WO2005027887A2

WO2005027887A2 - Methods and compositions for improving endothelial function

Info

Publication number: WO2005027887A2
Application number: PCT/US2004/030587
Authority: WO
Inventors: Alan M. Ezrin; Alan Moore; Gregory N. Beatch; Lewis S. L. Choi; Thomas Munzel; Stephan Baldus
Original assignee: Cardimone Pharma Corporation
Priority date: 2003-09-17
Filing date: 2004-09-17
Publication date: 2005-03-31
Also published as: WO2005027887A3

Abstract

The invention relates to methods, compositions, and uses for improving impaired endothelial function associated with vascular disease. More particularly the invention relates to methods, compositions and uses comprising xanthine oxidase inhibitors to treat and/or prevent coronary artery disease or coronary heart disease, and related diseases or conditions.

Description

TITLE: Methods and Compositions for Improving Endothelial Function FIELD OF THE INVENTION The invention relates to methods, compositions, and uses for improving endothelial function in coronary heart disease (CHD) or coronary artery disease (CAD) and related cardiac disorders. More particularly the invention relates to methods, compositions and uses comprising xanthine oxidase inhibitors to treat and/or prevent coronary artery disease or coronary heart disease, and related cardiac disorders. BACKGROUND OF THE INVENTION The pathophysiology underlying coronary artery disease (CAD) has been firmly linked to reduced bioavailabihty of endothelial-derived nitric oxide (NO) (1). Nitric oxide, constitutively synthesized by endothelial cells, not only prevents leukocyte and platelet aggregation, smooth muscle proliferation and lipid oxidation, but also elicits potent vasodilatory properties by activating smooth muscle cell guanylate cyclase (2). Vascular NO bioavailabihty is under exquisite control of vessel wall generated free radicals, with oxidant- producing, enzyme-mediated consumption of NO by superoxide and hydrogen peroxide-dependent mechanisms been viewed as one of the principal mechanisms accounting for endothelial dysfunction (3, 4). Whereas the chemical reactions responsible for NO catabolism are well characterized the biologically relevant sources for superoxide in CAD remain to be defined. Multiple vascular superoxide and hydrogen peroxide generating systems have been identified, such as the phagocytic and vascular NADPH oxidase and its homologues, uncoupled endothelial NO synthase, mitochondria, platelets, and xanthine oxidase (XO), respectively (5-10). Xanthine oxidase, a molybdopterin-containing flavoprotein, displays increased circulating levels and both readily binds to and is expressed by vascular endothelium in a variety of inflammatory diseases. At this site critical for NO-dependent signaling, XO can generate superoxide and hydrogen peroxide upon purine oxidation (11). Experimental studies in hypercholersterolemic rabbits have demonstrated that oxypurinol improves endothelium-dependent vasodilation by reducing vascular steady state superoxide levels. In clinical studies, allopurinol and its metabolite oxypurinol improved forearm blood flow in smokers, patients with dilated cardiomyopathy, diabetes mellitus and hypercholesterolemia (14-17). The citation of any reference herein is not an admission that such reference is available as prior art to the instant invention. SUMMARY OF THE INVENTION Applicants have demonstrated that xanthine oxidase-derived reactive species contribute to coronary and peripheral endothelial dysfunction. In particular, they found that xanthine oxidase derived reactive species catalyze NO catabolism in the coronary circulation, and inhibition of xanthine oxidase increased vascular NO bioavailabihty that improves endothelial function and profoundly increases cardiac perfusion. Xanthine oxidase was also considered to be distributed in the microcirculation. Therefore, the present invention contemplates a method for improving coronary and peripheral endothelial function in a patient. The method can comprise inhibiting production or activity of, or reducing the amount of xanthine oxidase-derived reactive species in coronary and/or peripheral vasculature in the patient. Endothelial function may be impaired as the direct or indirect result of one or more of xanthine oxidase (XO)-derived reactive oxygen species, NO catabolism, and altered NO-dependent signalling. The invention also relates to a method of preventing and/or treating a vascular and/or cardiovascular disease or dysfunction, in particular coronary heart disease or coronary artery disease, in a patient comprising inhibiting production or activity of, or reducing the amount of xanthine oxidase-derived reactive species in coronary and/or peripheral vasculature in the patient. Reduction of xanthine oxidase-derived reactive species can affect enzymes that are dependent on the reactive species. In particular, xanthine oxidase-derived reactive species can affect superoxide and hydrogen peroxide dependent oxidizing enzymes. For example, xanthine oxidase-derived reactive species can inhibit leukocyte myeloperoxidase. Therefore the invention contemplates a method for modulating (e.g. enhancing) the activity of an enzyme dependent on xanthine oxidase-derived reactive species, in particular leukocyte myeloperoxidase, comprising directly or indirectly inhibiting production or activity of, or reducing the amount of xanthine oxidase-derived reactive species. In embodiments of the methods of the invention the xanthine oxidase-derived reactive species are superoxide,¹ hydrogen peroxide, and/or peroxynitrite. In other embodiments of the methods of the invention, xanthine oxidase-derived reactive species are inhibited or reduced in the coronary vasculature. In further embodiments of the methods of the invention, inhibition or reduction of xanthine oxidase- derived reactive species may be achieved by inhibiting xanthine oxidase, in particular by using a xanthine oxidase inhibitor. In a particular embodiment, the xanthine oxidase inhibitor substantially inhibits one or both of free xanthine oxidase and bound xanthine oxidase. A xanthine oxidase inhibitor may be present in a concentration or dose sufficient to increase NO signalling, decrease NO catabolism, or inhibit or reduce the amount of xanthine oxidase-derived reactive species. In another embodiment, the concentration or dose results in increased NO signalling, decreased NO catabolism, and increased hypoxanthine levels. The invention provides a method for increasing bioavailabihty of endothelial derived vascular NO comprising inhibiting the production or function of, or reducing the amount of, xanthine oxidase derived- reactive species in the coronary vasculature. The invention relates to a method for reducing NO catabolism in the coronary vasculature comprising inhibiting the production or function of, or reducing the amount of, xanthine oxidase-derived reactive species, in the coronary vasculature. Still further the invention contemplates a method for inhibiting catalytic NO catabolism in a vascular region that is necessary for, or requires NO for NO-dependent vascular relaxation comprising inhibiting the production of, or reducing the amount of, xanthine oxidase-derived reactive species, in the region. The invention also relates to a method for increasing NO-signalling in the coronary vasculature comprising inhibiting the production or function of, or reducing the amount of, xanthine oxidase-derived reactive species. The invention also relates to a method of preventing and/or treating a coronary artery disease in a patient comprising administering an agent that enhances NO-dependent signalling in the coronary and/or peripheral vasculature. In an aspect, the agent enhances the NO-dependent signalling in the coronary vasculature. The invention also relates to a method of preventing and/or treating coronary artery disease in a patient comprising administering an agent that inhibits NO catabolism in a vascular region that requires NO for NO-dependent vascular relaxation. In an aspect, the agent inhibits NO catabolism in the coronary vasculature. The invention also relates to a method of preventing and/or treating a cardiovascular disease associated with impaired endothelial function in a patient comprising administering an agent that inhibits the production or function of, or reduces the amount of, reactive species, in particular xanthine oxidase-derived reactive species. In an aspect, the agent inhibits or reduces xanthine oxidase-derived reactive species in the coronary vasculature. The present invention contemplates a method for preventing and/or treating a coronary heart disease, coronary artery disease, coronary artery dysfunction, or coronary endothelial dysfunction, in a patient comprising administering an agent that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived reactive species in the coronary vasculature. ¹ The present invention also contemplates a method for preventing and/or treating a cardiovascular disease with impaired cardiac blood flow, in particular impaired coronary artery blood flow or reduced coronary artery diameter, in a patient comprising administering an agent that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived reactive species in the coronary vasculature. The present invention further contemplates a method for restoring ability of the coronary and/or peripheral artery (e.g. brachial artery) to increase in diameter in a patient comprising administering an agent that enhances NO-dependent signalling in the coronary and/or peripheral vasculature, inhibits NO catabolism in the coronary and/or peripheral vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived oxygen species in the coronary and/or peripheral vasculature. In a particular embodiment, the invention provides a method for improving flow-dependent vasodilation of the coronary artery in a patient comprising administering an agent that enhances NO- dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived oxygen species in the coronary vasculature In another particular embodiment, the invention provides a method for improving flow-dependent vasodilation of the peripheral artery (e.g. brachial artery) in a patient comprising administering an agent that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived oxygen species in the coronary vasculature The invention contemplates a method for restoring the ability of the coronary artery to increase in diameter in a patient comprising administering an agent that that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived oxygen species in the coronary vasculature. In embodiments of the methods of the invention, the coronary vasculature is the coronary microcirculation. In embodiments of methods of the invention, the agent is a xanthine oxidase inhibitor, in particular oxypurinol. The present invention relates to the use of a xanthine oxidase inhibitor (XOI) to treat and/or prevent coronary heart disease (CHD) or coronary artery disease (CAD) in a patient, such as mammal, particularly a primate such as a human. In one aspect, the present invention provides methods for treatment and/or prevention of coronary heart disease (CHD) or coronary artery disease (CAD) in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. In an embodiment patients are selected for treatment that are suffering from, susceptible to, or that have suffered coronary artery disease, where a reduction in xanthine oxidase-derived oxygen species or improved NO bioavailabihty is an intended desired therapy. The invention also provides a method for treating coronary heart disease in a mammal suffering from, susceptible to, or that has suffered coronary heart disease, comprising selecting a mammal for treatment of coronary heart disease that is suffering from or susceptible to coronary heart disease and administering to the selected mammal a composition comprising an effective amount of a xanthine oxidase inhibitor. The invention also provides a method for treating coronary artery disease in a mammal suffering from, susceptible to, or that has suffered coronary artery disease, comprising selecting a mammal for treatment of coronary artery disease that is suffering from or susceptible to coronary artery disease and administering to the selected mammal a composition comprising an effective amount of a xanthine oxidase inhibitor. In an aspect of the invention, a method is provided for treating coronary heart disease in a mammal suffering from, susceptible to, or that has suffered coronary heart disease comprising administering to the mammal a composition comprising a therapeutically effective amount of allopurinol or oxypurinol. In another aspect of the invention, a method is provided for treating coronary artery disease in a mammal suffering from, susceptible to, or that has suffered coronary artery disease comprising administering to the mammal a composition comprising a therapeutically effective amount of allopurinol or oxypurinol. In another aspect of the invention, a method is provided for treating heart failure in a mammal suffering from, susceptible to, or that has suffered coronary artery disease comprising administering to the mammal a composition comprising a therapeutically effective amount of oxypurinol. In a further aspect, the present invention provides methods for treatment and/or prevention of coronary artery dysfunction in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. In an embodiment, the coronary artery dysfunction is due to heart disease. In another embodiment, the coronary artery dysfunction is impaired cardiac blood flow. In a further aspect, the present invention provides methods for improving cardiac blood flow, more particularly coronary artery blood flow in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. In a further aspect, the present invention provides methods for improving endothelium-dependent vasodilation in a patient comprising reducing vascular steady state superoxide levels by administering an effective amount of a xanthine oxidase inhibitor, in particular oxypurinol. In a further aspect the invention provides methods for attenuating vasomotor dysfunction within the coronary circulation of a patient comprising administering an effective amount of a xanthine oxidase inhibitor, in particular oxypurinol. In another aspect, the present invention provides methods for increasing coronary artery diameter in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. Coronary arterty diameter can be measured by angiography or morphometric measures. In a further aspect, the present invention provides methods for restoration of the ability of the coronary artery to increase in diameter size in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. Restoration of the ability of the coronary artery to increase in diameter size can be measured by one or more of the following: (a) angiography or morphometric measures; (b) improved cardiac blood flow; (c) improved coronary artery blood flow; and (d) improved cardiac blood flow or coronary artery blood flow as assessed by standard methods of blood flow measurements; for example, dye dilution techniques, doppler flow, ultrasound or other standard measures of blood flow. In another aspect, the present invention provides methods for treatment and/or prevention of impaired cardiac blood flow in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. In another aspect, the present invention provides methods for normalization of vascular and/or cardiovascular function in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. Normalization of vascular and/or cardiovascular function can be measured by improved blood flow in a patient. Normalization of vascular and/or cardiovascular function in a patient could lead to improvement in cardiac and/or heart functions in general in a patient. In particular, it could lead to an improvement in cardiac and/or heart functions such as heart rate, heart rhythm and cardiac contraction. The invention also provides a method of normalizing abnormal levels of enzymes and/or other bio- markers indicative of heart disease comprising administering an effective amount of a xanthine oxidase inhibitor. In an embodiment, the enzymes are dependent on reactive species such as xanthine oxidase- derived reactive species. In a particular embodiment, the enzymes are hydrogen peroxide dependent NO- oxidizing enzymes including but not limited to leukocyte myeloperoxidase. In another aspect, the present invention provides methods for treatment and/or prevention of chest pain (e.g. angina) in a patient, such as a mammal, particularly a primate such as a human, comprising administering to the patient an effective amount of a xanthine oxidase inhibitor. In an embodiment, the chest pain (e.g. angina) is due to heart disease. In another embodiment, the chest pain (e.g. angina) is due to coronary artery dysfunction, more particularly impaired cardiac blood flow. In a further embodiment, the chest pain is due to vascular dysfunction, more particular cardiovascular dysfunction. In a still further embodiment, the chest pain is due to vascular and/or cardiovascular dysfunction such as impaired vascular and/or cardiovascular blood flow. The invention provides a pharmaceutical composition comprising a xanthine oxidase inhibitor in an effective amount to provide a beneficial effect to prevent and/or treat a vascular disease associated with xanthine oxidase-derived reactive species, and a pharmaceutically acceptable carrier, excipient, vehicle, or diluent. In an aspect the invention provides a composition comprising a xanthine oxidase inhibitor in an effective amount to prevent and/or treat coronary heart disease and related diseases associated with xanthine oxidase-derived reactive species in the coronary circulation, in particular the coronary microcirculation, and a pharmaceutically acceptable carrier, excipient, vehicle, or diluent. In an embodiment, the invention provides a composition comprising a xanthine oxidase inhibitor in a concentration or dose sufficient to increase NO signalling, decrease NO catabolism, or inhibit or reduce the amount of xanthine oxidase-derived species in coronary vasculature, in particular coronary microcirculation. In another embodiment, the concentration or dose results in increased NO signalling, decreased NO catabolism, and increased hypoxanthine levels. In embodiments of the invention, the xanthine oxidase inhibitor in a composition of the invention is oxypurinol. The invention contemplates a pharmaceutical composition for preventing and/or treating a condition and/or disease ' described herein comprising two or more of a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more agent that improves NO bioavailabihty. In an embodiment, the invention provides a method for preparing a pharmaceutical composition comprising mixing an effective amount of a xanthine oxidase inhibitor (e.g. allopurinol or oxypurinol), and optionally an agent that improves NO bioavailabihty and a pharmaceutically acceptable carrier, excipient, vehicle, or diluent. The invention also relates to a combination therapy for treating and/or preventing coronary heart disease or coronary artery disease, coronary artery dysfunction, or coronary endothelial dysfunction comprising administering to a patient two or more of a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more agent that improves NO bioavailabihty. In an aspect, the glycosaminoglycan is heparin. In a further aspect, an agent that improves NO bioavailabihty is an ACE inhibitor or a HMG CoA reductase inhibitor. A combination therapy may also comprise an Angiotensin Receptor Blocker. The invention also relates to a kit for carrying out a method of the invention. The invention further relates to a pharmaceutical pack or kit comprising one or more containers filled with one or more of the ingredients of a method or pharmaceutical composition of the invention. Associated with such container(s) can be various written materials such as instructions for use, or a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, which notice reflects approval by the agency of manufacture, use, or sale for human or veterinary administration. These and other aspects, features, and advantages of the present invention should be apparent to those skilled in the art from the following drawings and detailed description. DESCRIPTION OF THE DRAWINGS The present invention will now be described only by way of example, in which reference will be made to the following Figures: Figure 1. This figure shows oxypurinol's relief of acetylcholine-mediated constriction of coronary arteries (LAD or Cfx) from patients with endothelial dysfunction (n = 13). As can be seen in the graph, acetylcholine (0.1 [Ach-1], 1.0 [Ach-2], and 10 [Ach-3] micromolar, infused for 3 minutes into the target artery) dose dependently constricts the coronary arteries in these patients. Oxypurinol (13.4 mg/min, intravenously infused for 15 min at 1 mL/min), significantly reverses the vasoconstriction caused by acetylcholine challenge (p < 0.05); pre - refers to measured results before infusion of oxypurinol; post - refers to measured results after infusion of oxypurinol Figure 2. This figure shows the increase in coronary artery (LAD or Cfx) flow velocity produced by oxypurinol during acetylcholine challenge in patients with endothelial dysfunction (n = 13). As can be seen in the graph, acetylcholine (0.1 [Ach-1], 1.0 [Ach-2], and 10 [Ach-3] micromolar infused for 3 minutes into the target artery) dose dependently decreases flow velocity in the coronary arteries in these patients. Oxypurinol (13.4 mg/min, intravenously infused for 15 min at 1 mL/min) significantly reverses the decrease in flow velocity caused by acetylcholine challenge (p < 0.05); pre - refers to measured flow velocity before infusion of oxypurinol; post - refers to measured flow velocity after infusion of oxypurinol. Figure 3. Schematic outline of the study design. Patients, who had undergone either diagnostic angiography or angioplasty, received incremental doses of intracoronary acetylcholine (ACh; 2 minutes infusion time). At each concentration, lumen diameter (QCA) and average peak velocity (APV) assessed by doppler flow wire were recorded. Subsequently, patients received oxypurinol (200mg; i.v.) and the ACh challenge was repeated. Intracoronary administration of nitroglycerine (NTG, 200μg) completed the study. Plasma was sampled before and after oxypurinol infusion. In 8 consecutive patients, non-invasive testing of forearm endothelial function by flow-mediated dilation (FMD) of the brachial artery was performed before and immediately after the catheterization procedure. The 30 day follow up was performed by telephone contact. Figure 4. Analysis of plasma xanthine oxidase activity. Following oxypurinol, xanthine oxidase activity decreased by 63% from 0.051 ± 0.001 to 0.019 ± 0.005 μU/mg protein (p<0.01). Data from 20 patients are presented as mean±SEM. Figure 5. Changes in minimal coronary lumen diameter and coronary blood flow following oxypurinol administration. Out of the 18 patients, who completed the protocol, 5 patients, revealed coronary vasodilation at the highest dose of ACh administered (group I), whereas 13 patients, responded by vasoconstriction (group II). (a) Minimal luminal diameter (MLD) in patients of group I. Changes in MLD as compared to baseline did not differ with oxypurinol (2.8±4.2 vs. 5.2±0.7% at ACh 10^"5μM, p>0.05). (b) Also, the increase in coronary blood flow did not differ significantly before and after oxypurinol administration (135±75 vs 154±61% at ACh 10^"5μM, p>0.05). (c) In contrast, oxypurinol attenuated the ACh-dependent decrease in MLD in patients of group II (-23±4 vs -15±4% at ACh 10^"5μ , p<0.05). (d) Also, coronary blood flow increased significantly following oxypurinol infusion (16±17% vs 62±18% at ACh lO^"sμM, p<0.05). Figure 6. Non-invasive assessment of endothelial function in response to oxypurinol. Flow- mediated dilation of the brachial artery was measured before coronary procedure and immediately after the coronary intervention in 8 consecutive patients. Forearm mediated dilation significantly increased following acute oxypurinol treatment (5.1±1.5 vs 7.6±1.5%, p<0.01). DETAILED DESCRIPTION OF THE INVENTION The general terms used herein have the following meanings within the scope of the present invention. It is to be understood that the recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.90, 4, and 5). It is also to be understood that all numbers and fractions thereof are presumed to be modified by the term "about." Further, it is to be understood that "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a composition containing "a compound" includes a mixture of two or more compounds. The term "about" means plus or minus 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10% of the number to which reference is being made. For the prophylaxis and/or treatment of the conditions and/or diseases referred to herein, the compounds useful in the compositions and methods of the present invention can be used as pharmaceutically acceptable salts. Pharmaceutically acceptable salts include but are not limited to compounds of the present invention derived from inorganic acids, such as hydrochloric, hydrobromic, phosphoric, metaphosphoric, nitric, sulfonic, and sulfuric acids, and organic acids such as acetic, benzenesulfonic, benzoic, citric, ethanesulfonic, fumaric, gluconic, glycolic, isothionic, lactic, lactobionic, maleic, malic, methanesulfonic, succinic, toluenesulfonic, tartaric, and trifluoroacetic acids. Suitable pharmaceutically acceptable base salts include ammonium salts, alkali metal salts such as sodium and potassium salts, and alkaline earth salts such as magnesium and calcium salts. Some of the compounds described herein contain one or more asymmetric centers and may give rise to enantiomers, diasteriomers, and other stereoisomeric forms which may be defined in terms of absolute stereochemistry as (R)- or (S)-. The present invention is meant to include all such possible diasteriomers and enantiomers as well as their racemic and optically pure forms. Optically active (R)- and (S)-isomers may be prepared using chiral synthons or chiral reagents, or resolved using conventional techniques. When the compounds described herein contain centers of geometric asymmetry, and unless specified otherwise, it is intended that the compounds include both E and A geometric isomers. All tautomeric forms are intended to be included within the scope of the invention. "Catabolism" generally refers to a degradative metabolic process in cells, in particular processes by which organisms convert substances into excreted compounds. "Effective amount" relates to a dose of the substance that will lead to the desired pharmacological and/or therapeutic effect. The desired pharmacological effect is, to alleviate a condition or disease described herein, or symptoms associated therewith. A desired effect may be a beneficial effect described herein. In particular, a desired effect may be one or more of the following: reduced or suppressed xanthine oxidase- derived reactive species, improved NO bioavailabihty, increased NO-dependent signalling in the coronary vasculature, decreased NO catabolism in the coronary vasculature, improved endothelial function, restored ability of the coronary artery to increase in diameter, improved coronary artery blood flow, improved endothelium-dependent vasodilation, attenuated vasomotor dysfunction, normalized vascular function, and/or, normalized levels of enzymes and other biomarkers of coronary artery disease. An effective amount of a substance may vary according to factors such as the disease state, age, sex, and weight of the individual, and the ability of the substance to elicit a desired response in the individual. Dosage regimen may be adjusted to provide the optimum therapeutic response. For example, several divided doses may be administered daily or the dose may be proportionally reduced as indicated by the exigencies of the therapeutic situation. The terms "patient" "subject", or "individual" refer to an animal including a warm-blooded animal such as a mammal, which is afflicted with or suspected of having or being pre-disposed to a condition or disease as described herein. In particular, the terms refer to a human. The terms also include domestic animals bred for food or as pets, including horses, cows, sheep, poultry, fish, pigs, cats, dogs, and zoo animals. In embodiments of the invention, the patient is a mammal, particularly a primate such as a human. The methods herein for use on subjects/individuals/patients contemplate prophylactic as well as therapeutic or curative use. Typical subjects for treatment include persons susceptible to, suffering from or that have suffered a condition or disease described herein. In embodiments of the invention, patients have impaired coronary endothelial function. In particular, suitable subjects for treatment in accordance with the invention include persons that are susceptible to, suffering from or that have inflammatory vascular disease, more particularly cardiovascular disease, most particularly coronary artery disease. More particularly, patients have angiographically-documented coronary artery disease, preserved left ventricular function and physiologic uric acid levels. In an aspect, a subject may be selected based on one or more of the following inclusion criteria. a) Angiographically documented coronary heart disease. In particular documented coronary heart disease with generalized wall changes (stenosis <40%) and/or existence of a significant lesion with the indication for percutaneous primary intervention in one or two coronary artery branches. b) Existence of a coronary artery that is not occluded according to angiography and has only minimal lesions (stenosis <40%); this artery (= target artery) must be a branch of the left coronary artery. c) Preserved left ventricular function. d) Physiologic uric acid levels. The term "pharmaceutically acceptable carrier, excipient, vehicle, or diluent" refers to a medium which does not interfere with the effectiveness or activity of an active ingredient and which is not toxic to the hosts to which it is administered. A carrier, excipient, vehicle, or diluent includes binders, adhesives, lubricants, disintegrates, bulking agents, and miscellaneous materials such as absorbants that may be needed in order to prepare a particular composition. The use of such media and agents for an active substance is well known in the art. The terms "preventing and/or treating" "treatment and/or prevention", and "prophylactic and/or therapeutic" refer to administration to a subject of biologically active agents either before or after onset of a condition or disease. If the agent is administered prior to exposure to a factor causing a condition or disease the treatment is preventive or prophylactic (i.e. protects the host against damage). If the agent is administered after exposure to the factor causing a condition or disease the treatment is therapeutic (i.e. alleviates the existing damage). A treatment may be either performed in an acute or chronic way. "Functional derivative" refers to a compound that possesses a biological activity (either functional or structural) that is substantially similar to the biological activity of a compound utilized in the invention (e.g. xanthine oxidase inhibitor, ACE inhibitor, Angiotensin Receptor Blocker, or HMG CoA reductase). The term "functional derivative" is intended to include "variants" "analogs" or "chemical derivatives" of a compound. The term "variant" is meant to refer to a molecule substantially similar in structure and function to a compound or part thereof. A molecule is "substantially similar" to a compound if both molecules have substantially similar structures or if both molecules possess similar biological activity. The term "analog" refers to a molecule substantially similar in function to a compound. The term "chemical derivative" describes a molecule that contains additional chemical moieties which are not normally a part of the base molecule. A derivative may be a "physiological functional derivative" which includes but is not limited to a bioprecursor or "prodrug" which may be converted to a compound. "Xanthine oxidase inhibitor" refers to compounds that inhibit xanthine oxidase. Methods known in the art can be used to determine the ability of a compound to inhibit xanthine oxidase. (See for example the assay described in US 6,191,136). A number of classes of compounds have been shown to be capable of inhibiting xanthine oxidase, and medicinal chemists are well aware of those compounds and manners in which they may be used for such purpose. Xanthine oxidase inhibitors useful in the present invention also include their isomers, tautomers, analogs, functional derivatives, salts, solvates and prodrugs. A xanthine oxidase inhibitor for use in the present invention may be selected based on one or more of the following: (a) The compound inhibits xanthine oxidase-derived reactive species in the coronary and/or peripheral vasculature, in particular the coronary vasculature, more particularly the coronary microcirculation. (b) The compound decreases plasma xanthine oxidase activity, in particular it decreases xanthine oxidase activity by about 1-99%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%. The decrease in plasma xanthine oxidase is preferably a significant decrease. (c) The compound increases NO signalling. More particularly, the compound increases NO signalling by at least about 1% to 95%, 1% to 75%, 1% to 50%, 1% to 25% or 1% to 10%. The increase in NO signalling is preferably a significant increase. (d) The compound decreases NO catabolism when compared without the presence of the compound over the same time period. More particularly, the compound decreases NO catabolism by at least about 1% to 95%, 1% to 75%, 1% to 50%, 1% to 25% or 1% to 10%. The decrease in NO catabolism is preferably a significant decrease. (e) The compound increases hypoxanthine levels. More particularly, the compound increases hypoxanthine levels by at least about 1% to 95%, 1% to 75%, 1% to 50%, 1% to 25% or 1% to 10%. The increase in hypoxanthine is preferably a significant increase. (f) The compound substantially inhibits bound xanthine oxidase including xanthine oxidase bound to endothelial cells, in particular cardiac endothelial cells. (g) The compound attenuates vasomotor dysfunction within the coronary circulation, (h) The compound improves flow-dependent vasodilation of the brachial artery. A particular class of xanthine oxidase inhibitors that may be used in the present invention are disclosed in U.S. Patent No. 6,569,862 and PCT/US98/23878 and related references, which are incorporated by reference herein. Compounds that are particularly useful in the present invention are allopurinol (4- hydroxypyrazolo[3,4-d]pyrimidine) or oxypurinol (4,6-dihydroxypyrazolo[3,4-d]pyrimidine], or tautomeric forms thereof. Another class of xanthine oxidase inhibitors that may be used in the present invention may be exemplified by febuxostat (TEI-6720 or TMX-67; Teijin Ltd.), Xanthine oxidase inhibitors for use in the present invention can be synthesized by known procedures. Some therapeutic xanthine oxidase inhibitors also are commercially available, such as allopurinol and oxypurinol. "Combination therapy" means the administration of two or more agents to treat a disease or condition described herein. Such administration encompasses co-administration of these agents in a substantially simultaneous manner, such as in a single capsule having a fixed ratio of active ingredients or in multiple, separate capsules for each agent. In addition, such administration also encompasses use of each type of agent in a sequential manner. In either case, the treatment regimen will provide beneficial effects of the drug combination in treating the disease or condition. An "ACE inhibitor" is any agent that acts by inhibiting the conversion of angiotensin I to angiotensin II. Angiotensin converting enzyme inhibitors which may be employed herein include substituted proline derivatives, such as any of those disclosed in U.S. Pat. No. 4,046,889 or 4,105,776 to Ondetti et al, with captopril, that is, l-[(2S)-3-mercapto-2-methylpropionyl]-L-proline, carboxyalkyl dipeptide derivatives being preferred, such as any of those disclosed in U.S. Pat. No. 4,374,829, with N-(l-ethoxycarbonyl-3- phenylpropyl)-L-alanyl-L-proline, that is, enalapril, being preferred. Other examples of angiotensin converting enzyme inhibitors suitable for use in the present invention include phosphonate substituted amino or imino acids or salts disclosed in U.S. Pat. No. 4,452,790, in particular (S)-l-[6-amino-2-[[hydroxy-(4- phenylbutyl)phosphinyl]oxy]-l-oxohexyl]-L-proline (ceranapril, SQ 29,852), phosphinylalkanoyl prolines disclosed in U.S. Pat. No. 4,168,267 in particular fosinopril, mercaptoacyl derivatives of substituted prolines, disclosed in U.S. Pat. No. 4,316,906, in particular zofenopril, any of the phosphinylalkanoyl substituted prolines disclosed in U.S. Pat. No. 4,337,201, and the phosphonamidates disclosed in U.S. Pat. No. 4,432,971. Other examples of ACE inhibitors that may be employed herein include Beecham's BRL 36,378 as disclosed in European Patent Nos. 80822 and 60668; Chugai's MC-838 disclosed in CA. 102:72588v and Jap. J. Pharmacol. 40:373 (1986); Ciba-Geigy's (now Novartis) CGS 14824 (3-(l-ethoxycarbonyl-3-phenyl- (lS)-propyl]-amino)-2,3,4,5-tetrahydro-2-oxo-l-(3S)-benzazepine-l acetic acid HC1) disclosed in U.K. Patent No. 2103614 and CGS 16,617 (3(S)-[[(lS)-5-amino-l-carboxypentyl]amino]-2,3,4,5-tetrahydro-2- oxo-lH-1-benzazepine-l-ethanoic acid) disclosed in U.S. Pat. No. 4,473,575; cetapril (alacepril, Dainippon) disclosed in Eur. Therap. Res. 39:671 (1986); 40:543 (1986); ramipril (Hoechst) disclosed in Eur. Patent No. 79-022 and Curr. Ther. Res. 40:74 (1986); Ru 44570 (Hoechst) disclosed in Arzneimittelforschung 35:1254 (1985), cilazapril (Hoffman-LaRoche) disclosed in J. Cardiovasc. Pharmacol. 9:39 (1987); Ro 31-2201 (Hoffman-LaRoche) disclosed in FEBS Lett. 165:201 (1984); lisinopril (Merck) disclosed in Curr. Therap. Res. 37:342 (1985) and Eur. Patent Appl. No. 12-401, indalapril (delapril) disclosed in U.S. Pat. No. 4,385,051; rentiapril (fentiapril, Santen) disclosed in Clin. Exp. Pharmacol. Physiol. 10:131 (1983); indolapril (Schering) disclosed in J. Cardiovasc. Pharmacol. 5:643, 655 (1983); spirapril (Schering) disclosed in Acta. Pharmacol. Toxicol. 59 (Supp. 5):173 (1986); perindopril (Servier) disclosed in Eur. J. Clin. Pharmacol. 31:519 (1987); quinapril (Pfizer) disclosed in U.S. Pat. No. 4,344,949, and CI 925 (Warner- Lambert now Pfizer) ([3S-[2[R(*)R(*)]]3R(*)]-2-[2-[[l-(ethoxy-carbonyl)-3-phenylpropyl]amino[-l- oxopropyl]-l,2,3,4-tetrahydro-6,7-dimethoxy-3-isoquinolinecarboxylic acid HC1) disclosed in Pharmacologist 26:243, 266 (1984), WY-44221 (Wyeth) disclosed in J. Med. Chem. 6:394 (1983). In particular embodiments, the ACE inhibitors that can be used in the novel compositions and methods of this invention are enalapril, lisinopril, captopril alacipril, benazapril, cilazapril, delapril, fosinopril, perindopril, quinapril, ramipril, moexipril, moveltipril, spirapril, ceronapril, imidapril, temocapril, trandolopril, utilbapril, zofenopril, (R)-3-[(S)-l-carboxy-5-(4-piperidyl)pentyl]amino-4-oxo-2,3,4,5- tetrahydro-l,5-benzothiazepine-5-acetic acid, libensapril, zalicipril, n-octyl 2-[N-[(S)-l-ethoxycarbonyl-3- phenylpropyl]-L-alanyl]-(lS,3S,5S)-2-azabicyclo[3,3,0]octane -3-carboxylate maleate salt, 7-[(S)-l-carboxy- 3-phenylpropyl)amino] [4S-[4α,7 (R), 12bβ]]- 1 ,2,3,4,5,6,7,8, 12b-octahydro-6-oxopyrido[2, 1 - a] [2]benzazepine-4-carboxylic acid, N-[8-amino- 1 (S)-carboxyoctyl]-L-alanyl-L-proline, 3-pyridylcarbonyl- Lys-.alpha.-D-Glu-perhydroindole-2-carboxylic acid, benzhydryl[4α,7α.(R), 12bβ]-7-[[ 1 -

(ethoxycarbonyl)phenylpropyl]amino]- 1 ,2,3,4,6,7, 12a, 12b-octahydro-6-oxopyrido[2, 1 -a] [2]benzazepine-4- carboxylate, l-(N-((lS)-l-carboxy-3-phenylpropyl)-(S)-alanyl-4-(N-methyl-N-(6-chloro-7-sulfamoyl)-3,4- dihydro-l,2,4-benzothiadiazine-l,l-dioxide-3-yl)methyl)aminoproline. In embodiments of the invention the ACE inhibitors are enalapril, lisinopril, captopril, perindopril, benzapril, quinapril, cilazapril, ramipril, fosinopril, perindropril, perindropril tert-butylamine, rrandolapril or moexipril. The ACE inhibitors useful in the present invention also include their isomers, tautomers, analogs, functional derivatives, salts, solvates and prodrugs. "Angiotensin Receptor Blockers (ARB) are understood to be those active ingredients which bind to the ATi-receptor subtype of angiotensin II receptor but do not result in activation of the receptor. Examples of Angiotensin Receptor Blockers are candesartan, eprosartan, candesartan cilexetil, eprosartan, irbesartan, saprisartan, tasosartan, losartan, olmesartan, telmisartan, valsartan, and prodrugs and salts thereof. As used herein the term "HMG CoA reductase inhibitor" or the term "statin" means any entity derived from chemical or biological sources which inhibits HMG CoA reductase activity. Any type of HMG- CoA reductase inhibitors can be used according to the present invention. Examples of HMG CoA reductase inhibitors that may be utilized in the present invention include lovastatin, pravastatin, simvastatin, fluvastatin, mevastatin, atorvastatin and derivatives and analogs thereof. The majority of these inhibitors are produced by fermentation using microorganisms of different species identified as species belonging to Aspergillus, Monascus, Nocardia, Amycolata species, Mucor or Penicillium genus, some are obtained by treating the fermentation products using the methods of chemical synthesis, leading to semi-synthetic substances, or they are the products of complete chemical synthesis. The HMG CoA reductase inhibitor compounds useful in the present invention also include their isomers, tautomers, analogs, functional derivatives, salts, solvates and prodrugs. A "glycosaminoglycan" refers to linear chains of largely repeating disaccharide units of hexosamine and a urohic acid. A disaccharide may optionally be modified by alkylation, acylation, sulfonation (O- or N- sulfated), sulfonylation, phosphorylation, phosphonylation and the like. The length of a chain may vary and the glycosaminoglycan may have a molecular weight between 50,000 to 200,000 daltons Representative examples of glycosaminoglycans include, heparin, dermatan sulfate, heparan sulfate, chondroitin-6-sulfate, chondroitin-4-sulfate, keratan sulfate, chondroitin, hyaluronic acid, polymers containing N-acetyl monosaccharides (such as N-acetyl neuraminic acid, N-acetyl glucosamine, N-acetyl galactosamine, and N- acetyl muramic acid) and the like and gums such as gum arabic, gum Tragacanth and the like. See Heinegard, D. and Sommarin Y. (1987) Methods in Enzymology 144:319-373. A vascular and/or cardiovascular disease or dysfunction contemplated herein includes but is not limited to, a disorder associated with one or more of impaired coronary endothelial function, impaired myocardial perfusion, impaired NO-dependent signalling, impaired NO catabolism, impaired vascular NO bioavailabihty, and a disorder requiring suppression of reactive species including superoxide, hydrogen peroxide, and/or superoxide peroxynitrite. A vascular and or cardiovascular disease or dysfunction include but are not limited to a disorder in coronary blood flow and/or cardiac function following coronary catheterization, angioplasty, endarterectomy, by-pass grafting or any other coronary artery surgery or manipulation. In particular embodiments of the invention the condition or disease is coronary artery dysfunction, coronary endothelial dysfunction, coronary heart disease or coronary artery disease. "Coronary heart disease (CHD)" also known as "ischemic heart disease (IHD)" refers to any of a group of acute or chronic cardiac disabilities resulting from insufficient supply of oxygenated blood to the heart; it may be due to increased oxygen demand, to diminished blood oxygen transport, or most commonly to reduction in coronary blood flow because of arterial narrowing or obstruction such as that caused by atherosclerosis. It may manifest as angina pectoris, myocardial infarction, ventricular fibrillation, or sudden cardiac death. "Coronary artery disease (CAD)" refers to atherosclerosis of the coronary arteries, which may cause a variety of symptomatic conditions including but not limited to angina, myocardial infarction, sudden cardiac death and non-specific chest, arm and face pain. These conditions generally result from atherosclerosis of the arteries that supply blood to the heart. Atherosclerosis or "hardening of the arteries" is caused by the formation of deposits of fatty substances such as cholesterol within the inner layers or endothelium of the arteries. Both genetically determined and avoidable risk factors contribute to the disease; they include hypercholesterolemia, hypertension, smoking, diabetes mellitus, and low levels of high density lipoproteins. In embodiment of the invention coronary artery disease includes myocardial infarction, vascular hypertrophy, and vascular damage following diabetic and non-diabetic renal disease, and vascular damage associated with angioplasty and atheroma. A cardiovascular disease contemplated herein also includes, for example, hypertension, hypertrophy, congestive heart failure, stroke, heart failure subsequent to myocardial infarction, arrhythmia, myocardial ischemia, myocardial infarction, ischemia reperfusion injury, and diseases that arise from thrombotic and prothrombotic states in which the coagulation cascade is activated. A vascular disease also includes inflammatory vascular diseases or vasculitis. Inflammatory vascular diseases or vasculitis refers to diseases involving inflammation of blood vessels including arteritis, giant cell arteritis, Takayasu's arteritis, atherosclerosis, and transplant stenosis. The methods, compositions, and uses of the invention provide beneficial effects. Beneficial effects include but are not limited to, providing improved prognosis and protection against vascular and/or cardiovascular disease, in particular, protection against vascular and/or cardiovascular disease as evidenced by improved clinical outcomes following coronary catheterization, angioplasty, endarterectomy, by-pass grafting or any other coronary artery surgery or manipulation; providing protection against vascular and/or cardiovascular disease as evidenced by maintained lumenal patency or vessel diameter following coronary catheterization, angioplasty, endarterectomy, by-pass grafting, stent placement or any other coronary artery surgery or manipulation; providing protection against coronary artery disease as evidenced by prolonged time to blood vessel spasm or closure following coronary catheterization, angioplasty, endarterectomy, bypass grafting, stent placement or any other coronary artery surgery or manipulation as evidenced by reduction in the need for medication to improve cardiac blood flow or diminish pain associated with angina; providing protection against coronary artery disease as evidenced by prolonged time to blood vessel spasm or closure following coronary catheterization, angioplasty, endarterectomy, by-pass grafting, stent placement or any other coronary artery surgery or manipulation as evidenced by reduction in the need for medication to improve cardiac function in patients with heart disease; providing protection against coronary artery disease as evidenced by prolonged time to re-hospitalization for heart disease following coronary catheterization, angioplasty, endarterectomy, by-pass grafting, stent placement or any other coronary artery surgery or manipulation; providing protection against coronary artery disease as evidenced by prolonged time to worsening of heart disease following coronary catheterization, angioplasty, endarterectomy, by-pass grafting, stent placement or any other coronary artery surgery or manipulation; providing protection against coronary artery disease as evidenced by decreased need for medications in patients with heart disease following coronary catheterization, angioplasty, endarterectomy, by-pass grafting, stent placement or any other coronary artery surgery or manipulation. Coronary insufficiency is another example of coronary artery disease. Comvositions and Methods The invention provides a pharmaceutical composition for the treatment of coronary heart disease comprising an effective amount of a xanthine oxidase inhibitor and a pharmaceutically acceptable carrier, excipient, vehicle, or diluent. In an embodiment of the invention, a pharmaceutical composition comprising a xanthine oxidase inhibitor is desirable to markedly improve artery dysfunction, in particular cardiac blood flow, more particularly coronary artery blood flow, increase coronary artery diameter, or restore the ability of coronary arteries to increase in diameter in subjects with coronary heart disease. In another embodiment, a pharmaceutical composition is provided which has been adapted for administration to a subject to produce, or is in a form that produces, one or more of the following: reduced or suppressed xanthine oxidase-derived reactive species, improved NO bioavailabihty, increased NO- dependent signalling in the coronary vasculature, decreased NO catabolism in the coronary vasculature, improved endothelial function, restored ability of the coronary artery to increase in diameter, improved coronary artery blood flow, improved endothelium-dependent vasodilation, attenuated vasomotor dysfunction, normalized vascular function, and/or, normalized levels of enzymes and other biomarkers of coronary artery disease. In particular embodiments, the xanthane oxidase inhibitor is allopurinol or oxypurinol, more particularly oxypurinol, which is directed to preventing and/or treating coronary artery disease. The compositions of the present invention typically comprise suitable pharmaceutical carriers, excipients, vehicles, or diluents selected based on the intended form of administration, and consistent with conventional pharmaceutical practices. Pharmaceutical compositions according to the present invention include those suitable for oral, rectal, transdermal, pulmonary, topical, buccal (e.g., sublingual), and parenteral (e.g., subcutaneous, intramuscular, intradermal, or intravenous) administration, although the most suitable route in any given case will depend on the nature and severity of the condition being treated and on the nature of the particular compound which is being used. Suitable pharmaceutical carriers, excipients, vehicles, or diluents are described in the standard text, Remington's Pharmaceutical Sciences (Mack Publishing Company, Easton, Pa., USA 1985). By way of example, for oral administration in the form of a capsule or tablet, the active components can be combined with an oral, non-toxic pharmaceutically acceptable inert carrier such as lactose, starch, sucrose, methyl cellulose, magnesium stearate, glucose, calcium sulfate, dicalcium phosphate, mannitol, sorbitol, and the like. For oral administration in a liquid form, the drug components may be combined with any oral, non- toxic, pharmaceutically acceptable inert carrier such as ethanol, glycerol, water, and the like. Suitable binders (e.g. gelatin, starch, corn sweeteners, natural sugars including glucose; natural and synthetic gums, and waxes), lubricants (e.g. sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, and sodium chloride), disintegrating agents (e.g. starch, methyl cellulose, agar, bentonite, and xanthan gum), flavoring agents, and coloring agents may also be combined in the compositions or components thereof. Compositions of the invention can also include absorption enhancers, particle coatings (e.g. enteric coatings), lubricants, targeting agents, and any other agents known to one skilled in the art. A composition may contain from about 0.1 to 90% by weight (such as about 0.1 to 20% or about 0.5 to 10%) of the active ingredient. The percentage of active ingredient in each pharmaceutical composition and the therapeutically effective amount of the active ingredient used to practice the present invention for treatment of the disclosed conditions depend upon the manner of administration, the age and the body weight of the subject and the condition of the subject to be treated, and ultimately will be decided by the attending physician or veterinarian. Dosaging may also be arranged in a subject specific manner to provide a predetermined concentration of a xanthine oxidase inhibition activity in the blood. For example, dosaging may be adjusted to achieve regular ongoing trough blood levels of a xanthine oxidase inhibitor on the order of from 50 to 1000 ng ml, in particular, 55 to 150 ng/ml. The compositions described herein may be used to prevent or treat conditions or diseases described herein. Therefore, the invention relates to a method for preventing and/or treating in a subject a condition or disease described herein comprising administering an effective amount of a composition of the invention. In an embodiment, the condition or disease is coronary artery disease or coronary heart disease. In another embodiment, the composition comprises oxypurinol. A pharmaceutical composition described herein may provide advantageous effects in the treatment of conditions or diseases such as vascular and/or cardiovascular diseases or dysfunctions, or related diseases. The compositions can be readily adapted to therapeutic use in the treatment of coronary artery disease or coronary heart disease. Thus, the invention contemplates the use of a composition described herein for preventing, and/or ameliorating disease severity, disease symptoms, and/or periodicity of recurrence of a vascular and/or cardiovascular disease, in particular coronary artery disease or coronary heart disease. In another aspect the invention relates to the use of a xanthine oxidase inhibitor or composition described herein in the preparation of a medicament, in particular a medicament for the prevention or treatment of a condition or disease described herein. In an embodiment the condition or disease is a vascular and/or cardiovascular or related disease, in particular coronary artery disease. In another aspect the invention relates to the use of effective amounts of a composition described herein, in the preparation of a pharmaceutical composition for inhibiting or preventing a condition or disease, in particular a vascular and/or cardiovascular or related disease, in a patient. In an embodiment, the condition or disease is coronary heart disease or coronary artery disease. The methods and uses of the invention include both acute and chronic therapies. For example, a composition of the invention can be administered to a patient suffering from a vascular and/or cardiovascular disease, in particular coronary artery disease or coronary heart disease. Regular long-term administration of a composition described herein may be beneficial after a patient has suffered from chronic heart failure to provide increased exercise tolerance and functional capacity. Therefore, a composition described herein can be administered on a regular basis to promote enhanced functional capacity, for example, at least, 2, 4, 6, 8, 12, 16, 18, 20, or 24 weeks, or longer such as 6 months, 1 year, 2 years, 3 years, or more after having suffered heart failure. In an embodiment, the invention relates to a method for treating coronary artery disease or coronary heart disease in a subject comprising administering a pharmaceutical composition of the invention to the subject, and continuing administration of the formulation until a desirable therapeutic effect is detected in the subject. The desired therapeutic effect may be one or more of the following: improved NO bioavailabihty, increased NO-dependent signalling in the coronary vasculature, decreased NO catabolism in the coronary vasculature, reduced or suppressed xanthine oxidase-derived reactive species, improved endothelial function, restored ability of the coronary artery to increase in diameter, improved coronary artery blood flow, improved endothelium-dependent vasodilation, attenuated vasomotor dysfunction, normalized vascular function, and/or normalized levels of enzymes and other biomarkers of coronary artery disease. Routes of administration of a composition of the invention include oral,rectal, pulmonary, nasal, topical, buccal (sublingual), transdermal, and parenteral (e.g. intravenous, intramuscular, intradermal,and subcutaneous routes), and the like. In the therapeutic methods of the invention, a single or combination of xanthine oxidase inhibitors may be administered. Thus, a particular therapy can be optimized by selection of an optimal therapeutic xanthine oxidase inhibitor, in particular allopurinol or oxypurinol, or an optimal cocktail of multiple xanthine oxidase inhibitors. Optimal compound(s) can be readily selected by those skilled in the art using known in vitro and in vivo assays, examples of which are described herein. The amounts of active substances in the compositions used in therapeutic methods of the invention will vary according to various factors including but not limited to the specific compounds being utilized, the particular compositions formulated, the mode of application, and the site of administration. Conventional dosage determination tests can be used to ascertain the optimal administration rates for a given protocol of administration. Doses utilized in prior clinical applications for xanthine oxidase inhibitors will provide guidelines for preferred dosage amounts for the methods of the present invention. Compositions and methods of the invention comprise a concentration or dose of a xanthine oxidase inhibitor that provides one or more desired therapeutic effect described herein. In particular, a composition or method can utilize a concentration or dose of xanthine oxidase inhibitor that results in a decrease in plasma xanthine oxidase activity in a subject of at least about 1-99%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%,50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99%. The concentration or dose of a xanthine oxidase inhibitor can be selected that substantially inhibits one or both of free xanthine oxidase and bound xanthine oxidase, including xanthine oxidase bound to endothelial cells. Combination Therapy The invention also relates to a combination therapy for preventing and/or treating a vascular and/or cardiovascular disease, in particular coronary artery disease, coronary artery dysfunction, or coronary endothelial dysfunction comprising administering to a patient two or more of a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more agent that improves NO bioavailabihty. In an aspect, the glycosaminoglycan is heparin. In another aspect, an agent that improves NO bioavailabihty is an ACE inhibitor or a HMG CoA reductase inhibitor. A combination therapy of the invention may comprise an Angiotensin Receptor Blocker. , The invention contemplates a pharmaceutical composition or combination comprising one or more xanthine oxidase inhibitor, a glycosaminoglycan, and/or one or more agent that improves NO bioavailabihty. An agent that improves NO bioavailabihty includes an ACE inhibitor and a HMG CoA reductase inhibitor. A combination therapy of the invention may also comprise an Angiotensin Receptor Blocker. Thus, a composition or combination may comprise a xanthine oxidase inhibitor, a glycosaminoglycan, an ACE inhibitor, Angiotensin Receptor Blocker, and/or a HMG CoA reductase inhibitor. In an embodiment, the pharmaceutical composition or combination comprises a xanthine oxidase inhibitor and an ACE inhibitor. In another embodiment, the pharmaceutical composition or combination comprises a xanthine oxidase inhibitor and a HMG CoA reductase inhibitor. In a further embodiment, the pharmaceutical composition or combination comprises a xanthine oxidase inhibitor and a glycosaminoglycan, and optionally an agent that improves bioavailabihty. In particular, a composition or combination can comprise a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more of an ACE inhibitor, Angiotensin Receptor Blocker, and an HMG CoA reductase inhibitor. Particular aspects of the invention contemplate a combination therapy or pharmaceutical composition wherein each agent is present in a concentration effective to provide an additive effect. Other particular aspects of the invention contemplate a combination therapy or pharmaceutical composition wherein each agent is present in a concentration to provide a synergistic effect. The combinations of the present invention can have a number of uses. For example, through dosage adjustment and medical monitoring, the individual dosages of the agents used in the combinations of the present invention will be lower than are typical for dosages of the agents when used in monotherapy. The dosage lowering will provide advantages^' including reduction of any side effects of the individual agents (in particular side effects associated with an ACE inhibitor, Angiotensin Receptor Blocker, or HMG CoA reductase) when compared to the monotherapy. In addition, fewer side effects of the combination therapy compared with the monotherapies will lead to greater patient compliance with therapy regimens. Another use of the present invention will be in combinations having complementary effects or complementary modes of action. For example, HMG CoA reductase inhibitors control blood serum cholesterol levels by inhibiting an enzyme which is important in the biosynthesis of cholesterol. In contrast, xanthine oxidase inhibitors inhibit xanthane oxidase which may thereby reduce xanthine-derived reactive species in the coronary vasculature. The xanthine oxidase inhibitor, glycosaminoglycan, and agent can be administered by any conventional means available for use in conjunction with pharmaceuticals, either as individual therapeutic compounds or as a combination of therapeutic compounds. The amount of each compound which is required to achieve the desired biological effect will, of course, depend on a number of factors such as the specific compound chosen, the use for which it is intended, the mode of administration, and the clinical condition of the recipient. A total daily dose of an HMG CoA reductase inhibitor can generally be in the range of from about 0.01 to about 100 mg/kg body weight/day in single or divided doses. For example, lovastatin, atorvastatin, or mevastatin, generally are each administered separately in a daily dose of about 10 to about 80 mg/day. For an ACE inhibitor, a total daily dose of about 0.01 to about 100 mg/kg body weight/day may generally be appropriate, and for a glycosaminoglycan, a total daily dose of about 0.01 to about 100 mg/kg body weight /day may generally be appropriate. A daily dose for the various therapeutic compounds can be administered to the patient in a single dose, or in proportionate multiple subdoses. Subdoses can be administered 2 to 6 times per day. Doses can be in sustained release form effective to obtain desired results. The combinations of the present invention can be delivered orally either in a solid, in a semi-solid, or in a liquid form. When in a liquid or in a semi-solid form, the combinations of the present invention can, for example, be in the form of a liquid, syrup, or contained in a gel capsule (e.g. a gel cap). For example, when an HMG CoA reductase inhibitor is used in a combination of the present invention, the HMG CoA reductase inhibitor can be provided in the form of a liquid, syrup, or contained in a gel capsule. In a composition or combination therapy of the invention, the xanthine oxidase inhibitor, glycosaminoglycan, and agent (e.g. ACE inhibitor, Angiotensin Receptor Blocker, and/or HMG CoA reductase inhibitor) can be present in a single dosage form, for example a pill, a capsule, or a liquid which contains the compounds. Having now described the invention, the same will be more readily understood through reference to the following examples which are provided by way of illustration, and are not intended to be limiting of the present invention. EXAMPLES Example 1 Effect of Oxypurinol on NO-Dependent Relaxation of Coronary Blood Flow The primary goal of the study was to evaluate the effect of oxypurinol on the NO-dependent relaxation of the coronary blood flow. To do so, in patients with coronary heart disease, the acetylcholine- dependent relaxation in an epicardial coronary vessel was measured by quantitative coronary angiography before and immediately after an infusion of oxypurinol. Serum specimens taken from a peripheral vein were tested for xanthine oxidase activity, myeloperoxidase level and activity. The serum specimens were also used for analysis of the XO-dependent formation of peroxynitrite by analysis of the nitrotyrosine levels before and after inhibition of xanthine oxidase. ι

Test Substance The test medication used consists of oxypurinol. Oxypurinol was prepared by the pharmacy of the Hamburg Eppendorf University Hospital for i.v. administration. The test substance, oxypurinol (200 mg) was packaged in containers and was dissolved in 5% dextrose for infusion. The study medications were stored at all times in closed containers at room temperature and they were not to be stored at temperatures above 25°C. Study design and Plan The clinical study described was a prospective monocenter study. The patients selected for the study had coronary heart disease, including generalized changes in the wall of the coronary arteries or a significant stenosis in one or two branches of the coronary arteries for which PCT A, stent implantation or another percutaneous procedure are planned. After intervention, the endothelium-dependent relaxation and the reserve flow in the coronary arteries was determined on these patients under acetylcholine in increasing doses (10^~7, 10^"6, 10^"5 mol/L). The target artery was an artery of the left coronary arteries which is not occluded according to angiography and has minimal lesions (stenosis <40%). Before the measurement, serum specimens were taken from a peripheral vein. Then oxypurinol was administered by infusion, and relaxation of the artery as well as the coronary reserve flow under acetylcholine was determined again, and finally a serum specimen was taken again from a peripheral vein. Selection of patients Primary diagnosis Patients with coronary heart disease were included in the study. In a diagnostic coronary angiogram, which should not be more than two weeks in the past at the time of the first visit, the patient must show coronary findings necessitating PTCA, stent implantation or some other percutaneous procedure for at least one blood vessel. As an alternative, patients are included in whom coronary heart disease including generalized wall changes has been detected in a diagnostic coronary angiogram. Patients were informed regarding the significance and extent of the study before performing the coronary angiogram. The acetylcholine test and the infusion of oxypurinol were performed according to the study protocol within the same catheter examination. Patients who met all the inclusion criteria without any of the exclusion criteria were included in the study on a randomized basis if they had a clinical indication for coronary revascularization after successfully performing PTCA, stent implantation or some other percutaneous procedure or if they showed generalized changes in the walls of the coronary arteries after all the coronary arteries have been visualized by angiography. The inclusion criteria were as follows: Angiographically documented coronary heart disease with a) generalized wall changes (stenosis <40%) and/or b) existence of a significant lesion with the indication for percutaneous primary intervention in one or two coronary artery branches. Existence of a coronary artery that is not occluded according to angiography and has only minimal lesions (stenosis <40%); this artery (= target artery) must be a branch of the left coronary artery. Patients must be more than 18 years of age. Written consent by the patient to participate in the study. The exclusion criteria were as follows: With respect to the patient's medical history: Myocardial infarction within two weeks before the study (Exception: patients with a non-Q-wave infarction may be included, depending on the judgment of the investigator). Unstable angina pectoris, unless the lesions on which the condition is based are stabilized by the current procedure Aortocoronary bypass surgery within four weeks the start of the study Stroke or peripheral revascularization within twelve weeks before the study Hyperuricemia (uric acid >7.3 mg/dL) A known intolerance to oxypurinol and/or allopurinol Chronic liver disease Clinically significant heart valve disease Hypertrophic obstructive cardiomyopathy Persistent ventricular arrhythmias Syncope within four weeks prior to the study Severe respiratory tract disease Known hypothyroidism Known hyperthyroidism Allergy to the contrast medium The presence of another disease (excluding coronary heart disease) which could limit life expectancy A history of organ transplantation With respect to medications being taken currently: Allopurinol preparations taken in the last two weeks before inclusion in the study Intravenous heparinization within the last 24 hours before inclusion With respect to the current symptoms or findings: Clinically significant cardiac insufficiency based on the presence of a left ventricular ejection fraction of <40% (measured with LV angiography or echocardiography). Symptoms of orthostatic hypotension or a systolic blood pressure of <80 mm Hg lying down. Systolic blood pressure >200 mm Hg and/or diastolic blood pressure >115 mm Hg despite antihypertensive therapy. Renal damage with serum creatinine levels of >1.2 mg/dL or a known nephrotic syndrome. ALAT (alanine aminotransferase) or ASAT (aspartate aminotransferase) >1.5 times higher than the upper normal level. Miscellaneous: In women: pregnancy, nursing or risk of pregnancy (women of childbearing age may be included if they are using an acceptable method of birth control). Simultaneous participation in another study. Treatment with a product that is in the testing phase within a period of 30 days prior to the study. Treatment The patients were treated as follows: Oxypurinol (13.4 mg/min) was administered by infusion at a rate of 1 mL/min for 15 minutes through a peripheral vein. The dose was 200 mg per patient. According to the "Physician's Desk Reference," the intravenous dose of allopurinol which should be administered is 600 mg. According to the Professional Information Brochure, which was translated from the Dutch and is in use in Germany, the dose of allopurinol is 1000 mg. A dose of 1000 mg allopurinol administered intravenously is metabolized by direct oxidation to 1118 mg oxypurinol. Allopurinol is converted to oxypurinol with a half-life of one hour, and the half-life of oxypurinol is 24 hours. A 1000 mg infusion of allopurinol leads to a plasma allopurinol concentration of approximatley 17 μg/mL at the end of the infusion time of 30 minutes, with a maximum oxypurinol level of 21 μg/mL four hours later. Accordingly, a 15-minute infusion of oxypurinol leads to a plasma concentration of 4 to 5 μg/mL at the end of the infusion. The treatment began as part of the coronary angiography after performing the intracoronary acetylcholine tests. The duration of the one-time treatment was 15 minutes. The patients were checked for suitability for inclusion in the study in a period of up to 14 days before the planned intervention. This applied in particular to the diagnostic coronary angiography. However, the screening could also have been conducted on the same day. Each patient was monitored closely during the treatment phase in the heart catheter laboratory and in the last 24 hours after the oxypurinol infusion. All patients who had taken a study medication at any time were observed in follow-up for a period of at least 30 days. The follow-up was implemented by having the patient return to the outpatient clinic or by interviewing the patient by telephone. Patients experiencing adverse events and/or adverse effects of the medication were tracked during follow-up in shorter intervals according to the decision of the study director. Measurements: Evaluation of the effects of treatment Intracoronary acetylcholine test Prerequisites All patients will have an angiographically confirmed coronary heart disease with either a stenosis in one or two coronary artery branches sufficient to require intervention or the picture of a generalized coronary arteriosclerosis with stenosis <40% in all three coronary artery branches. The left ventricular ejection fraction measured by angiography or echocardiography should be >40%. Definition of the target artery The target artery is the coronary artery in which the acetylcholine test is to be performed. The target artery must not have any stenoses >40% and must be a branch of the left coronary artery. If there are several suitable branches of the left coronary artery, the branch having the largest diameter will be selected as the target artery. Procedures Quantitative coronary angiography and intracoronary Flowirc measurement In the case of a stenosis requiring intervention, this was treated before the acetylcholine test, oxypurinol infusion and subsequent acetylcholine test. For the measurements, the patient received anticoagulant therapy in the form of 7500 IU heparin i.v. A 6F or 7F guide catheter was introduced into the main trunk of the left coronary artery. The target artery was characterized in that it did not have any stenoses amounting to more than 40% of the vascular diameter and it was not intended for angioplasty. The coronary flow measurements were performed by using a Doppler guide wire (Flowire®, Cardiometrics). The wire was advanced carefully into the coronary artery not having a high-grade stenosis and was positioned so as to derive an optimum Doppler signal. If the basal flow rate was less than 8 cm per second or the quality of the signal was inadequate, that patient was excluded from the measurement and only quantitative coronary angiography was performed. Then a Tracker catheter was introduced over the guide wire into the proximal section of the target artery. The X-ray system was brought into the position permitting the best visualization of the target artery. The vertical and horizontal adjustment of the X-ray system were noted in writing in the case report form. Then the contrast medium was injected into the target artery and an angiogram was prepared. Acetylcholine in increasing doses (10^"7, 10^"6, 10^'5 mol L) was then infused for three minutes each through the Tracker catheter. At the end of each dose, an angiogram was prepared while the contrast medium was being injected, and the coronary flow was determined continuously by Flowire Doppler sonography. After a waiting time of five minutes, a new angiogram was prepared as the baseline measurement. Oxypurinol was administered by intravenous infusion over the following fifteen minutes. Then acetylcholine and nitroglycerin were injected as described above. Sixty seconds after administration of 200 μg nitroglycerin into the target artery, a concluding angiogram was prepared. The coronary flow measurements were recorded after each intracoronary infusion of Ach and after administration of nitroglycerin. The coronary flow reserve was calculated by calculating the quotient of the maximum flow rate to the initial flow rate. Blood (a total 20 mL) was taken from a peripheral vein before and after the oxypurinol infusion. Analysis The angiograms were stored in DICOM format on a CD. The artery diameters were analyzed by an automatic contour finding program. The target artery was divided into 5 mm segments, beginning proximally, up to a maximum of ten segments (=5 cm). The diameters of all segments were measured in the individual angiograms. The segment having the least vasodilation in response to Ach or having the greatest vasoconstriction in response to acetylcholine (SMAV = site of maximal abnormal vasoactivity) was included in the analysis and compared with the vascular diameter of this segment after treatment with oxypurinol. The primary measured quantity is the change in the SMAV diameter in response to the maximum tolerated acetylcholine concentration in %. Intracoronary flow was determined digitally during the entire measurement and correlated after the intervention with the various doses of Ach. The flow profiles before and after administration of oxypurinol were then compared. Biochemical markers Plasma oxypurinol concentration Before and after infusion of the test substance, blood (20 mL each time) was taken from a peripheral vein and the serum was stored at -80°C. It was then tested for oxypurinol by means of high- resolution liquid chromatography (Department of Professor Freeman of the University of Alabama at Birmingham). Xanthine oxidase activity before and after treatment with oxypurinol The patients' serum before and after injection of the test substance was tested for xanthine oxidase activity by means of high-resolution liquid chromatography (Prof. Freeman, University of Alabama at Birmingham). Myeloperoxidase level and activity Myeloperoxidase levels was determined by ELISA, and an NO electrode was used to determine the catalytic activity of NO oxidation by myeloperoxidase. 3-Niirotyrosine levels in the serum before and after treatment with oxypurinol For quantitative determination of serum 3-nitrotyrosine levels, serum specimens was analyzed by gas chromatography and mass spectrometry at the Department of Professor Freeman of the University of Alabama at Birmingham, USA. Clinical chemical laboratory determinations The following laboratory parameters were determined: Creatinine, urea, and potassium were determined before the intervention procedure and at the time of discharge of the patient. C-reactive protein, glucose, uric acid, folic acid, total cholesterol, HDL cholesterol and triglycerides were determined at visits 1 and 5. LDL cholesterol was calculated by using the Friedewald formula LDL concentration = Total cholesterol -[(HDL+ triglycerides)/5] Before the intervention procedure and before the patients were discharged, a 12-channel ECG was recorded. Clinical examination A clinical examination was performed at each visit along with recording information for the patient files and determining the body mass index. Concomitant medications All vasoactive medications were stopped at least twelve hours before beginning the study. Vasoactive medications included long-acting nitrates, molsidomine, calcium antagonists, β-blockers, trapidil and dipyridamole. Short-acting nitrates were not to be taken within the last three hours before the intervention period. The patient should not have received any intravenous heparin in the last 24 hours before the intervention. Exclusion of patients from the study Each patient who is excluded from the study for any reason was listed as a drop-out. The following grounds required premature exclusion from the study: Withdrawal of consent for participation in the study. Occurrence of serious adverse effects which are attributed to the study medication with a high probability. Likewise, an allergic reaction to the test substance: rash, pruritus, tachycardia. Symptomatic hypertension under the lowest dose used for treatment. Systolic blood pressure <90 mm Hg in repeated measurements under the lowest dose used for treatment. Criteria for evaluating the success of the study and the safety of the study Intention-to-treat analysis All patients in whom a valid examination was performed were included in the analysis of the efficacy parameters even in cases which violate the study protocol. Safety analysis All patients receiving the test substance in an infusion for at least ten minutes were included in the safety analysis. All unusual events and adverse effects were recorded in the patient documentation sheet together with the time, duration, severity, therapeutic consequence and course of the events or effects. Study goals Primary efficacy parameters A primary efficacy parameter that was investigated was acetylcholine-induced change in the diameter of the coronary artery. As part of the angiography, the change in the average diameter of the target artery was measured in net percent after incrementally increasing the intracoronary acetylcholine infusion with concentrations of 10^" ⁷, 10^'6, 10^"5 mol L (with an infusion rate of 2 mL/min for three minutes each) before and after infusion of oxypurinol. Furthermore, the intracoronary flow rate before and after the oxypurinol infusion was also determined as part of the acetylcholine infusion. The first primary end point is the net difference in the diameter of the coronary artery segment showing the greatest constriction in response to acetylcholine in a dose of 10^"5 mol L before and after infusion of oxypurinol in percentage points. If 10^'5 mol/L acetylcholine is not tolerated, the values obtained at the highest dose of acetylcholine tolerated in both measurements were compared. Secondary efficacy parameters The following secondary efficacy parameters were analyzed: Change in activity of xanthine oxidase in the serum before and after the oxypurinol treatment. Determination of the oxypurinol levels before and after administration of oxypurinol. Determination of myeloperoxidase levels and activity in the serum. Changes in the serum nitrotyrosine levels (measured before and after infusion of the study substance). Pharmacokinetics Measurement of the plasma concentrations of the study medication were conducted. Statistical Analysis The statistical evaluation of the study was done after the conclusion of all the examinations using the statistical analysis package SPSS® in cooperation with the Institute for Mathematics and Data Processing in Medicine of the Hamburg-Eppendorf University Hospital (Prof. Dr. J. Berger, Director). The primary endpoint of this study is the change (measured in percent) of the coronary vessel reaction induced by acetylcholine before and after infusion of oxypurinol. The null hypothesis H₀ with respect to this endpoint is:

Ho : On the average, pretreatment with oxypurinol in patients with coronary heart disease does not result in any percentage change in diameter of the coronary artery segments which constrict most strongly in response to 10^"6 M acetylcholine. The alternative hypothesis Hi with respect to his endpoint is: Hi : On the average, pretreatment with oxypurinol in patients with coronary heart disease results in a percentage change in diameter of the coronary artery segments which constrict most strongly in response to 10^"6 M acetylcholine. If a standard deviation of 25% is assumed for recognition of a difference of 7% between the two treatment groups with the two-group t-test at a power of 80% and an α error of 0.5%, then the sample size required to detect a difference for

is 20 patients per treatment group. The estimates of the standard deviation and of the clinically relevant difference are based on studies published in the literature, with comparable design and comparable questions. The primary analysis is done according to the intention-to-treat principle. A total of 20 patients is required. The following secondary endpoints were given a purely exploratory statistical evaluation: 1. Measurement of the oxypurinol concentration in serum obtained from a peripheral vein before and after administration of oxypurinol. 2. The change in the xanthine oxidase activity in the serum before and after treatment with oxypurinol. 3. Determination of the myeloperoxidase concentration and activity in the serum before and after oxypurinol infusion. 4. The nitrotyrosine concentration in the serum obtained from a peripheral vein before and after treatment with oxypurinol. The results of the statistical evaluation of the secondary endpoints are not to be interpreted as confirmatory. They are intended only to assist formulation of hypotheses for more extensive prospective studies. All the variables mentioned were summarized using random sample statistics (means, standard deviations, medians, quartiles and maximum values) for quantitative date, or using frequency tables for qualitative data/data categories. These computations were done generally and by treatment groups. Comparison of treatment groups The comparability of the treatment groups was tested for the patient population selected according to ITT as well as for the patient population selected with respect to efficacy, taking demographic criteria and the target criterion at the beginning of the test into consideration. Continuous variables were analyzed with F tests derived from ANOVA models, and categoric variables were analyzed with Cochran-Mantel-Haenszel tests. Analysis of efficacy The primary endpoint was the change in the reaction of coronary vessels to 10^"5 M acetylcholine. If acetylcholine cannot be administered because of excessive vasoconstriction, the reaction was compared at the maximum tolerated acetylcholine concentration in the initial measurement and after infusion of oxypurinol (e. g., 10^"6 M with 10^"6 M, or 10^"7 M with 10^"7 M. Two-tailed t-tests (each of which compares two treatments) were derived so as to be able to compare the two different treatment groups with each other. Analysis of safety The safety analysis included a tabular presentation of the nature and frequency of all side-effects. Changes in the laboratory tests were shown both by treatment group and also according to values lying outside the normal range. The treatment groups were compared with respect to the incidence of adverse events. A tabular presentation of the nature and frequency of adverse events was established according to the COSTART glossary. Table 1 shows a diagram of the test plan; Table 2 shows a catheter protocol for the acetylcholine test and the protocol for the ultrasonic examination of the Arteria brachialis. Example 2 Oxypurinol Improves Nitric Oxide-Dependent Coronary and Peripheral Endothelial Function in Patients with Coronary Artery Disease The following methods were used in the study described in this Example. The study was approved by the Ethics Committeee of the Hamburg Medical Board and every patient had to give written informed consent. The trial was designed as an open label, non-randomized study, which included patients with angiographically documented CAD and preserved left ventricular function. Main exclusion criteria were unstable coronary artery disease or myocardial infarction within 2 weeks prior to study entry, previous coronary bypass surgery, significant valvular disease, an ejection fraction of <40%, hypotension, uncontrolled hypertension, creatinine 1.5 times upper limit of normal, hyperuricemia (> 351 μM in women and > 422 μM in men), current allopurinol intake or known allopurinol intolerance and intravenous heparin within the last 24h before the study. The index artery (left anterior descending artery or the circumflex artery) displayed a percentage stenosis of < 40%. Study Design Between February and August 2003, a total of 1536 patients, who underwent diagnostic cardiac catheterization and therapeutic coronary interventions at this institution, were screened for inclusion in the study. Twenty-two patients met the inclusion criteria and gave written informed consent. The majority of the study population was diagnosed for hypertension and hyperlipoproteinemia, and about 80% of the patients included were on ACE and HMG CoA reductase inhibitors, respectively (Table 3). Following coronary angiography (n=3) or percutaneous angioplasty (n=19), a 3F infusion catheter and a 0.018 inch Doppler flow wire (Cardiometrics, Moutain View, California) were positioned in the proximal left anterior descending (32%) or circumflex artery (68%) over a 7F guiding catheter. The patients received 7,000±2,000IU of unfractionated heparin at least 10 minutes prior to study entry and no additional heparin thereafter. Acetylcholine (ACh; Miochol, Ciba Vision) was infused in incremental concentrations (10^"7, 10^"6 and 10^"5 μM) at 2ml-min^"' for 3 minutes. At baseline and after each infusion, heart rate, blood pressure and average peak velocity were recorded, and a further angiography of the target vessel was performed as previously (18). Following an ACh washout phase of 10 minutes, oxypurinol (200mgT00ml^"') was infused over the femoral vein at 13 mg-min^"1. The study medication was prepared on-campus by dissolving oxypurinol (Cardiome Pharmaceuticals, Vancouver, Canada) in glucose 5% and sodium hydroxide to a final pH of 9.0. All preparations were used within 6 hours of preparation. Following oxypurinol infusion, measurements were repeated as above and intracoronary administration of nitroglycerine (200μg) was performed (Figure 3). Immediately before and after oxypurinol infusion, blood was sampled and plasma stored at -80°C for enzyme, metabolite and drug analysis. At day 30 after hospital discharge, all patients were followed up by telephone. Assessment of XO activity and plasma levels of oxypurinol, xanthine, hypoxanthine and uric acid Xanthine oxidase activity was determined by measurement of uric acid formation via HPLC with diode array detection. A chromatography elution scheme, using a 25 x 5 mm C18 column, was devised to permit the baseline resolution of added xanthine, uric acid and oxypurinol. This consisted of a 30 minute isocratic elution with KH₂PO₄ (300 mM, adjusted to pH 4.0)-methanol-acetonitrile-tetrahydrofuran (97.9:1:1:0.1, v/v). The flow rate was 1 πύVmin and the column temperature was maintained at 30^CC. An 8- channel electrochemical CoulArray detector (ESA Chelmsford, USA) with applied potentials of 0, 120, 220, 300, 575, 700, 800 and 900 mV was used for analysis. Every 5 samples, an internal standard mixture of oxypurinol, xanthine and uric acid was resolved chromatographically for calculating inhibitor and purine concentrations in patient plasma. All samples were run in duplicate, averaged and means combined for statistical analysis. The potentially confounding effects of plasma uricase activity were separately determined by addition of known concentrations of uric acid to plasma samples. Subsequent plasma analysis by HPLC-diode array detection monitoring revealed no detectable loss of uric acid over time. Measurement of coronary artery diameter and flow All angiograms were evaluated by an independent blinded investigator on a Siemens workstation for computerized quantitative coronary angiography with an automated contour detection (Siemens, Erlangen, Germany). Siemens Quantcor CCA Software version 4.0 was used. Adjustments were performed by manual correction if necessary (18, 19). Analysis of vessel lumenal diameter were performed at baseline, following ACh challenge before and after oxypurinol administration and after application of intracoronary nitroglycerine (200μg). Calculated indices of coronary blood flow included average peak velocity and luminal diameter 5 mm distally to the tip of the flow wire, as previously (20). Assessment of forearm flow mediated dilation Endothelium-dependent, flow-mediated dilation of the brachial artery was non-invasively determined as previously (21). In brief, images of the right brachial artery and pulsed-Doppler flow velocity signals were obtained with an ATL 7.5 to 12 MHz linear array transducer and an ATL HDI5000 ultrasound system (Philips, Da Best, The Netherlands). Assessment of brachial artery diameter and pulse-Doppler velocity signals was followed by 5 minutes of brachial artery occlusion and analysis of brachial artery diameter and pulse-Doppler velocity 60 seconds thereafter. Brachial artery diameters were analyzed via edge detection software (Brachial Analyzer, Medical Imaging Application, Iowa City, IA, USA), with flow- mediated dilation calculated as the percent change in brachial artery diameter in response to hyperemia. Reproducibility and repeatability was validated in 20 healthy volunteers, each of whom was examined and analyzed twice in a blinded fashion. Linear regression analysis revealed a correlation coefficient of 0.99. The average difference between determinations was 0.034±0.008mm (0.8±0.2% of the vessel diameter). To assess variability between the two studies, 10 healthy volunteers were examined twice. The average differences between two determinations by the same observer were 0.07±0.06mm for baseline diameter and 0.56±0.57% for flow-mediated dilation. Statistical analysis Statistical analyses were performed on an intention to treat basis. The primary endpoint of the study was the effect of oxypurinol on ACh dependent changes in coronary MLD and CBF. Changes in MLD and blood flow are given as percent change compared to baseline ± SEM. Oxypurinol plasma levels, XO activity, xanthine, hypoxanthine and uric acid plasma levels are given as mean ± SEM. Differences between groups were assessed by applying the paired Student's t-test. Differences of p<0.05 were considered statistically significant. Results Out of the 22 patients who were enrolled, 4 patients had to be excluded: One patient withdrew his informed consent and in 3 patients malpositioning or dislocation of the flow wire led to termination of the study. Of the 18 patients who completed the study protocol, 5 patients showed vasodilation in response to ACh 10^"5 μM (group I), whereas 13 patients revealed vasoconstriction in response to the highest dose of ACh administered (group II; ACh 10^"5 μM in n=l l and ACh 10^"6 μM in n=2, respectively). Administration of oxypurinol was tolerated by every patient without notification of any adverse event during the hospital stay. Within 30 days, only one patient underwent reangiography without need for subsequent revascularization. Plasma levels of oxypurinol and purine metabolites Following infusion of oxypurinol, plasma levels increased from 0.06 ± 0.04 to 114 ± 33 μM (Table 4; pθ.001). Accordingly, plasma XO activity was reduced by 63% (p<0.01, Figure 4). Xanthine levels remained unchanged before and after oxypurinol administration, whereas hypoxanthine levels increased following oxypurinol infusion (Table 4; p<0.05 for uric acid and p<0.001 for hypoxanthine, respectively). Quantitative coronary angiography In patients, who showed vasodilation in response to ACh (group I), oxypurinol infusion had no effect on ACh-dependent vasoreactivity (+2.8±4.2 vs. 5.2±0.7% change to baseline at ACh 10^"5, p>0.05; Figure 5a) nor CBF (135±75 vs. 154±61% change to baseline, p>0.05; Figure 5b). However, in patients displaying vasoconstriction in response to the highest dose of ACh (group II) oxypurinol markedly attenuated ACh-dependent vasoconstriction (-23±4 vs. -15±4% change to baseline, p<0.05; Figure 1, Figure 5c) and increased CBF (16±17% vs. 62±18% change to baseline, p<0.05; Figure 2, Figure 5d). Eight consecutive patients (group I n=2; group II n=6) also underwent assessment of flow-mediated dilation and hyperemic brachial artery flow before the procedure and following the coronary intervention. Flow dependent dilation of the brachial artery increased from 5.1±1.5 before to 7.6±1.5% after oxypurinol administration (p<0.05; Figure 6). There was no correlation between oxypurinol-induced changes in endothelial function of coronary and peripheral conductance vessels. Discussion The present studies reveal a significant impact of XO-derived reactive species on NO-dependent signaling in the coronary and peripheral vasculature of patients with stable coronary disease. Inhibition of XO via systemic administration of oxypurinol to patients a) attenuated Ach-induced coronary vasoconstriction (Figure 5c), b) improved myocardial perfusion (Figure 5d) and c) ameliorated peripheral endothelial dysfunction (Figure 6). Xanthine oxidase is abundant in vascular endothelium and plasma of CAD patients (22) (Figure 4). Circulating XO binds avidly to endothelial cells and undergoes transcytosis into the subendothelial space (23, 24). Conditions inherent in CAD enhance XO gene expression in endothelial cells, including hypoxia and turbulent flow (25, 26). In atherosclerotic plaques, uric acid levels were found to be elevated up to 6- fold, reflecting accelerated purine oxidation and suggesting that local manifestations of XO oxidant production are not necessarily reflected by systemic levels of XO metabolites (27). When converted into its oxidase form via partial proteolysis and intramolecular thiol oxidation, xanthine oxidoreductase reduces molecular oxygen to both superoxide and hydrogen peroxide during purine oxidation (28). The endothelial distribution of XO and the oxidative milieu that this enzyme generates predisposes vascular NO catabolism. Xanthine oxidase derived superoxide rapidly reacts at diffusion- limited rates with NO (2 x 10¹⁰ mol^"1 sec^"1) to yield the secondary oxidant peroxynitrite (ONOO^") (29), thus impairing NO signaling. The vasodilatory actions of oxypurinol can also reflect attenuated catalytic activity of another hydrogen peroxide-dependent NO-oxidizing enzyme, leukocyte myeloperoxidase (MPO). This enzyme catalytically consumes NO and is distributed in the vessel wall of CAD patients in a manner similar to XO. By virtue of oxypurinol-dependent inhibition of XO, local steady state concentrations of not only superoxide, but also hydrogen peroxide are suppressed, thus limiting multiple mechanisms of catalytic NO catabolism in this vascular region critical for NO-dependent vascular relaxation (30-32). Xanthine oxidase-dependent oxidative inhibition of vascular function has been observed in animal models of sickle cell disease, ischemia-reperfusion injury, hypertension, atherosclerosis and hypercholesterolemia (10,-13, 22, 23, 33, 34). Clinical studies of peripheral vascular blood flow corroborated these findings in patients with hypercholesterolemia, cardiomyopathy, diabetes and smokers (28). However, all of these investigations studied the effects of XO inhibition in the systemic circulation, thus the clinically- significant contribution of XO to impaired coronary endothelial function has remained elusive. The present observations reveal that XO-derived reactive species catalyze NO catabolism in the coronary circulation and that oxypurinol-mediated inhibition of XO attenuates Ach-dependent vasoconstriction of conductance vessels (Figure 5c), and profoundly increases cardiac perfusion. These observations also strongly support that XO is distributed in the microcirculation (Figure 5d), a critical determinant of resistance to cardiovascular and systemic blood flow (30). Following intravenous infusion of oxypurinol, plasma XO activity was reduced by about 65% (Figure 4). Thus the contributory role of XO to coronary NO catabolism may still be underestimated and higher levels of oxypurinol would potentially improve coronary endothelial function even further. Particularly, since studies on endothelial bound, immobilized XO suggest an even higher inhibition constant for this enzyme. Moreover, all patients received intra-arterial heparin before initiation of the study. Since heparin has been shown to release vessel bound XO into the plasma, NO catabolism by XO may be even more pronounced in the absence of heparin (35). Interestingly, oxypurinol displayed vasodilatory effects although the majority of patients received treatment with angiotensin converting enzyme and HMG CoA reductase inhibitors, agents which have been shown to improve vascular NO bioavailabihty by reducing vascular superoxide levels and stimulating NO release. Thus XO inhibition represents an independent and additive mechanism that increases vascular NO bioavailabihty, an event that translates into improved endothelial function in CAD (36, 37). XO inhibition by oxypurinol not only attenuated vasomotor dysfunction within the coronary circulation, but also improved flow-dependent vasodilation of the brachial artery (Figure 6). While the study size tested for both parameters was too small to prove a significant correlation between coronary and forearm vasoreactivity, the favorable effects observed for both parameters is concordant with studies demonstrating the predictive power of invasive and non-invasive assessment of endothelial function on the prognosis of patients with coronary artery disease (38, 39). The current study had a small size and was a non-randomized and non-blinded design. However, given the significant improvement of coronary endothelial function in patients a), concurrently undergoing angiotensin converting enzyme and HMG CoA reductase inhibition, b) treated with heparin and c) possibly having submaximal inhibition of XO, these results affirm two key points. First, there is a pathophysiological role for XO-derived reactive oxygen species in coronary disease and second, inhibition of XO restores more normal vascular function in coronary disease patients. Summary Coronary and peripheral (brachial artery) endothelial function was assessed in 22 patients (pts; 65±8 years, 80% male) with angiographically-documented CAD, preserved left ventricular function and non- elevated uric acid levels (233±10μM). Patients received incremental doses of intracoronary acetylcholine (ACh, 10^"7 to 10^"5μM) and minimal lumen diameter (MLD) and coronary blood flow (CBF) were assessed before and after intravenous administration of oxypurinol (200mg). Oxypurinol inhibited plasma XO activity 63% (0.051 ± 0.001 vs 0.019 ± 0.005 μU/mg protein; p<0.01). Out of 22 pts., 18 completed the protocol. Five pts. revealed vasodilation in response to the highest dose of ACh administered (group I), whereas Ach- evoked vasoconstriction in 13 pts. (group II). In group I, the increase in MLD remained unchanged following oxypurinol (2.8±4.2 vs. 5.2±0.7% at ACh 10^"5μ , p>0.05) and the increment in CBF was not increased following oxypurinol (135±75 vs 154±61% at ACh 10^"5μM, p>0.05). In group II, oxypurinol markedly attenuated Ach-induced vasconstriction (-23±4 vs -15±4% at ACh 10^"5μM, p<0.05) and significantly increased CBF (16±17% vs 62±18% at ACh 10^"5μM, p<0.05). Endothelial function of forearm conductance vessels, as assessed by flow mediated dilation in 8 consecutive patients, significantly increased in response to oxypurinol (5.1±1.5 vs 7.6±1.5%, p<0.05). Conclusion Oxypurinol inhibition of XO improves the coronary and peripheral vascular endothelial dysfunction that is a hallmark of patients with CAD. These observations reveal that XO-derived reactive oxygen species significantly contribute to impaired vascular NO bioavailabihty in CAD and that XO inhibition represents an additional treatment concept for inflammatory vascular diseases that deserves further investigation. In patients with CAD and normal LV-Fx, oxypurinol attenuated Ach-induced coronary vasoconstriction and increased coronary blood flow in patients with endothelial dysfunction. Systemic administration of oxypurinol also improved peripheral vasomotor function.

The present invention is not to be limited in scope by the specific embodiments described herein, since such embodiments are intended as but single illustrations of one aspect of the invention and any functionally equivalent embodiments are within the scope of this invention. Indeed, 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 accompanying drawings. Such modifications are intended to fall within the scope of the appended claims. All publications, patents and patent applications referred to herein are incorporated by reference in their entirety to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference in its entirety. All publications, patents and patent applications mentioned herein are incorporated herein by reference for the purpose of describing and disclosing the compounds, methods, etc. which are reported therein which might be used in connection with the invention. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.

Table 1 Diagram of the test plan

1. BMI: Body mass index 2. Diagnostic coronary angiography can be done as much as 14 days before Visit 1. 3. PCI; Percutaneous coronary intervention (PTCA, Stent implantation, Rotablation) (although PCI occurs after inclusion in the study, it is not part of the study) 4. Laboratory measurements: Determination of plasma concentrations of creatinine, urea, potassium, total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides. Also, once before intervention: C-reactive protein, uric acid, homocysteine, folic acid, total cholesterol, HDL cholesterol, triglycerides.

Table 2 Catheter protocol

Catheter protocol : Acetylcholine test

ANGIO: 1 2 3 4 5 6

INFUSION: BL Al A2 A3

BOLUS: NTG

BL Dextrose 5% x 3 Minutes

Al Acetylcholine 10^"7 x 3 Minutes A2 Acetylcholine 10^"6 x 3 Minutes A3 Acetylcholine 10^"5 x 3 Minutes

NTG: Bolus intracoronary, 0.2mg

Solutions

Substances: - Miochol-E (Acetylcholine chloride 20mg/2ml; Ciba Vision) 1 mole Acetylcholine = 146g 1 mole Acetylcholine chloride = 181,68 g (lg Ach Cl = 5.5 * 10^"3 mole) - NaC10.9%

Stock solution 1 : 2 ml Miochol-E + 98 ml NaCl 0.9% (=0.2 mg/ml) Stock solution 2: 9 ml Stock solution 1 + 91 mlNaCl 0.9% (= 18.0 μg/ ml)

Perfusor syringe 1 : 40 ml Stock solution 2 (Ach [acetylcholine] 10 ) (= 18.0 μg/ ml)

Perfusor syringe 2: 8ml from Perfusor syringe 1 4- 32ml NaCl 0.9% (Ach 10^"6) (= 3.6 μg/ ml)

Perfusor syringe 3: 4ml from Perfusor syringe 2 + 36ml NaCl 0.9% (Ach 10^"7) (= 0.36 μg/ ml)

Infusion duration: 3 Minutes Infusions rate: 2ml/ min (Perfusor setting 120mV h)

Estimated coronary blood flow: 80ml/ min. Dilution for 2ml min Infusion = 1 :40

Perfusor 3 infuses at 0.72μg/min. Local concentration = 0.5 -10^"7mol/l Ach Cl Perfusor 2 infuses at 7.2 μg/min. Concentration = 0.5 • 10^"6mol l Ach Cl Perfusor 1 infuses at 36 μg/min Local concentration = 0.5 • 10^"5moVl Ach Cl Table3 Baseline clinical characteristics of study population

Table 4. Plasma levels of purine metabolites and oxypurinol before and after oxypurinol administration

Data from n=20 are presented as mean±SEM.

References

1. Libby P. Inflammation in atherosclerosis. Nature. 2002;420:868-74.

2. Moro MA, Russel RJ, Cellek S, et al. cGMP mediates the vascular and platelet actions of nitric oxide: confirmation using an inhibitor of the soluble guanylyl cyclase. Proc Natl Acad Sci U S A. 1996;93:1480-5.

3. Bouloumie A, Bauersachs J, Linz W, et al. Endothelial dysfunction coincides with an enhanced nitric oxide synthase expression and superoxide anion production. Hypertension. 1997;30:934-41.

4. Harrison D, Griendling KK, Landmesser U, et al. Role of oxidative stress in atherosclerosis. Am J Cardiol. 2003;91 :7A-l lA.

5. Munzel T, Sayegh H, Freeman BA, et al. Evidence for enhanced vascular superoxide anion production in nitrate tolerance. A novel mechanism underlying tolerance and cross-tolerance. J Clin Invest. 1995;95:187-94.

6. Griendling KK, FitzGerald GA. Oxidative stress and cardiovascular injury: Part II: animal and human studies. Circulation. 2003;108:2034-40.

7. Sydow K, Daiber A, Oelze M, et al. Central role of mitochondrial aldehyde dehydrogenase and reactive oxygen species in nitroglycerin tolerance and cross-tolerance. J Clin Invest. 2004; 113:482- 9.

8. Freedman JE, Keaney JF, Jr. Nitric oxide and superoxide detection in human platelets. Methods Enzymol. 1999;301:61-70.

9. Munzel T, Feil R, Mulsch A, et al. Physiology and pathophysiology of vascular signaling controlled by guanosine 3',5'-cyclic monophosphate-dependent protein kinase [corrected]. Circulation. 2003;108:2172-83.

10. Asian M, Ryan TM, Adler B, et al. Oxygen radical inhibition of nitric oxide-dependent vascular function in sickle cell disease. Proc Natl Acad Sci U S A. 2001;98:15215-20.

11. Meneshian A, Bulkley GB. The physiology of endothelial xanthine oxidase: from urate catabolism to reperfusion injury to inflammatory signal transduction. Microcirculation. 2002;9:161-75.

12. Ohara Y, Peterson TE, Harrison DG. Hypercholesterolemia increases endothelial superoxide anion production. J Clin Invest. 1993;91:2546-51.

13. White CR, Darley-Usmar V, Berrington WR, et al. Circulating plasma xanthine oxidase contributes to vascular dysfunction in hypercholesterolemic rabbits. Proc Natl Acad Sci U S A. 1996;93:8745- 9.

14. Guthikonda S, Sinkey C, Barenz T, et al. Xanthine oxidase inhibition reverses endothelial dysfunction in heavy smokers. Circulation. 2003;107:416-21.

15. Farquharson CA, Butler R, Hill A, et al. Allopurinol improves endothelial dysfunction in chronic heart failure. Circulation. 2002;106:221-6.

16. Butler R, Morris AD, Belch JJ, et al. Allopurinol normalizes endothelial dysfunction in type 2 diabetics with mild hypertension. Hypertension. 2000;35:746-51.

17. Cardillo C, Kilcoyne CM, Cannon RO, 3rd, et al. Xanthine oxidase inhibition with oxypurinol improves endothelial vasodilator function in hypercholesterolemic but not in hypertensive patients. Hypertension. 1997;30:57-63. 18. Effect of nifedipine and cerivastatin on coronary endothelial function in patients with coronary artery disease: the ENCORE I Study (Evaluation of Nifedipine and Cerivastatin On Recovery of coronary Endothelial function). Circulation. 2003;107:422-8.

19. Koster R, Vieluf D, Kiehn M, et al. Nickel and molybdenum contact allergies in patients with coronary in-stent restenosis. Lancet. 2000;356:1895-7.

20. Doucette JW, Corl PD, Payne HM, et al. Validation of a Doppler guide wire for intravascular measurement of coronary artery flow velocity. Circulation. 1992;85 : 1899-911.

21. Levine GN, Frei B, Koulouris SN, et al. Ascorbic acid reverses endothelial vasomotor dysfunction in patients with coronary artery disease. Circulation. 1996;93:1107-13.

22. Spiekermann S, Landmesser U, Dikalov S, et al. Electron spin resonance characterization of vascular xanthine and NAD(P)H oxidase activity in patients with coronary artery disease: relation to endothelium-dependent vasodilation. Circulation. 2003;107:1383-9.

23. Houston M, Estevez A, Chumley P, et al. Binding of xanthine oxidase to vascular endothelium. Kinetic characterization and oxidative impairment of nitric oxide-dependent signaling. J Biol Chem. 1999;274:4985-94.

24. Asian M, Ryan TM, Townes TM, et al. Nitric oxide-dependent generation of reactive species in sickle cell disease. Actin tyrosine induces defective cytoskeletal polymerization. J Biol Chem. 2003;278:4194-204.

25. Terada LS, Piermattei D, Shibao GN, et al. Hypoxia regulates xanthine dehydrogenase activity at pre- and posttranslational levels. Arch Biochem Biophys. 1997;348:163-8.

26. McNally JS, Davis ME, Giddens DP, et al. Role of xanthine oxidoreductase and NAD(P)H oxidase in endothelial superoxide production in response to oscillatory shear stress. Am J Physiol Heart Circ Physiol. 2003;285:H2290-7.

27. Patetsios P, Song M, Shutze WP, et al. Identification of uric acid and xanthine oxidase in atherosclerotic plaque. Am J Cardiol. 2001;88:188-91, A6.

28. Berry CE, Hare JM. Xanthine oxidoreductase and cardiovascular disease - molecular mechanisms and pathophysiologic implications. J Physiol. 2003.

29. Beckman JS, Beckman TW, Chen J, et al. Apparent hydroxyl radical production by peroxynitiite: implications for endothelial injury from nitric oxide and superoxide. Proc Natl Acad Sci U S A. 1990;87:1620-4.

30. Brown JM, Terada LS, Grosso MA, et al. Xanthine oxidase produces hydrogen peroxide which contributes to reperfusion injury of ischemic, isolated, perfused rat hearts. J Clin Invest. 1988;81:1297-301.

31. Eiserich JP, Baldus S, Brennan ML, et al. Myeloperoxidase, a leukocyte-derived vascular NO oxidase. Science. 2002;296:2391-4.

32. Baldus S, Eiserich JP, Mani A, et al. Endothelial transcytosis of myeloperoxidase confers specificity to vascular ECM proteins as targets of tyrosine nitration. J Clin Invest. 2001;108:1759- 70.

33. Mervaala EM, Cheng ZJ, Tikkanen I, et al. Endothelial dysfunction and xanthine oxidoreductase activity in rats with human renin and angiotensinogen genes. Hypertension. 2001;37:414-8. 34. Nakazono K, Watanabe N, Matsuno K, et al. Does superoxide underlie the pathogenesis of hypertension? Proc Natl Acad Sci U S A. 1991;88:10045-8.

35. Landmesser U, Spiekermann S, Dikalov S, et al. Vascular oxidative stress and endothelial dysfunction in patients with chronic heart failure: role of xanthine-oxidase and extracellular superoxide dismutase. Circulation. 2002;106:3073-8.

36. Anderson TJ, Meredith IT, Yeung AC, et al. The effect of cholesterol-lowering and antioxidant therapy on endothelium-dependent coronary vasomotion. N Engl J Med. 1995;332:488-93.

37. Mancini GB, Henry GC, Macaya C, et al. Angiotensin-converting enzyme inhibition with quinapril improves endothelial vasomotor dysfunction in patients with coronary artery disease. The TREND (Trial on Reversing ENdothelial Dysfunction) Study. Circulation. 1996;94:258-65.

38. Schachinger V, Britten MB, Zeiher AM. Prognostic impact of coronary vasodilator dysfunction on adverse long-term outcome of coronary heart disease. Circulation. 2000;101:1899-906.

39. Gokce N, Keaney JF, Jr., Hunter LM, et al. Predictive value of noninvasively determined endothelial dysfunction for long-term cardiovascular events in patients with peripheral vascular disease. J Am Coll Cardiol. 2003;41:1769-75.

40. Balligand JL, Kelly RA, Smith TW. Cardiac endothelium and tissue growth. Prog Cardiovasc Dis. 1997; 39:351-60.

41. Moncada, S., and Higgs, A. The L-arginine-nitric oxide pathway. N. Engl. J. Med. 1993; 329:2002- 12

42. von der Leyen HE, Gibbons GH, Morishita R, Lewis NP, Zhang L, Nakajima M, Kaneda Y, Cooke JP, Dzau VJ. Gene therapy inhibiting neointimal vascular lesion: in vivo transfer of endothelial cell nitric oxide synthase gene. Proc. Natl. Acad. Sci. U. S.A. 1995; 92:1137-41

43. Channon, K.M. et al. In vivo gene transfer of nitric oxide synthase enhances vasomotor function in carotid arteries from normal and cholesterol-fed rabbits. Circulation 1998; 98: 1905-11.

44. von der Leyen HE, Dzau VJ. Therapeutic potential of nitric oxide synthase gene manipulation. Circulation 2000; 103:2760-5

45. Thomas, D.D., Liu, X., Kantrow, S., Lancaster, J.R. Jr. The biological lifetime of nitric oxide: Implications for the perivascular dynamics of NO and 02. Proc Natl Acad Sci U S A. 2001. 98: 355-60

46. Houston, M., Estevez, A., Chumley, P., Asian, M., Marklund, S., Parks, D.A., and Freeman, B.A. Binding of xanthine oxidase to vascular endothelium. Kinetic characterization and oxidative impairment of nitric oxide-dependent signaling. J. Biol. Chem. 1999; 274:4985-94

47. Butler R, Morris AD, Belch JJ, Hill A, Struthers AD. Allopurinol normalizes endothelial dysfunction in type 2 diabetics with mild hypertension. Hypertension. 200;35:746-51

48. Cardillo C, Kilcoyne CM, Cannon RO 3rd, Quyyumi AA, Panza JA. Xanthine oxidase inhibition with oxypurinol improves endothelial vasodilator function in hypercholesterolemic but not in hypertensive patients. Hypertension. 1997; 30:57-63

49. Castelli P, Condemi AM, Brambillasca C, Fundaro P, Botta M, Lemma M, Vanelli P, Santoli C, Gatti S, Riva E. Improvement of cardiac function by allopurinol in patients undergoing cardiac surgery. J Cardiovasc Pharmacol. 1995; 25:119-25

Claims

What is claimed is:

1. A method for improving coronary and peripheral endothelial function in a patient comprising inhibiting production or activity of, or reducing the amount of xanthine oxidase-derived reactive species in coronary and/or peripheral vasculature in the patient.

2. A method of preventing and/or treating coronary heart disease or coronary artery disease in a patient comprising inhibiting production or activity of, or reducing the amount of xanthine oxidase- derived reactive species in coronary vasculature in the patient.

3. A method for modulating activity of an enzyme dependent on xanthine oxidase-derived reactive species, in particular leukocyte myeloperoxidase, comprising directly or indirectly inhibiting production or activity of, or reducing the amount of xanthine oxidase-derived reactive species.

4. A method for increasing bioavailabihty of endothelial derived vascular NO, reducing NO catabolism in the coronary vasculature, inhibiting catalytic NO catabolism in a vascular region that requires NO for NO-dependent vascular relaxation, and/or increasing NO-signalling in the coronary vasculature, in particular the coronary vasculature, comprising inhibiting the production or function of, or reducing the amount of, xanthine oxidase derived-reactive species in the coronary vasculature.

5. A method of any preceding claim wherein inhibition or reduction of xanthine oxidase-derived reactive species is achieved by inliibiting xanthine oxidase.

6. A method of claim 5 wherein xanthine oxidase is inhibited by a xanthine oxidase inhibitor.

7. A method of any preceding claim wherein the xanthine oxidase-derived reactive species are superoxide, hydrogen peroxide, and/or peroxynitrite.

8. A method of preventing and/or treating cardiovascular disease associated with impaired endothelial function in a patient comprising administering an agent that inhibits the production or function of, or reduces the amount of, xanthine oxidase-derived reactive species in the coronary vasculature.

9. A method for preventing and/or treating a coronary heart disease, coronary artery disease, coronary artery dysfunction, or coronary endothelial dysfunction in a patient comprising administering an agent in an effective amount that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived reactive species in the coronary vasculature.

10. A method of claim 9 for preventing and/or treating coronary heart disease.

11. A method of claim 9 for preventing and/or treating coronary artery disease.

12. A method of claim 10 or 11 wherein the agent enhances NO-dependent signalling in the coronary vasculature, and/or inhibits NO catabolism in a vascular region that requires NO for NO-dependent vascular relaxation.

13. A method for treating and/or preventing a cardiovascular disease with impaired cardiac blood flow, in particular impaired coronary artery blood flow or reduced coronary artery diameter, in a patient, comprising administering an agent in an effective amount that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO-dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived reactive species in the coronary vasculature.

14. A method for restoring ability of the coronary artery to increase in diameter in a patient comprising administering an agent in an effective amount that enhances NO-dependent signalling in the coronary vasculature, inhibits NO catabolism in the coronary vasculature that requires NO for NO- dependent vascular relaxation, and/or inhibits or reduces xanthine oxidase-derived oxygen species in the coronary vasculature.

15. A method for treatment and/or prevention of coronary heart disease (CHD) in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

16. A method for treatment and/or prevention of coronary artery disease (CAD) in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

17. A method for treating coronary heart disease or coronary artery disease in a mammal, comprising selecting a mammal for treatment of coronary heart disease or coronary artery disease that is suffering from, susceptible to, or that has suffered coronary heart disease or coronary artery disease and administering to the selected mammal a composition comprising an effective amount of a xanthine oxidase inhibitor.

18. A method for preventing and/or treating coronary artery dysfunction in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

19. A method for improving cardiac blood flow, more particularly coronary artery blood flow in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

20. A method for increasing coronary artery diameter in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

21. A method for improving endothelium-dependent vasodilation in a patient comprising reducing vascular steady state superoxide levels by administering an effective amount of a xanthine oxidase inhibitor.

22. A method for attenuating vasomotor dysfunction within the coronary circulation of a patient comprising administering an effective amount of a xanthine oxidase inhibitor.

23. A method for restoring the ability of the coronary artery to increase in diameter size in a patient comprising administering to the patient an effective amount of a xanthine oxidase inhibitor.

24. A method of normalizing abnormal levels of enzymes and/or other bio-markers indicative of heart disease comprising administering an effective amount of a xanthine oxidase inhibitor.

25. A method of claim 24 wherein the enzymes are dependent on reactive species such as xanthine oxidase-derived reactive species.

26. A method of claim 25 wherein the enzymes are hydrogen peroxide dependent NO-oxidizing enzymes including but not limited to leukocyte myeloperoxidase.

27. A method of any preceding claim wherein the xanthine oxidase inhibitor is oxypurinol.

28. A method for treating coronary heart disease or coronary heart disease in a mammal suffering from, susceptible to, or that has suffered such disease comprising administering to the mammal a composition comprising a therapeutically effective amount of allopurinol or oxypurinol.

29. A method for treating heart failure in a mammal suffering from or that has suffered coronary artery disease comprising administering to the mammal a composition comprising an effective amount of oxypurinol.

30. A pharmaceutical composition comprising a xanthine oxidase inhibitor in an effective amount to provide a beneficial effect to prevent and/or treat a vascular disease associated with xanthine oxidase-derived reactive species, and a pharmaceutically acceptable carrier, excipient, vehicle, or diluent.

31. A pharmaceutical composition comprising a xanthine oxidase inhibitor in a concentration or dose sufficient to increase NO signalling, decrease NO catabolism, or inhibit or reduce the amount of xanthine oxidase-derived species in coronary vasculature, in particular coronary microcirculation.

32. A pharmaceutical composition for preventing and/or treating a vascular and/or cardiovascular disease comprising two or more of a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more agent that improves NO bioavailabihty.

33. A pharmaceutical composition of any preceding claim wherein the xanthine oxidase inhibitor is oxypurinol.

34. A combination therapy for treating and/or preventing coronary heart disease, coronary artery disease, coronary artery dysfunction, or coronary endothelial dysfunction comprising administering two or more of a xanthine oxidase inhibitor, a glycosaminoglycan, and one or more agent that improves NO bioavailabihty.

35. A combination therapy of claim 34 wherein the xanthine oxidase inhibitor is oxypurinol.

36. A kit for carrying out a method as claimed in any preceding claim.