Title: Pharmaceutical nitrones
Abstract: Pharmaceutical nitrone comprise condensates of an N-hydroxylamine and a physiological aldehyde, providing improved delivery and absorption, enhanced stability and reduced toxicity. Preferred physiological aldehydes are subject to endogenous cellular uptake transport, and include pyridoxal, pyridoxal phosphate, and heme-A. Essentially any physiologically compatible and pharmaceutically active hydroxylamine moiety may be incorporated, such as hydroxylamine moieties of prior pharmaceutical nitrones, and known pharmaceutically active hydroxylamines.
Patent Number: 7,026,338 Issued on 04/11/2006 to Ames, et al.
| Inventors:
|
Ames; Bruce N. (Berkeley, CA);
Atamna; Hani (Berkeley, CA)
|
| Assignee:
|
Children's Hospital Research Center at Oakland (Oakland, CA)
|
| Appl. No.:
|
843167 |
| Filed:
|
May 11, 2004 |
| Current U.S. Class: |
514/345; 514/348; 514/410; 546/22; 546/290; 546/296; 548/416 |
| Current Intern'l Class: |
C07D 213/02 (20060101); A61K 31/44 (20060101); A61K 31/39.5 (20060101) |
| Field of Search: |
514/345,348,410
546/22,290,296
548/416
|
References Cited [Referenced By]
U.S. Patent Documents
Primary Examiner: Davis; Zinna Northington
Attorney, Agent or Firm: Osman; Richard Aron
Claims
What is claimed is:
1. A pharmaceutical composition comprising a nitrone of an N-hydroxylamine and
a physiological aldehyde selected from the group consisting of: pyridoxal, pyridoxal
phosphate, and heme-A, or a pharmaceutical salt thereof, and a pharmaceutically
acceptable excipient.
2. The composition of claim 1, wherein the aldehyde is pyridoxal.
3. The composition of claim 1, wherein the aldehyde is pyridoxal phosphate.
4. The composition of claim 1, wherein the aldehyde is heme-A.
5. The composition of claim 1, in an orally administrable effective unit dosage.
6. The composition of claim 1, wherein the N-hydroxylamine is a primary N-hydroxylamine.
7. The composition of claim 1 packaged with a label identifying the N-hydroxylamine
and prescribing a pharmaceutical use thereof, wherein the use comprises reducing
oxidative damage or delaying senescence.
8. A method of making the composition of claim 1, the method comprising condensing
the hydroxylamine and the aldehyde to form the nitrone.
9. A method of using the composition of claim 1, the method comprising administering
or prescribing the composition to a patient determined to be in need thereof.
10. A method of using the composition of claim 1, the method comprising administering
or prescribing the composition to a patient determined to be in need thereof, and
detecting a resultant reduction in oxidative damage or delay of senescence in the patient.
Description
FIELD OF THE INVENTION
The field of the invention is pharmaceutical nitrones of hydroxylamines and physiological
aldehydes, such as pyridoxal.
BACKGROUND OF THE INVENTION
α-Phenyl-N-t-butyl nitrone (PBN) has been shown to
reverse age-related oxidative changes, delay senescence, reverse mitochondrial
decay, and exert a neuroprotective effect after oxidative damage from ischemia/reperfusion
injury. In the course of studying the affect of PBN on cells we observed that old
solutions were more effective than fresh solutions in delaying senescence. This
observation led to our discovery of the anti-senescent effect of the PBN decomposition
product, N-t-butyl hydroxylamine in particular, and N-hydroxylamines in general;
see our U.S. Pat. No.6,455,589.
Our findings indicate that pharmaceutical nitrones can act as prodrugs, liberating
the more biologically active hydroxylamine under physiological conditions. The
present invention provides pharmaceutical nitrones of hydroxylamines and physiologically-preferred aldehydes.
SUMMARY OF THE INVENTION
The invention provides compositions comprising a nitrone of an N-hydroxylamine
and a physiological aldehyde, and related methods, including therapy and manufacture.
The subject compositions include a pharmaceutical compositions comprising a nitrone
of an N-hydroxylamine and a physiological aldehyde, such as pyridoxal (PXAL; Vitamin
B6), pyridoxal phosphate (PLP), and heme-A, or a pharmaceutical salt thereof; and
a pharmaceutically acceptable excipient. Preferred N-hydroxylamines are primary
N-hydroxylamine, and numerous, diverse examples are provided below. The compositions
may be provided in orally administrable effective unit dosages, and/or may be copackaged
with a label identifying the N-hydroxylamine and prescribing a pharmaceutical use
thereof, particularly wherein the use comprises reducing oxidative damage or delaying senescence.
The invention also provides methods of making the subject compositions, particulary
methods comprising condensing the hydroxylamine and the aldehyde to form the nitrone.
The invention also provides methods of using the subject compositions, particularly
methods comprising administering or prescribing the composition to a patient determined
to be in need thereof, and optionally detecting a resultant therapeutic improvement,
particularly a reduction in oxidative damage or delay of senescence in the patient.
DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS OF THE INVENTION
The invention provides compositions comprising a nitrone of an N-hydroxylamine
and a physiological aldehyde, and related methods, including therapy and manufacture.
By incorporating a physiological aldehyde, the subject nitrones can provide a variety
of improvements, including improved delivery and absorption, enhanced stability
and reduced toxicity, as compared with corresponding nitrones incorporating non-physiological
aldehydes, such as benzaldehyde. Preferred physiological aldehydes are subject
to endogenous cellular uptake transport which facilitates delivery. The physiological
aldehyde moiety is derived from natural physiological aldehydes such as pyridoxal
(PXAL; Vitamin B6), pyridoxal phosphate (PLP), and heme-A.
Essentially any physiologically compatible and pharmaceutically active
N-hydroxylamine moiety may be incorporated, such as N-hydroxylamine moieties of
prior pharmaceutical nitrones, and known pharmaceutically active hydroxylamines.
Exemplary hydroxylamine moieties which may be incorporated in the subject nitrones
are found in the prior art nitrones of U.S. Pat. Nos. 6,197,826; 6,310,092; 3,376,540;
6,255,353; 6,342,523; 6,441,032; 6,433,008; 6,509,378; 6,486,349; 6,258,852; 6,083,989;
and 6,545,056; and Publ Nos. US2003/0078297 and US2002/0165274. In particular embodiments,
the hydroxylamine is a primary N-hydroxylamine, such as described in U.S. Pat. No.6,455,589.
In particular embodiments, the composition is a pharmaceutical composition comprising
the nitrone and a pharmaceutically acceptable excipient, which may be provided
in an orally administrable effective unit dosage. The subject compositions may
be administered in various forms, formulations and routes using standard materials
and protocols; see, e.g. Remington's Pharmaceutical Sciences. The compositions
may be packaged with a label identifying the N-hydroxylamine and prescribing a
pharmaceutical use thereof, such as reducing oxidative damage or delaying senescence.
The invention also provides methods of making the subject compositions, e.g.
by condensing the hydroxylamine and the aldehyde to form the nitrone. Exemplary
condensation reaction conditions are shown in Scheme 4 of Durand et al., J. Med.
Chem. 2003, 46, 5230-5237. The N-hydroxylamine moiety is typically prepared by
oxidizing the corresponding amine; see, e.g. U.S. Pat. No.6,455,589; Durand et
al., J. Med. Chem. 2003, 46, 5230-5237, and citations therein.
The invention also provides methods of using the subject compositions, e.g. by
administering or prescribing the composition to a patient determined to be in need
thereof, and optionally detecting a resultant reduction in oxidative damage or
delay of senescence in the patient.
In one embodiment, the subject nitrone if formed by reacting of pyridoxal (PXAL;
Vitamin B6) or pyridoxal phosphate (PLP) (the coenzyme that vitamin B6 is converted
to in the cell ) with a hydroxylamine, such as NtBHA (Schematics 1 & 2). Another
exemplary physiological aldehyde useful for forming the subject condensation products
with hydroxylamines is the aromatic aldehyde containing heme-A (Schematic 3), a
prosthetic group of cytochrome C oxidase (COX) and which is synthesized and utilized
in mitochondria.
##STR1##
##STR2##
Applications
As therapeutics and/or prophylactics, the nitrones of this invention are useful
for treating a wide variety of medical dysfunctions and diseases, particularly
in human patients. Among the various medical conditions which may be prevented
and/or treated, the subject nitrones are particularly useful for treating conditions
involving acute oxidate damage, such as acute intense oxidative damage to a region
of the central nervous system, e.g. stroke, conditions associated with stroke,
concussion and subarachnoid hemorrhage or chronic oxidate damage, such as is associated
with senescence and aging. Accordingly, the subject compositions are useful in
treating a variety of dysfunctions or disorders characterized by oxidized proteins,
nucleic acids or lipids in the tissues, cells, or associated fluids (such as the
blood). Cellular, tissue, systemic and organismal indicia of oxidative damage are
known in the art and exemplified below; for example, in vitro cellular oxidative
damage and senescence may be measured as described in Chen et al. (1995) Proc.
Natl. Acad. Sci. USA 92, 4337-4341.
Applicable target disorders are generally divided into disorders of the
central and peripheral nervous system and disorders of the peripheral organs. Disorders
of the CNS include stroke, aging, neurodegenerative conditions, such as Alzheimer's
disease, Parkinsonism, concussion, aneurysm, ventricular hemorrhage and associated
vasospasm, migraine and other vascular headaches, spinal cord trauma, neuroanesthesia
adjunct, HIV-dementia and the like. Disorders of the peripheral nervous system
include diabetic peripheral neuropathy and traumatic nerve damage. Peripheral organ
disease includes atherosclerosis (both diabetic and spontaneous), chronic obstructive
pulmonary disease (COPD), pancreatitis, pulmonary fibrosis due to chemotherapeutic
agents, angioplasty, trauma, burns, ischemic bowel disease, wounds, ulcers and
bed sores, lupus, ulcerative colitis, organ transplantation, renal hypertension,
overexertion of skeletal muscle, epistaxis (pulmonary bleeding), autoimmune conditions,
such as systemic lupus (erythematosus), multiple sclerosis and the like; and inflammatory
conditions, such as inflammatory bowel disease, rheumatoid arthritis, septic shock,
erythema nodosum leprosy, septicemia, uveitis, and the like. Some disease conditions
may be classified as, for example, both autoimmune and inflammatory conditions,
such as multiple sclerosis and the like.
Other conditions associated: with excessive oxidation of proteins or lipids
that can be treated include undesirable or altered oxidation of low density lipoprotein;
and dysfunction from exposure to radiation, including x-ray, ultraviolet, gamma
and beta radiation, and cytotoxic compounds, including those used for chemotherapy
for cancer and viral infections.
Accordingly, in one aspect, the invention provides a method for treating
a patient with an acute central nervous system disorder, said method comprising
administering to said patient a pharmaceutical composition comprising a pharmaceutically
acceptable carrier and an effective acute central nervous system disorder-treating
subject nitrone. In a preferred embodiment of this method, the acute central nervous
system disorder treated is stroke.
In another aspect, the invention provides a method for treating a patient with
an acute cardiovascular disorder, said method comprising administering to said
patient a pharmaceutical composition comprising a pharmaceutically acceptable carrier
and an effective acute cardiovascular disorder-treating amount of a subject nitrone.
In a preferred embodiment of this method, the acute cardiovascular disorder treated
is cardiac infarction.
In still another aspect, the invention is directed to a method for treating a
patient with a neurodegenerative disease which method comprises administering to
said patient a pharmaceutical composition comprising a pharmaceutically acceptable
carrier and an effective neurodegenerative disease-treating amount of a subject
nitrone. Additionally, the invention is directed to a method for preventing the
onset of a neurodegenerative disease in a patient at risk for developing the neurodegenerative
disease which method comprises administering to said patient a pharmaceutical composition
comprising a pharmaceutically acceptable carrier and an effective neurodegenerative
disease-preventing amount of a subject nitrone. In preferred embodiments of this
invention, the neurodegenerative disease treated and/or prevented in the above
methods is Alzheimer's disease, Parkinson's disease, HIV dementia, a dopamine-associated
neurodegenerative condition and the like.
In yet another aspect, the invention is directed to a method for treating a patient
with an autoimmune disease which method comprises administering to said patient
a pharmaceutical composition comprising a pharmaceutically acceptable carrier and
an effective autoimmune disease-treating amount of a subject nitrone. The invention
is also directed to a method for preventing the onset of an autoimmune disease
in a patient at risk for developing the autoimmune disease which method comprises
administering to said patient a pharmaceutical composition comprising a pharmaceutically
acceptable carrier and an effective autoimmune disease-preventing amount of a subject
nitrone. In preferred embodiments of this invention, the autoimmune disease treated
and/or prevented in the above methods is systemic lupus, multiple sclerosis and
the like.
In still another aspect, the invention is directed to a method for treating a
patient with an inflammatory disease which method comprises administering to said
patient a pharmaceutical composition comprising a pharmaceutically acceptable carrier
and an effective inflammatory disease-treating amount of a subject nitrone. Additionally,
the invention is directed to a method for preventing the onset of an inflammatory
disease in a patient at risk for developing the inflammatory disease which method
comprises administering to said patient a pharmaceutical composition comprising
a pharmaceutically acceptable carrier and an effective inflammatory disease-preventing
amount of a subject nitrone. In preferred embodiments of this invention, the inflammatory
disease treated and/or prevented in the above methods is rheumatoid arthritis,
septic shock, erythema nodosum leprosy, septicemia, uveitis and the like.
In another aspect the invention provides a method for treating a patient suffering
from a condition characterized by progressive loss of nervous system function due
to mitochondrial dysfunction. This method involves administering to the patient
with loss of central nervous system function an effective amount of one or more
of the pharmaceutical compositions described herein.
In each aspect, the invention may be implemented by a first diagnostic step,
e.g.
determining that the patient is suffering from, subject to, or predisposed to a
target disease or condition followed by prescribing and/or administering to the
patient a subject nitrone composition, optionally followed by a evaluation/confirmation/prognosis
step, e.g. determining an effect of the treatment, such as an amelioration of symptom
of a targeted disease or condition or an indicator thereof.
Administration
The subject compositions may be formulated for administration by any route, including
without limitation, oral, buccal, sublingual, rectal, parenteral, topical, inhalational,
including itnranasal, injectable, including subcutaneous, intravenous, intramuscular,
etc., topical, including transdermal, etc. The subject compositions are administered
in a pharmaceutically (including therapeutically, prophylactically and diagnostically)
effective amount. The amount of the compound actually administered will typically
be determined by a physician, in the light of the relevant circumstances, including
the condition to be treated, the chosen route of administration, the actual compound
administered, the age, weight, and response of the individual patient, the severity
of the patient's symptoms, and the like.
Intravenous dose levels for treating acute medical conditions range from
about 0.1 mg/kg/hour to at least 10 mg/kg/hour over a period of from about 1 to
about 120 hours and especially 24 to 96 hours. Preferably, an amount of at least
about 0.2 mg/kg/hour is administered to the patient. A preloading bolus of from
about 10 mg to about 500 mg may also be administered to achieve adequate steady
state levels. While intravenous administration is preferred for acute treatments,
other forms of parenteral administration, such as intramuscular injection can be
used, as well. In such cases, dose levels similar to those described above may
be employed.
Another acute condition which can be advantageously treated with the nitrones
of this invention is acute oxidative damage to the cardiovascular system, such
as the damage which occurs in a patient who has suffered a cardiac infarction or
the like. When treating such a condition, a pharmaceutical composition comprising
a subject nitrone is administered parenterally, e.g. intravenously, at doses similar
to those described above for stroke and other acute CNS conditions.
As discussed above, the compounds described herein are suitable for use in a
variety
of drug delivery systems. Injection dose levels for treating neurodegenerative,
autoimmune and inflammatory conditions range from about 0.1 mg/kg/hour to at least
10 mg/kg/hour, all for from about 1 to about 120 hours and especially 24 to 96
hours. A preloading bolus of from about 0.1 mg/kg to about 10 mg/kg or more may
also be administered to achieve adequate steady state levels. The maximum total
dose is not expected to exceed about 2 g/day for a 40 to 80 kg human patient.
For the prevention and/or treatment of long-term conditions, such as neurodegenerative
and autoimmune conditions, the regimen for treatment usually stretches over many
months or years so oral dosing is preferred for patient convenience and tolerance.
With oral dosing, one to five and especially two to four and typically three oral
doses per day are representative regimens. Using these dosing patterns, each dose
provides from about 0.02 to about 50 mg/kg of nitrone, with preferred doses each
providing from about 0.04 to about 30 mg/kg and especially about 1 to about 10 mg/kg.
When used to prevent the onset of a degenerative condition, such as a neurodegenerative,
autoimmune or inflammatory condition, the nitrone compositions of the invention
will be administered to a patient at risk for developing the condition, typically
on the advice and under the supervision of a physician, at the dosage levels described
above. Patients at risk for developing a particular condition generally include
those that have a family history of the condition, or those who have been identified
by genetic testing or screening to be particularly susceptible to developing the
condition. When used prophylactically, the subject pharmaceutical compositions
are administered orally to the predisposed patient. The doses for this oral therapy
will typically be derived from those set forth above for treating persons suffering
from the neurodegenerative, autoimmune or inflammatory condition.
The compounds of this invention can be administered as the sole active agent
or they can be administered in combination with other agents, including other active
nitrones or hydroxylamine compounds.
EXAMPLES
The following formulation examples illustrate representative pharmaceutical compositions
of this invention. The present invention, however, is not limited to the following
exemplified pharmaceutical compositions.
Formulation 1—Tablets: The nitrone of NtBHA and pyridoxal is admixed
as a dry powder with a dry gelatin binder in an approximate 1:2 weight ratio. A
minor amount of magnesium stearate is added as a lubricant. The mixture is formed
into 240-270 mg tablets (80-90 mg of active nitrone compound per tablet) in a tablet press.
Formulation 2—Tablets: The nitrone of N-benzylhydroxylamine and
pyridoxal is admixed as a dry powder with a dry gelatin binder in an approximate
1:2 weight ratio. A minor amount of magnesium stearate is added as a lubricant.
The mixture is formed into 240-270 mg tablets (80-90 mg of active nitrone compound
per tablet) in a tablet press.
Formulation 3—Capsules: The nitrone of N-(n-nitrobenzyl)hydroxylamine
and pyridoxal 5-phosphate is admixed as a dry powder with a starch diluent in an
approximate 1:1 weight ratio. The mixture is filled into 250 mg capsules (125 mg
of active nitrone compound per capsule).
Formulation 4—Capsules: The nitrone of N-(hydroxymethyl)hydroxylamine
and pyridoxal 5-phosphate is admixed as a dry powder with a starch diluent in an
approximate 1:1 weight ratio. The mixture is filled into 250 mg capsules (125 mg
of active nitrone compound per capsule).
Formulation 5—Liquid: The nitrone of N-(acetyloxymethyl)hydroxylamine
and Heme-A (50 mg), sucrose (1.75 g) and xanthan gum (4 mg) are blended, passed
through a No. 10 mesh U.S. sieve, and then mixed with a previously made solution
of microcrystalline cellulose and sodium carboxymethyl cellulose (11:89, 50 mg)
in water. Sodium benzoate (10 mg), flavor, and color are diluted with water and
added with stirring. Sufficient water is then added to produce a total volume of
5 ml.
Formulation 6—Liquid: The nitrone of N-aminomethylhydroxylamine
and Heme-A (50 mg), sucrose (1.75 g) and xanthan gum (4 mg) are blended, passed
through a No. 10 mesh U.S. sieve, and then mixed with a previously made solution
of microcrystalline cellulose and sodium carboxymethyl cellulose (11:89, 50 mg)
in water. Sodium benzoate (10 mg), flavor, and color are diluted with water and
added with stirring. Sufficient water is then added to produce a total volume of
5 ml.
Formulation 7—Injection: The nitrone of 1-hydroxylamine-butane-4-sulfonic
acid and pyridoxal is dissolved in a buffered sterile saline injectable aqueous
medium to a concentration of approximately 5 mg/ml.
Formulation 8—Injection: The nitrone of N-(2-nitroethyl)hydroxylamine
and pyridoxal is dissolved in a buffered sterile saline injectable aqueous medium
to a concentration of approximately 5 mg/ml.
The foregoing detailed description and examples are offered to illustrate this
invention and are not to be construed in any way as limiting the scope of this invention.
All publications and patent applications cited in this specification and all
references cited therein are herein incorporated by reference as if each individual
publication or patent application or reference were specifically and individually
indicated to be incorporated by reference. Although the foregoing invention has
been described in some detail by way of illustration and example for purposes of
clarity of understanding, it will be readily apparent to those of ordinary skill
in the art in light of the teachings of this invention that certain changes and
modifications may be made thereto without departing from the spirit or scope of
the appended claims.
*
