AU782001B2 - Methods for treating cardiogenic shock using a nitric oxide synthase inhibitor - Google Patents

Description

1 METHODS FOR TREATING CARDIOGENIC SHOCK USING A NITRIC OXIDE SYNTHASE INHIBITOR FIELD OF THE INVENTION The present invention relates to pharmaceutical compositions comprising nitric oxide synthase inhibitors which may be used to treat certain cardiac conditions.

BACKGROUND OF THE INVENTION Nitric oxide synthase inhibitors Nitric oxide a potent vasodilator, functions as a neurotransmitter in a variety of physiological processes. The biosynthesis of nitric oxide from Larginine is catalyzed by the enzyme nitric oxide synthase (NOS), which exists as three major enzyme isoforms including the constitutive endothelial cell enzyme (eNOS), which is involved in the regulation of smooth muscle relaxation and has a role in the physiological control of blood pressure, the neuronal enzyme (nNOS), involved in brain development and memory, and an inducible enzyme (iNOS) produced by activated macrophages during an immune response, e.g. in response to endotoxin or cytokines. Expression of NOS leads to the production of large quantities of NO and profound vasodilation.

Production of excess NO by the NOS isoforms is related to several diseases such as stroke, Alzheimer and other neurodegenerative diseases, septic shock, 25 inflammatory arthritis and colitis. Septic shock results from the action of endotoxins or other products of infectious agents on the vascular system causing peripheral arteriolar vasodilation which leads to a hyperdinamic state with low 3 m* *o Y \MartNKI NO DELETES4237-00A doc SWO 1/00195 Page 3 of 24 WO 01/00195 PCT/IL00/00369 -2systemic vascular resistance, high cardiac output, hypotension and inadequate tissue perfusion.

N'-substituted-L-arginine compounds are known NOS inhibitors. Examples of such NOS inhibitors include N'-monomethyl-L-arginine (L-NMMA) and the analogues thereof wherein ethyl, propyl, allyl or propargyl replace the methyl radical, and N"-nitro-L-arginine methyl ester (L-NAME).

L-NMMA blocks the intrinsic production of NO and therefore is one of the most efficient vasoconstrictors known. It was examined previously in several shock situations. In a small study of patients with septic shock L-NMMA was shown to increase blood pressure, peripheral resistance, central venous pressure, and pulmonary vascular resistance. L-NMMA was further shown to improve hemodynamics in experimental hemorrhagic shock although some early reports have doubted its effect on outcome in septic shock.

A review of the literature shows conflicting data in different animal models regarding the effects of L-NMMA on coronary blood flow and myocardial contractility.

The effect of L-NMMA on coronary blood flow is controversial. In humans, L-NMMA decreases flow depended epicardial coronary vasodilatation; however it does not reduce arteriolar vasodilatation in response to pacing This finding implies that L-NMMA has little effect on coronary resistance arteries and therefore probably only minor influenceU durin.lg iscICemia. FulrcemnuiE, ii was receniiy shown that L-NMMA administration following ischemia actually increases coronary blood flow thus improving contractility The effects of nitric oxide and L-NMMA on myocardial contractility are also controversial. Recent experimental data on both human and animal tissue culture, and in animal models, have shown that nitric oxide significantly decreases myocardial contractility, an effect that can be reversed with L-NMMA administration Furthermore, following ischemia/reperfusion in animals sustained inhibition of nitric oxide by L-NMMA improves myocardial function.

WO 01/00195 WO 01/00195 PCT/IL00/00369 -3- Therefore, it is possible that L-NMMA administration may increase cardiac contractility and function, especially after ischemia/reperfusion.

Furthermore, it is possible that some of L-NMMA's positive effects are related to its modulatory effects on sympathetic activity. In doses comparable to those used in the present invention (in humans), L-NMMA has been shown to have a sympathoexcitatory effect In a dog model, nitric oxide has been shown to increase vagal inhibition (which could be blocked by L-NMMA) In a further study, L-NMMA was shown to augment the positive inotropic response to the beta-adrenergic stimulus of dobutamine in patients with congestive heart failure, o1 but not in normal subjects Finally, it was recently suggested that NO might have some negative metabolic effects on the ischemic myocardium. In animal models it was demonstrated that NO donors decrease glucose uptake and glycolytic flux, an effect that can be blocked by NOS inhibitors (11).

Acute Coronary Syndrome An acute coronary syndrome is a group of syndromes including acute myocardial infarction (MI) either Q wave or non-Q wave and unstable angina pectoris. The common mechanism of these diseases is the acute obstruction of an epicardial coronary artery caused by fissure and rupture of a coronary plaque complicated by coronary thrombosis enhancing the obstruction. In this setting the rnrnnanrv blnM flow distnly tv tthis obsrhtrtion is cmpromised. 1Normally, the coronary blood flow is regulated by microvascular (arteriolar) tone increasing blood flow regionally as a function of demand (usually referred to as autoregulation). However, after an acute obstruction, the distal coronary pressure is significantly decreased, therefore arterioles are fully dilated to allow for maximal blood flow. In this setting, further arteriolar dilatation is not possible and coronary autoregulation is lost. Therefore, in coronary bed distal to the coronary obstruction induced by a coronary event blood flow is highly dependent on optimal coronary perfusion.

Page 4 of 24 WO 01/00195 Page 5 of 24 WO01/00195 PCT/ILOO/00369 -4- Cardiogenic Shock Cardiogenioc shock, one of the possible complications of myocardial infarction, is an extreme situation in which decreased cardiac performance (usually induced by an acute coronary event) causes decreased perfusion to the vascular bed of critical organs including the heart, brain and kidneys in a way that compromises their function. When characterized by hypotension, tachycardia, mental confusion and cold extremities, it carries a grave prognosis.

The ideal pharmacological treatment of cardiogenic shock is elusive. In the past few decades a number of new treatment modalities have been developed such as treatment with catecholamines, e.g. dopamine and dobutamine. However, none has produced significant long-standing clinical benefit. This may be attributed to the significant positive inotropic and chonotropic effect of these drugs increasing the mismatch between the myocardial demand and the decreased, fixed coronary reserve leading to further deterioration in myocardial viability and function and inducing arrhythmias.

Furthermore, cardiac function measurements (Cardiac Index, Ejection Fraction) in the range found in the present invention, as well as previous studies of patients with cardiogenic shock, are usually compatible with life, and sometimes near normal function in patients with chronic rather than acute heart failure. This implies that mal-adaptive mechanisms rather than the decreased cardiac function n .r m, nnt,-r tP t hD g 4 A per se may contibute to the high rate of morbit anu ImoUta illy in cardiogenic shock.

L-NMMA, one of the most potent vasoconstrictors known, has been examined in various shock situations including septic, hemorrhagic, and anaphylactic shock However, since NO is known to induce coronary vasodilatation, L-NMMA was not examined in cardiogenic shock due to concerns regarding a possible ischemic effect.

The discussion of the background to the invention herein is included to explain the context of the invention. This is not to be taken as an admission that any of the material referred to was published, known or part of the common general knowledge in Australia as at the priority date of any of the claims.

Throughout the description and claims of the specification the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives, components, integers or steps.

go•• *3 Y \MaryNKI NO DELETE MR\54237-00 do WO 01/00105 Page 6 of 24 WO 01/00195 PCT/IL00100369 SUMMARY OF THE INVENTION The present invention is based on the observation that decreased blood pressure and especially any decrease in systolic hblood npresur to below 120 rmmH systolic (which is regarded usually as normal blood pressure) is deleterious during acute coronary syndromes, and especially during and immediately after reperfusion therapy either by thrombolytic therapy or mechanical revascularization i.e.

percutaneous transluminal coronary angiography (PTCA), percutaneous transluminal coronary revascularization (PTCR) or stenting. Therefore, the administration of an agent that will produce an increase in blood pressure to beyond 120 mmHg in such patients, in particular when the decrease in blood pressure is symptomatic or associated with shock, may improve clinical patient outcome characterized by a decrease of myocardial damage and, thereby decreasing mortality rate and late complications of heart failure. The use of previously known drugs including inotropic amines, milrinone, amrinone, etc, to achieve this aim, has not produced any beneficial effect since these drugs increase cardiac demand as their main mechanism of action.

It has now been found, in accordance with the present invention, that nitric oxide synthase inhibitors can be effectively used for this purpose.

The present invention thus relates to a pharmaceutical composition comprising a nitric oxide synthase inhibitor and a pharmaceutically acceptable carrier for the treatment of decreased blood pressure to below 120 mmHg systolic, symptomatic hypotension, cardiogenic shock occurring during an acute coronary syndrome or cardiogenic shock occurring during or after coronary artery bypass surgery or during or after any other cardiac surgery, particularly during or after reperfusion therapy or due to myocarditis.

The pharmaceutical composition of the invention is intended for administration in low dose, for example 0.5-1.5 mg/kg body weight/hour, preferably 1 mg/body weight/hour, to increase blood pressure to the high-normal range therefore improving coronary perfusion pressure, especially in reperfused myocardial regions, without increasing cardiac demand.

wo 0I gC0102 Page 7 of 24 WO 01/00195 PCT/IL00/00369 -6- Any nitric oxide synthase inhibitor may be used according to the invention, including, but not being limited to, a Nw-substituted-L-arginine compound such as N'"-monomethyl-L-arginine (L-NMMA) or an analogue thereof wherein ethyl, propyl, allyl or propargyl replaces the methyl radical, and N'-nitro-L-arginine methyl ester (L-NAME). In a preferred embodiment, the nitric oxide synthase inhibitor is L-NMMA. This compound exhibited favorable clinical and hemodynamic effects on patients with cardiogenic shock, in the clinical study carried out according to the invention.

In another aspect, the invention relates to the use of a nitric oxide synthase inhibitor for the preparation of a medicament for the treatment of decreased blood pressure to below 120 mmHg systolic, symptomatic hypotension, cardiogenic shock occurring during an acute coronary syndrome or cardiogenic shock occurring during or after coronary artery bypass surgery or during or after any other cardiac surgery, particularly during or after reperfusion therapy or due to myocarditis.

In still another aspect, the invention provides a method for the treatment of decreased blood pressure to below 120 mmHg systolic, symptomatic hypotension, cardiogenic shock occurring during an acute coronary syndrome or cardiogenic shock occurring during or after coronary artery bypass surgery or during or after any other cardiac surgery, particularly during or after reperfusion therapy or due to myocarditis, which comprises administering to a patieni in need ulcCth~uof effective amount of a nitric oxide synthase inhibitor.

In one embodiment, the nitric oxide synthase inhibitor, e.g. L-NMMA is administered concomitantly with high doses of cathecolamines such as dopamine and/or dobutamine.

BRIEF DESCRIPTION OF THE DRAWINGS In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: WO 01/00195 Page 8 of 24 WO 01/00195 PCT/IL00/00369 -7- Fig. 1 is shows changes in mean arterial blood pressure (MAP) of patients during L-NMMA administration (mean±SEM); Fig. 2 shows changes in urine output during L-NMMA administration (mean±SEM); Fig. 3 shows changes in Cardiac Index during L-NMMA administration (mean±SEM); and Fig. 4 shows changes in Wedge Pressure during L-NMMA administration (mean+SEM).

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a pharmaceutical composition comprising a nitric oxide synthase inhibitor is provided for the treatment of decreased blood pressure to below 120 mmHg systolic, symptomatic hypotension, cardiogenic shock occurring during an acute coronary syndrome or cardiogenic shock occurring during or after coronary artery bypass surgery or during or after any other cardiac surgery, particularly during or after reperfusion therapy or due to myocarditis.

The pharmaceutical composition may be formulated in any suitable form, for example for oral, cutaneous, or parenteral administration, but preferably will be administered intravenously (IV).

The invention will now be illustrated by the following clinical study carried out to assess the safety and efficacy of L-NMMA in the treatment of cardiogenic shock. Seven consecutive patients with refractory cardiogenic shock who were deemed beyond treatment by two expert cardiologists, were administered L-NMMA 1 mg/kg bolus and 1 mg/kg drip for 5 hours. We observed a steep 31% increase in MAP and a 142% increase in urine output. CI decreased initially by 18% however it returned gradually to baseline. Wedge pressure did not change significantly. The beneficial effect of L-NMMA persisted at 24 hours of hemodynamic follow-up. Of 7 patients with severe cardiogenic shock that were deemed by two expert cardiologists to be beyond treatment and were enrolled in the WO 01/00195 Page 9 of 24 WO 01/00195 PCT/ILOO/00369 -8present study, 6 could be weaned of IABP and 3 are alive at 1 month follow-up.

L-NMMA administration has favorable clinical and hemodynamic effects on patients in cardiogenic shock. It increases mean arterial blood pressure and urine output with marginal effect on heart rate, cardiac output, and pulmonary wedge pressure. No adverse effects could be detected in this cohort. The survival rate of the patients was 43%.

The invention will now be illustrated by the following non-limiting Examples.

0o EXAMPLE

I

Patients: In order to be included, patients with extensive myocardial infarction complicated by refractory cardiogenic shock despite maximal therapy were examined by two expert cardiologists, and deemed beyond any further treatment.

The institutional and National Israeli Ministry of Health Ethical Review Board approved the study protocol. Patients and family gave informed consent.

Seven consecutive patients with recent myocardial infarction (less than 1 week) who had persistent cardiogenic shock despite having undergone percutaneous coronary revascularization and treatment by mechanical ventilation, intra-aortic balloon pump (IABP), and high doses of inotropic cathecolamines were included in this study.

Cardiugenic shock was dfined as peisisteit nlio-augiuente systolic ubiuU pressure below 100 mmHg, accompanied by pulmonary congestion (determined by chest X-ray), cardiac index 2.5 I/minJm2 and wedge pressure 15 mmHg despite the above mentioned treatment.

Excluded were patients with significant tachy- or bradyarrhythmias, significant valvular heart disease or other mechanical complications, secondary heart failure, sepsis (determined by fever >38 degrees), creatinine 200 micromoles/ml, and active ischemia.

Concomitant Treatment: All patients received aspirin, heparin fluids (IV), furosamide drip dopamine (IV) and dobutamine Dopamine and WO 01100195 Page 10 of 24 WO 01/00195 PCT/IL00/00369 -9dobutamine were administered at doses of at least 10 microgram/kg/minute for at least 3 hours prior to enrollment. All patients were mechanically ventilated and subsequently underwent coronary catheterization and insertion of IABP. Maximal percutaneous revascularization was attempted in each patient according to the specific coronary anatomy and clinical assesment. During L-NMMA administration, treatment with fluids, catecholamines, mechanical ventilation and IABP was kept constant.

Treatment Protocol: At least three hours prior to L-NMMA administration, an arterial line and Swan-Ganz catheter were inserted. Throughout treatment, 02 saturation, pulse, blood pressure, urine output, wedge pressure, and cardiac output were all continuously monitored.

L-NMMA (Clinalfa, Cal-biochem) was administered as 1 mg/kg bolus, and then continued as drip of 1 mg/kg/hr for 5 hours. EKG was performed before and after administration of L-NMMA.

Outcome measures: Changes in mean arterial blood pressure, pulse rate, urine output, cardiac output and index, wedge pressure, systemic vascular resistance and pulmonary artery pressure and resistance during L-NMMA administration and at 24 hours of follow-up.

Clinical outcome while on treatment and during 1 month of follow-up.

Adverse events during the treatment period including death, life threatening arrhythmias, deterioration in patients' ciinicai condition, or appearuiace of new ischemia.

Statistical Methods: Changes within a given parameter over the period of the study were analyzed by analysis of variance with repeated measures. P values of 0.05 or less were considered significant.

Results Baseline characteristics of the study population are given in Table I.

Changes in pulse, MAP, pulmonary pressure and resistance, peripheral resistance cardiac output and wedge pressure are presented in Table II.

WO 01/00195 Page 11 of 24 WO 01/00195 PCT/IL0O/00369 Clinical results: Six out of 7 patients could be weaned off mechanical ventilation and intra-aortic balloon pump during or shortly after L-NMMA administration.

Four patients were discharged from the coronary ICU. Three patients were discharged to home. They are alive and well at 1 month of follow-up. The four patients that have died succumbed to multiorgan failure, sepsis, sepsis and hemorrage and cholesterol emboli at 1, 2, 3 and 6 days respectively.

Mean arterial blood pressure (MAP): Five to ten minutes after L-NMMA bolus administration, a steep increase in MAP was observed. MAP increased from 74 mmHg to 97 14 mmHg 31 p 0.0004). This increase in MAP persisted to throughout L-NMMA administration. MAP also remained elevated after 24 hours of follow-up despite discontinuation of L-NMMA. The results are depicted in Fig.

1.

Heart rate: Heart rate decreased by 6 after 10 minutes of treatment and remained largely unchanged during L-NMMA administration and at 24 hours follow-up.

Urine output: Urine output increased from 63 29 cc/hr gradually throughout the study period, reaching 153 75 cc/hr at the fifth hour of treatment 142%, p 0.014). Urine output remained increased at 24 hours of follow-up. The results are depicted in Fig. 2.

Cardiac Index: During the first hour of treatment, while MAP dramatically increased (thereby increasing afterload), the cardiac index decreased from 1.97 0.61 to 1.61 0.56 l/min/m2 However, after three hours of treatment, despite no change in MAP, cardiac index started to increase, reaching 1.75 0.47 l/min/m2 p 0.012) at 5 hours of treatment. At 24 hours of follow up cardiac index has increased to baseline level reaching 1.95+0.44 l/min/m2 (p=ns).

The results are depicted in Fig. 3.

Pulmonary Capillary Wedge Pressure: Similar to cardiac output, the wedge pressure also increased during the first hour of treatment from 20±10 mmHg to 23±10 mmHg However, by the second hour of treatment, wedge pressure decreased to pre-treatment baseline, reaching 20 7 mmHg after 5 hours of WO 01/00195 Page 12 of 24 WO 01/00195 PCT/IL00/00369 -11treatment. Wedge pressure thereafter remained unchanged at 24 hours of follow-up.

The results are depicted in Fig. 4.

Safetyv No patient died during L-NMMA administration. We were unable to detect any clinical or laboratory adverse effects of L-NMMA treatment.

TABLE I: Baseline Characteristics for L-NMMA Parameter: Age: 71.9 Sex: Male: 3 (43%) Female: 4 (57%) Background: Diabetes Mellitus: 5(71%) Hypertension: 4 (57%) Smoking: 2 (29%) Hyperlipidemia: 5(71%) Acute MI: 7 (100%) Wall: Anterior: 6 (86%) Posterior: 1(14%) Peak CK: 3739±732 Catheterization Results f /f 1 Vessel Disease 1 (14%) Revascularization Stent to Left Main 2 (29%) Stent to Proximal LAD 2 (29%) PTCA to Proximal LAD 1 (14%) PTCA to Circumflex 1 (14%) None 1(14%) EF (Echo): 23.5±5.9 TABLE 11: Haemc'dvnamic Parameters Durine L-NMMA Administration.

Variable MAP: Puim. B3P: Pulse: Wedge Cardiac Cardiac SVR PVR Urine mmHg mmHg beats/min. mmHg Output: Index: output Time VIn/m2 0 74±10 33±9 102±11 20±10 3.7±11.2 1.97±0.61I 1653±907 358±233 -'63±29 min. 99±13 39±9 .94±16 22+9 3.3±1.1 1.76±0.56 2512±1147 519±309 P value 0.0007 0.002 0.1 0.12 0.023 0.03 0.0013 0.007 mln. 97±14 41±10 95±19 23±10 3.1±1.1 1.75±0.56 2531±1298 520±310 P value 0.0004. 0.005 0.23 0.07 0.019 0.027 -0.003 0.009 min. 98±14 40±10 99±23 22±10 3.2±1.1 1.68±0.55 2627±1309 547±358 P value 0.0001 0.005 0.6 0.14 0.011 0.014 0.002 0.015 I hour 97±13 40±9 99±23 21±8 3.1±1.1 1.61±0.56 2843±1634 620±547 151±86 P value 0.0003 0.001 0.55 0.27 0.003 0.0001 0.007 0.004 *0.038 2 hours 99±17 40±9 97±24 21±9 3M11O 1.63±0.56 2800±1 647 607±365 122±65 P value 0.0004 0.001 0.4 0.4 0.003 0.004 0.01 0.01 0.036 3 hours 99±15 40±9 98±27 20±7 3.1±1.0 1.65±0.51 2722±1484 629±386 130±83 P value 0.001 0.002 0.49 1.0 0.005 -0.008 0.004 0.01 0.05 4 hours 99±14 40±10 98±28 19±6 3.2±1.0 1.7±0.5 2567±1224 609±371 141±76 P value 0.0008 0.001 0.47 0.7 0.01 0.013 0.001 0.01 0.023 hours 97±15 38±9 100±27 20±7 3,3±0.8 1.75±0.47 2467±1313 549±391 153±75 P value 0.0003 0.001 0.81 0.87 0.016 0.012 0.004 0.03 0.014 24 hour 97±8 38±6 96±22 19+8 3,6±0.9 1.95±0.44 203±457 473±284 175±85 P value 0.004 #i 003 0.34 10.6 10.83 0.89 10.210.12 1# 0.024 WO 01/00195 Pace 14 of 24 WO 01/00195 PCT/IL00/00369 -13- MAP Mean Arterial Blood Pressure.

SVR Systemic Vascular Resistance.

PVR Pulmonary Vascular Resistance.

Statistically significant (P 0.05).

The results of the present study indicate that L-NMMA induces primarily a selective and significant vasoconstriction leading to a steep increase in blood pressure without clinical signs of further cardiac or central nervous system compromise in blood supply and hence no new ischemia. Furthermore, while systemic vascular resistance (SVR, afterload) increases by 75%, only a small and transient effect of treatment on cardiac index has been measured and virtually no change in pulse rate and pulmonary capillary wedge pressure (preload). This implies that myocardial contractility probably increases during L-NMMA administration.

L-NMMA induced brisk diuresis without deterioration in kidney function.

Although pressure induced diuresis caused by a significant increase in mean blood pressure during profound shock could explain this 142 increase in urine output, other possible mechanisms, including a direct effect of L-NMMA on the kidneys was not examined.

Of importance is that L-NMMA administration was not associated with any arrhvthmias and it actually induced a decrease in pulse rate of approximatel 2%.

In the present study, L-NMMA induced a biphasic effect on cardiac output and wedge pressure. During the first 1-2 hours of treatment cardiac output decreased and wedge increased both by approximately 10 20%. This could be explained by: A decrease in pulse rate of 6% that was observed during L-NMMA administration. (therefore, Stroke Volume decreased by only An acute increase in systemic vascular resistance induced by L-NMMA inducing an acute increase in afterload WO 01/00195 Page 15 of 24 WO 01/00195 PCT/ILOO/00369 -14- Activation of cardioinhibitory reflex by the steep increase in blood pressure.

This hypothesis is substantiated by the finding that the decrease in cardiac output was more pronounced in two patients in which the pulse rate has decreased more significantly.

A gradual increase of cardiac output and decrease in wedge pressure was observed after 2-3 hours of treatment. Wedge pressure decreased to baseline measurements after 3 hours and cardiac index increased gradually. At 5 hours during cessation of L-NMVIA treatment cardiac index was still 13% below baseline, however it continued to increase afterwards reaching baseline levels at 24 hours of follow-up. This increase in cardiac output occurred despite persistent elevation of blood pressure and systemic vascular resistance during study period and at 24 hours of follow-up.

At this stage, and probably throughout L-NMMA administration and the following 24 hours, cardiac contractility gradually increases. The modified SVR formula: SVR=(MAP-right atrial pressure) 80 cardiac output, clarifies the dependence of cardiac output and index calculation on SVR. Therefore corrected for the SVR increase throughout the study period the Cardiac Index calculation would actually increase from 1.87 to 2.6 l/min/m2 Also notable is the dramatic increase in the rate pressure product (systolic blood pressure pulse rate) of 19% during L-NMMA administration, while preload conditions (wedge apparent decrease in Cardiac Index, cardiac contractility probably actually increased.

Furthermore, at 24 hours of follow-up, while MAP and SVR are still above baseline cardiac index, pulse rate and pulmonary capillary wedge pressure have returned exactly to baseline levels, implying that myocardial contractility has probably increased.

The increase in myocardial contractility and late increase of cardiac output observed could be explained by either a possible effect of L-NMMVIA on coronary blood flow either directly or secondary to increased coronary perfusion pressure, WO 011001095 WO 01/00195 PCT/ILOO/00369 decreasing ischemia and therefore ameliorating stunning, or a direct effect of L-NMMA on myocardial contractility.

Increased perfusion pressure: The effect of mean or systolic blood pressure in the normal range (systolic blood pressure 120 mmHg) on the outcome of an acute coronary event and especially as an adjunctive treatment to reperfusion therapy was repeatedly suggested. In the consensus II study it was demonstrated that decreased blood pressure in the first 24 hours after an acute myocardial infarction is detrimental. A few studies have demonstrated that normal blood pressure is probably important during thrombolytic treatment. Recently in a study to published in Circulation, Clayes et. al. (12) have shown that in patients older than years systolic blood pressure 120 mmHg after primary PTCR for acute MI was associated with improved resolution of post-MI persistent ST elevations on EKG. Therefore, evidence is accumulating that adequate "normal" blood pressure is one of the most important factors influencing myocardial preservation in patients with an acute coronary event, especially during and after reperfusion.

Direct effect of L-NMMA on myocardial contractility: As stated previously, a positive primary effect of L-NMMA on myocardial contractility was suggested by many recent experimental studies In the present study this possibility is supported by the observation that the decrease in wedge pressure to below pre-treatment levels occurs two hours prior to the increase in cardiac output (figure 2).

Of importance is the persistent effect of L-NMMA at 24 hours of follow up.

It is notable that in a recent pharmacokinetic study of L-NMMA in patients with septic shock it was demonstrated that the tl/2 of L-NMMA is approximately 2 hours. Therefore pharmacokinetic considerations alone cannot explain the effect of L-NMMA after 24 hours, although it is possible that L-NMMA has an unknown active metabolite that exerts some of the late effect.

Therefore, it is believed that the main effect of L-NMMA in the present study is related to its significant selective vasoconstrictive effect. This induces an increased blood pressure, improving microvascular perfusion after reperfusion and Page 16 of 24 WO 011Q0195 Page 17 of 24 Page 17 of 24 WOO01/00195 PCT/ILOO/00369 -16alleviating stunning. As a result, myocardial contractility is improved in a way that the vicious cycle of cardiogenic shock, low blood pressure, decreased microvascular perfusion and increased stunning is broken, enabling some patients to recover.

EXAMPLE I An experiment simnilar to that described above with L-NMUVIA was carried out using instead L-NAME. The results are summarized in the table III: TABLE 1111: Baseline characteristics for b-NAME b-NAME No P Value Treatment Baseline Characteristics______ (i)Unaugrnented MAP (mmHg) 61 69 0.18 Urine/hour (cc) 75 143 0.12 Pulse (beats/min) 85 104 0.21 EF (echo) 26 26 0.9 (a)Primary endpoint______ (i)Death (1 week) 1 /5 4/5 0.05 (81%) (ii)Death (1 Month) 2 /5 4 /5 0.2 (b)Secondary Endpoints Unaugmented MLAP (24 ours)(mmllg) 83 77 0.75 MAP Increase (mmHg) 22 8 0.05 Urine/hour (24 hours)(cc) 245 155 0.26 T JLU T- -I i7 170 1 n 005 a Time on IABP (hours) 38 43 0.86 Time on Mechanical Ventilation 68 123 0.36 (hours) EF at 1 /4 months 1 25/ FC at1/4 months(NYHA class) 2.5/ 3/ The decrease in deaths from 80% to 20% is striking.

WO ''01o WO 01/00195 PCT/ILOO/00369 -17-

REFERENCES

1. Petros A, Lamb G, Leone A, Moncada S, Bennett D, Vallance P.Effects of a nitric oxide synthase inhibitor in humans with septic shock.

Cardiovasc.Res. 1994; 28: 34-39.

2. Krausz, MM, Amstislavsky T, Bitterman, H. The effect of nitric oxide synthase inhibition on hypertonic saline treatment of controlled hemorrhagic shock. Shock. 1997; Dec; 8 422-6.

3. Goodhart DM, Anderson TJ. Role of nitric oxide in coronary arterial vasomotion and the influence of coronary atherosclerosis and its risks. Am.

1o J Cardiol 1998; 82: 1034-9.

4. Parrino P, Laubach VE, Gaughen, JR, Shockey KS, Wattsman, TA, King RC, Tribble CG, Kron IL. Inhibition of inducible nitric oxide synthase after myocardial ischemia increases coronary flow. Annals of Thoracic Surgery. 1998 Sep.; 66 733-9 5. Flesch M, Kilter H, Cremers B, Lenz O, Sudkamp M, Kuhn-Regnier F, Bohm M. Acute effects of nitric oxide and cyclic GMP on human myocardial contractility. JPharmaco Exp Ther. 1997 Jun; 28 1340-9 6. Finkel MS, Oddis CV, Mayer OH, Hattler BG, Simmons RL. Nitric oxide synthase inhibitor alters papillary muscle force-frequency relationship. J Pharmacol Exp Ther 1995 Feb; 272(2); 945-52 7. Naseem SA, Kontos MC, Rao PS, Jesse RL, Hess ML, Kukreja RC.

Sustained inhibition of nitric oxide by NG-nitro-L-arginine improves myocardial function following ischemia/reperfusion in isolated perfused rat heart. JMol Cell Cardiol 1995 Jan; 27(1); 419-26 8. Lepori M, Sartori C, Trueb L, Owlya R, Nicod P, Scherrer U.

Haemodynamic and sympathetic effects of inhibition of nitric oxide synthase by systemic infusion of N(G)-monomethyl-L-arginine into humans are dose dependent. Journal ofHypertension 1998 Apr; 16(4); 519-23 Page 18 of 24 WO 01/00195 Page 19 of 24 WO 01/00195 PCT/ILOO/00369 -18- 9. Hare JM, Keaney JF Jr., Balligand JL, Loscalzo J, Smith TW, Colucci WS.

Role of nitric oxide in parasympathetic modulation of beta-adrenergic myocardial contractility in normal dogs. J Clin Invest 1995 Jan; 95(1); 360-6.

s 10. Hare JM, Givertz MM, Creager MA, Colucci WS. Increased sensitivity to nitric oxide synthase inhibition in patients with heart failure: potentiation of beta-adrenergic inotropic responsiveness. Circulation 1998 Jan; 20; 97(2); 161-6.

11. Depre C, Vanoverschelde J-L, Goudemant J-F, Mottet I, Hue L. Protection against ischemic injury by nonvasoactive concentrations of nitric oxide synthase inhibitors in the perfused rabbit heart. Circulation. 1995; 92: 1911-18.

12. Clayes MJ, Bosmans J, Veenstra L, Jorens P, De Radedt H, Vrints CJ.

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Claims (41)

1. A method of treating cardiogenic shock, comprising administering to a patient in need thereof a therapeutically effective amount of a nitric oxide synthase inhibitor.

2. The method of claim 1 xxherein the natient exhibits one or more svmntnms selected from the group consisting of: hypotension, tachycardia, mental confusion and cold extremities.

3. The method of claim 1, wherein the patient exhibits one or more symptoms selected from the group consisting of: persistent non-augmented systolic blood pressure below 100 mmHg, pulmonary congestion, cardiac index less than 2.5 1/min./m 2 and wedge pressure greater than 15 mmHg.

4. The method of claim 1, wherein the cardiogenic shock is a refractory cardiogenic shock.

The method of claim 1, wherein the cardiogenic shock is during an acute coronary syndrome.

6. The method of claim 1, wherein the cardiogenic shock is during or after a cardiac surgery.

7. The method of claim 6, wherein the cardiac surgery is a coronary artery bypass surgery.

8. The method of claim 1, wherein the cardiogenic shock is during or after 20 reperfusion therapy.

9. The method of claim 1, wherein the nitric oxide synthase inhibitor is a N"- substituted -L-arginine compound.

10. The method of claim 9, wherein the N'-substituted-L-arginine compound is N"- monomethyl -L-arginine ("L-NMMA"). 25

11. The method of claim 9, wherein the N"-substituted-L-arginine compound is an analogue of L-NMMA. Y \Mr NK NO DELETE54237-00A doc

12. The method of claim 11, wherein the analogue of L-NMMA is N'-ethyl-L- arginine, propyl-L-arginine, N'-allyl-L-arginine, or N'-propargl-L-arginine.

13. The method of claim 9, wherein the N'-substituted -L-arginine compound is N'-nitro-L-arginine methyl ester ("L-NAME").

14. The method of claim 1, wherein the nitric oxide synthase inhibitor is administered in a low dose.

The method of claim 14, wherein the nitric oxide synthase inhibitor is administered from about 0.5 to about 1.5 milligrams per kilogram body weight per hour.

16. The method of claim 15, wherein the nitric oxide synthase inhibitor is administered at about 1.0 milligrams per kilogram body weight per hour.

17. The method of claim 1, wherein the nitric oxide synthase inhibitor is administered for about five hours.

18. The method of claim 14, wherein the nitric oxide synthase inhibitor is co- administered with a catecholamine.

19. The method of claim 18, wherein the catecholamine is dopamine, or dobutamine. 2LU. 1 I IhLIUU l0 claill 10, Vwll .1 i111 Ll t'oxide s: .L.J n inibLiti.3 i* c. administered with dopamine and dobutamine.

20

21. The method of claim 1, wherein the nitric oxide synthase inhibitor is administered orally.

22. The method of claim 1, wherein the nitric oxide synthase inhibitor is o i.i administered cutaneously. t23. The method of claim 1, wherein the nitric oxide synthase inhibitor is 25 administered parenterally.

S. Y.VMa WK NO DELETE54237-0A doc 21

24. The method of claim 1, wherein the nitric oxide synthase inhibitor is administered intravenously.

A method of treating cardiogenic shock, comprising administering to a patient in need thereof a therapeutically effective amount of N"-monomethyl -L-arginine NMMA").

26. The method of claim 25, wherein L-NMMA is administered at about milligrams per kilogram body weight per hour.

27. The method of claim 25, wherein L-NMMA is administered for about five hours.

28. The method of claim 25, wherein L-NMMA is co-administered with a catecholamine.

29. The method of claim 25, wherein L-NMMA is administered intravenously.

A method of treating cardiogenic shock, comprising administering to a patient in need thereof a therapeutically effective amount of N'-nitro-L-arginine methyl ester ("L-NAME").

31. The method of claim 30, wherein L-NAME is administered at about milligrams per kilogram body weight per hour.

32. The imetl-od of clai- 30:, wherein i--irAvi Is auministr for C about five hours. OZ III III LIIUU UI tlllll wV IZI Il lll I 1 1.9V iL rI. luIlInnoi .,UIUI L i.

33. The method of claim 30, wherein L-NAME is co-administered with a S 20 catecholamine.

34. The method of claim 30, wherein L-NAME is administered intravenously.

35. A method of treating decreased blood pressure below 120 mmHg systolic during an acute coronary syndrome, comprising administering to a patient in need thereof a therapeutically effective amount of a nitric oxide synthase inhibitor. S 25

36. The method of claim 25, wherein decreased blood pressure below 120 mmHg systolic is during or after reperfusion therapy. 4 5 Y \M rNKJ NO DELETE54237-00A doc 22

37. The method of claim 25, wherein decreased blood pressure below 120 mmHg systolic is due to myocarditis.

38. The method of claim 25, wherein the nitric oxide synthase inhibitor is N'- monomethyl-L-arginine ("L-NMMA").

39. A method of treating symptomatic hypotension during an acute coronary syndrome, comprising administering to a patient in need thereof a therapeutically effective amount of a nitric oxide synthase inhibitor.

The method of claim 39, wherein symptomatic hypotension is during or after reperfusion therapy.

41. The method of claim 39, wherein the nitric oxide synthase inhibitor is N"- monomethyl-L-arginine DATED: 15 April 2005 PHILLIPS ORMONDE FITZPATRICK Attorneys for: Gad Cotter *oo o*~ go• Y:\MarWKI NO DELETE\542370OOA doc