the agent in the proper medium. Absorption enhancers can also be used to increase the flux of the agent across the skin. The rate can be controlled by either providing a rate controlling membrane or by dispersing the agent in a polymer matrix or gel.
[0169] Additionally, the carrier for a topical formulation can be in the form of a hydroalcoholic system (e.g., liquids and gels), an anhydrous oil or silicone based system, or an emulsion system, including, but not limited to, oil-in-water, water-in-oil, water-in-oil-in-water, and oil-in-water-in-silicone emulsions. The emulsions can cover a broad range of consistencies including thin lotions (which can also be suitable for spray or aerosol delivery), creamy lotions, light creams, heavy creams, and the like. The emulsions can also include microemulsion systems. Other suitable topical carriers include anhydrous solids and semisolids (such as gels and sticks); and aqueous based mousse systems.
[0170] It will also be appreciated that the compounds of Formula (I) and pharmaceutical compositions thereof can be employed in combination therapies, that is, the compounds and pharmaceutical compositions can be administered concurrently with, prior to, or subsequent to, one or more other desired therapeutics or medical procedures. The particular combination of therapies (therapeutics or procedures) to employ in a combination regimen will take into account compatibility of the desired therapeutics and/or procedures and the desired therapeutic effect to be achieved. It will also be appreciated that the therapies employed may achieve a desired effect for the same disorder, or they may achieve different effects (e.g., control of any adverse effects).
[0171] In still another aspect, the present invention also provides a pharmaceutical pack or kit comprising one or more containers filled with one or more of the ingredients of the pharmaceutical compositions of the present invention, and in certain embodiments, includes an additional approved therapeutic agent for use as a combination therapy. Optionally associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use, or sale of pharmaceutical products, which notice reflects approval by the agency of manufacture, use, or sale for human administration.
EXAMPLES
[0172] In order that the invention described herein may be more fully understood, the following examples are set forth. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this invention in any manner.
Example 1. Preparation of Sample Solutions
Synthesis of the Desferrithiocin (DFT) Analogs
[0173] The desferrithiocin (DFT) analogs and salts thereof useful in the present invention can be prepared from readily available starting materials using methods known in the art. For example, (S)-4′-(HO)-DADFT-norPE (III-A) and (S)-4′-(HO)-DADFT-PE (IV-A) may be synthesized using methods described in International PCT Applications, PCT/US2006/010945, filed Mar. 22, 2006, published as WO 2006/107626, PCT/US2010/002336, filed Aug. 25, 2010, published as WO2011/028255, and U.S. patent application U.S. Ser. No. 11/973,001, filed Oct. 4, 2007, each of which is incorporated herein by reference in its entirety.
Preparation of Sample Solutions Containing Monosodium Salts of the DFT Analogs
[0174] The DFT analogs useful in the inventive methods were converted from the free acid form to the monosodium salt form. Water followed by one equivalent of sodium hydroxide was added to the DFT analog as a free acid. The resulting slurry was vortexed or sonicated until the DFT analog went into solution. More water was added, and the solution was vortexed or sonicated again. The formed yellow solution, having a pH about 7, was used as a sample solution in the following Examples. It is preferred that a fresh sample solution of the DFT analog is made shortly before the solution is used in an assay.
Example 2. Prevention of Acetic Acid-Induced Colitis by Desferrithiocin Analogs in a Rat Model
[0175] Induction of colitis. Male Sprague-Dawley rats (250-350 g) were anesthetized with sodium pentobarbital, 55 mg/kg intraperitoneally. The abdomen was shaved and prepared for surgery. A midline incision was made, and the cecum and proximal colon were exteriorized. A reversible suture was placed at the junction of the cecum and proximal colon. The colon was rinsed with saline (10 ml), and the fluid and intestinal contents were gently expressed out the rectum. A gum-based rectal plug was inserted. The compound of interest, or distilled water in the control animals (2 ml), was injected intracolonically just distal to the ligature. The cecum and proximal colon were returned to the abdominal cavity; the compound was allowed to remain in the gut for 30 min. Then, the cecum and proximal colon were exteriorized again. The rectal plug was removed, and the drug was gently expressed out of the colon. Acetic acid (4%, 2 ml) was injected into the proximal colon over a 15- to 20-sec time period. The acid was allowed to remain in the gut until 1 min had passed (ie, 40-45 sec after the end of the acid administration). The no-acid control rats received distilled water (2 ml), which was administered in the same manner as was the acetic acid. Air (10 ml) was then injected into the proximal colon to expel the acid or water. The cecal/proximal colon ligature was removed, the gut was returned to the abdominal cavity, and the incisions were closed. The animals were allowed to recover overnight and were killed 24 hr later. The entire length of the colon was removed and assessed for damage both densitometrically and biochemically.
[0176] Quantitation of acetic acid-induced colitis. Gross damage was quantitated using Photoshop-based image analysis (version 5.0, Adobe Systems, Mountain View, Calif., USA) on an Apple iMac computer. The Magic Wand tool in the Select menu of Photoshop was used to place the cursor on an area of obvious damage. The tolerance level of the Magic Wand tool was set at 30. The damaged areas were automatically selected by using the Similar command in the Select menu. Then, the Eyedropper tool was used to determine the range of the damage in the highlighted areas. Individual colon images were copied to a blank Photoshop page. The MagicWand tool, with a tolerance set to 100, was used to select all of the pixels in the colon sample. Then, the Histogram tool, which generates a graph in which each vertical line represents the number of pixels associated with a brightness level, was selected in the Image menu. The Red channel was then selected; the darker (damaged areas) appear on the left side of the histogram and the lighter (normal) areas are on the right side. The cursor was then placed on the histogram, the color range determined in an earlier step was selected, and the number of pixels encompassing that range and the percent damage were quantitated automatically.
[0177] Collection of Chelator Tissue Distribution Samples from Rodents. Male Sprague-Dawley rats (250-350 g) were given the chelators orally at a dose of 300 μmol/kg. At times 0.5, 1, 2, 4 and 8 h after dosing (n=3) rats per time point, the animals were euthanized by exposure to CO.sub.2 gas. Blood was obtained via cardiac puncture into vacutainers containing sodium citrate. The blood was centrifuged, and the plasma was separated for analysis. The liver, heart, pancreas, and kidneys were removed from the animals and frozen.
Example 3. Concentration of DFT Analogs in Rat Plasma after PO (Oral) and SC (Subcutaneous) Dose
[0178] Male Sprague-Dawley rats (250-350 g) were given a single s.c. injection or an oral dose of the monosodium salt of deferitin, (S)-4′-(HO)-DADFT-norPE (III-A), or (S)-4′-(HO)-DADFT-PE (IV-A) at a dose of 300 μmol/kg. At times 0.5, 1, 2, 4, and 8 hours (n=3) rats per time point, the animals were euthanized by exposure to C02 gas. Blood was obtained via cardiac puncture into vacutainers containing sodium citrate. The blood was centrifuged, and the plasma was separated for analysis. See
Example 4. Concentration of DFT Analogs in Rat Plasma and Cerebrospinal Fluid after PO (Oral) or SC (Subcutaneous) Dose
[0179] Adult male Sprague-Dawley rats (450-500 g) were used. The rats were not fasted. A sample solution of a monosodium salt of (S)-4′-(HO)-DADFT-norPE (III-A) or (S)-4′-(HO)-DADFT-PE (IV-A) was administered to the rats at an oral or subcutaneous dose of 300 μmol/kg. Concentrations of the DFT analogs in the plasma and cerebrospinal fluid of the rats were measured at 0.5 hour, 1 hour, 2 hours, 4 hours, and 8 hours post administration.
Example 5. Concentration of DFT Analogs in Rat Plasma and Eyes after Subcutaneous Dose
[0180] Rats were not Perfused
[0181] Rats were anesthetized with ketamine/xylazine about 50 minutes after dosing. Blood of the rats was collected via cardiac puncture into vacutainer tubes containing buffered sodium citrate one hour post dose. The rats' eyes were removed. Any extraneous tissue was trimmed and discarded. The eyes were frozen. The entire eye was then processed and assessed for the concentration of the DFT analog. The whole blood was centrifuged, and the plasma was separated and frozen until the concentration of the DFT analog was determined.
Rats were Perfused with Saline
[0182] Rats were anesthetized with ketamine/xylazine about 50 minutes after dosing. Blood of the rats was collected via cardiac puncture into vacutainer tubes containing buffered sodium citrate one hour post dose. The rats' abdomen and thorax were opened, and a portion of the sternum/ribs was removed. A 19-gauge needle was inserted into the left ventricle of the rats, and the right atrium was cut. About 100 ml of saline was perfused transcardially for five minutes. The perfusion was stopped, and the rats' eyes were removed. Any extraneous tissue was trimmed and discarded. The eyes were frozen. The entire eye was then processed and assessed for the concentration of the DFT analog. The whole blood was centrifuged, and the plasma was separated and frozen until the concentration of the DFT analog was determined.
TABLE-US-00001 TABLE 1 Concentration of DFT analogs in the plasma and cerebrospinal fluid of rats treated with the DFT analogs at a PO dose of 300 μmol/kg Concentration Concentration in cerebrospinal DFT Time in plasma fluid analog LogP.sub.app (h) (μM) (μM) IV-A −1.10 0.5 142 ± 57 2.14 ± 1.01 1 64 ± 7 trace 2 32 ± 20 trace 4 2 ± 0.5 trace 8 trace trace III-A −0.89 0.5 424 ± 60 8.07 ± 3.09 1 219 ± 19 5.70 ± 2.74 2 30 ± 5 2.32 (only 1 out 3 animals showed anything) 4 2 ± 0.4 0 ± 0 8 trace 0 ± 0
TABLE-US-00002 TABLE 2 Concentration of DFT analogs in the plasma and eyes of rats treated with the DFT analogs at a SC dose of 300 μmol/kg* Non-perfused Perfused with saline Concen- Concen- tration tration Concen- in the eye Concen- in the eye tration (nmol/g wet tration (nmol/g wet DFT in plasma weight of in plasma weight of analog LogP.sub.app (μM) the eye) (μM) the eye) III-A −0.89 218 ± 16 25.8 ± 6.0 218 ± 51 17.2 ± 5.5 V-A −0.89 701 ± 32 37.8 ± 4.3 663 ± 42 29.7 ± 4.3 *The rats were anesthetized about 50 minutes after dose. The non-perfused rates were killed by exposure to CO.sub.2 one hour post dose. The remaining rats were perfused transcardially one hour post dose with about 100 ml of saline for 5 minutes.
[0183] The foregoing written specification is considered to be sufficient to enable one skilled in the art to practice the present invention. The present invention is not to be limited in scope by the examples provided, since the examples are intended as a single illustration of one aspect of the invention and other functionally equivalent embodiments are within the scope of the invention. Various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description and fall within the scope of the claims. The advantages and objects of the present invention are not necessarily encompassed by each embodiment of the invention.
[0184] All publications, patent applications, and patents mentioned herein are hereby incorporated by reference in their entirety for disclosure of the teachings relevant to the present invention, as if each individual publication, patent application, or patent was specifically and individually indicated to be incorporated by reference. In case of the present specification and a document incorporated by reference including conflicting disclosure, the present specification shall control.