Ranolazine and related piperazines for protecting skeletal muscles

The present invention relates to applications of ranolazine or other piperazine derivative compound of formula I, especially to applications of ranolazine in medicaments for the treatment of tissues which are physically or chemically injured, and more particularly to the treatment of shock conditions.

Ranolazine, ie ± N- (2,6-dimethylphenyl) -4- [2-hydroxy-3- (2-methoxyphenoxy) propyl] -1-piperazineacetamide or 1- [3- (2-methoxyphenoxy) -2-hydroxypropyl] 4 - [(2,6-dimethylphenyl) aminocarbonylmethyl] piperazine, the dihydrochloride salt thereof and the compounds of formula I are described in U.S. Patent No. 4,567,264. Ranolazine is disclosed as a calcium entry blocking compound useful for the treatment of cardiovascular diseases such as myocardial infarction, congestive heart failure, angina pectoris and arrhythmia.

The anti-ischemic effects of ranolazine have been reported in several publications, such as Jain et al., "A PRIMINARY STUDY OF A NEW ANTI-ANGINAL AGENT", Cardiovascular Drugs and Therapy, Vol. 1, No. 3, p. 252 (October 1987). ; Allely and Alps, "THE EFFECTS OF THE NOVEL ANTI-ANGINAL AGENT RANOLAZINE (ID) IN A CANINE MODEL OF TRANSIENT MYOCARDIAL ISCHEMIA", Br. J. Pharmacol., 1988, 93, p. 246; and Ferrandon et al., "PROTECTIVE EFFECTS OF THE NOVEL ANTI-ISCHEMIC AGENT RANOLAZINE (R5-43285) IN PERFUSED RAT HEARTS", Br. J. Pharmacol., 1988, 93, p 247, in which It has been reported to protect the heart from ischemia and / or reperfusion-induced, possibly lethal, biochemical and functional injury. However, protection of the tissue is not achieved by blocking calcium entry and not by a beta-blocking mechanism (Brown et al., Br. J. Pharmacol., 1988, 93, p. 248), and such effective ones Means are also not expected to have a protective effect on the tissue. Further, cardiac depression has been identified as a limiting factor for widespread use of CEBs for the treatment of cardiac-related ischemic diseases (Packer et al., Circn., 75 (V), 56-64, 1987; Barjon et al., J. Med Am. Coll. Cardiol., 9, 622-630, 1987).

One aspect of the present invention relates to the use of an effective amount of a compound of formula I: (formula I)

and the pharmaceutically acceptable ester and acid addition salts thereof, wherein:

R¹, R², R³, R & sup4; and R & sup5; each independently represents hydrogen, lower alkyl, lower alkoxy, cyano, trifluoromethyl, halo, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, N-optionally substituted alkylamido, with the exception that when R 1 is methyl, R & sup4; not methyl; or

R² and R³ together form -OCH₂O-;

R & sup6 ;, R & sup7 ;, R & sup8 ;, R & sup9; and R¹ & sup0; each independently represents hydrogen, lower acyl, aminocarbonylmethyl, cyano, lower alkyl, lower alkoxy, trifluoromethyl, halogen, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, di-lower alkylamino;

R6 and R & sup7; together form -CH = CH-CH = CH-; or

R7 and R & sup8; together form -OCH 2 O-;

Each of R¹¹ and R¹² independently represents hydrogen or lower alkyl; and

W is oxygen or sulfur.

In a preferred embodiment, the invention includes the use of the compound of formula I wherein R¹ and R & sup5; in which R², R³, R &, R¹¹ and R¹² stand for hydrogen and in particular in which W is oxygen. Most preferred is the use of ranolazine, ie, wherein R & sup6; is methoxy and R & sup7 ;, R & sup8 ;, R & sup9; and R¹ & sup0; stand for hydrogen.

The present invention contemplates a use for the manufacture of medicaments for the treatment of shock conditions (including cardiogenic shock), which method comprises administering to a subject experiencing a shock an effective amount of a compound of Formula I, preferably Ranolazine ,

Another aspect of the invention involves an application for co-administration of a compound of formula I together with another pharmaceutically active agent, such as thrombolytic agents [especially TPA (tissue plasminogen activator) or streptokinase] or angina pectoris (as disclosed in U.S. Pat for example, beta-blockers, including propranolol and timolol).

Definitions and general parameters

The following definitions are given to illustrate and define the meaning and scope of the various terms used to describe the invention.

As used herein, the term "treatment" or "treating" means any treatment of a disease in a mammal, including:

(i) preventing the disease, that is, preventing the development of the clinical symptoms of the disease;

(ii) inhibiting the disease, that is, arresting the development of clinical symptoms; and or

(iii) relieving the disease, that is, causing the decline in clinical symptoms.

As used herein, the term "qs" means adding an amount sufficient to achieve a specified function, e.g. B. adjust a solution to the desired volume (ie 100%).

As used herein, the term "effective amount" means a dosage sufficient to provide a treatment for the disease condition to be treated. This varies depending on the patient, the disease and the treatment to be performed.

Preparation of Ranolazine

Ranolazine and the piperazine compounds of Formula I can be prepared, for example, as described in U.S. Patent No. 4,567,264.

Availability, testing and administration

Surprisingly, it has been found that ranolazine is effective in methods of treatment that are unrelated to its originally established calcium entry-blocking mechanism and cardioselective indications. Of particular interest is the finding that ranolazine has been found to protect tissue from ischemia (enhancing the efficiency of cellular use of oxygen) at doses that do not produce cardiodepressant effects (see Allely and Alps, supra and Ferrandon et al., Supra). ,

General availability

The piperazine compounds of formula I, especially ranolazine and the pharmaceutically acceptable salts thereof (preferably the dihydrochloride) are useful for the treatment of tissues which are physically or chemically injured. Such a treatment may, for example, be against cardioplegia or against hypoxic reperfusion injury to the heart muscle or to skeletal muscle or brain tissue. The compounds of formula I, especially ranolazine and its salts, are also useful by administration to the graft donor, transplant recipient or by perfusion of the tissues to be transplanted for the preservation (eg prevention of degradation) of donor grafts used in grafts. Tissues, especially useful for kidney transplants, skin grafts, heart grafts, lung grafts, corneal grafts and liver grafts.

exam

The protection of the myocardium from ischemic damage is experimentally demonstrated by inducing an infarct in a suitable experimental animal (eg a baboon) and subsequently increasing the enzyme concentrations (especially creatine kinase "CK" (especially creatine kinase "CK" triggered by the injury) ( also known as creatine phosphokinase, "CPK") and lactate dehydrogenase "LDH"). It is generally accepted that the levels of these enzymes are increased following myocardial injury (Galen et al., JAMA, 232, 145-147, 1975) and that such enzyme concentrations can be obtained by an experimental model under conditions that include the from Alps et al. (Arzneim. Forsch. Drug Res., 33, (1), 6, 868-876, 1983). The actual measurement of enzyme concentrations is determined by the method of Galen (Med. Times, 105 2, 89-99, 1977). The compounds of formula I, as illustrated by ranolazine, effectively reduce the concentrations of CK and LDH enzymes, as measured by this assay.

Protection against myocardial ischemia can also be assessed by the effectiveness of preventing ischemia-induced increase in the number of alpha-1 adrenoceptors in the myocardium. It is known that the alpha-1 adrenoceptor population increases in the myocardial ischemia (Heathers et al., Circulation Research, 61, 735-746, 1987). It has also been shown that alpha-1 adrenoceptor antagonists have beneficial effects during ischemia in animal models (Wilbur et al., J. Cardiovascular Pharmacol., 10, 96-106, 1987). Thus, agents that prevent the ischemia-induced increase in the density of alpha-1 adrenoceptors are beneficial during myocardial ischemia. The ability of compounds of formula I, as illustrated by ranolazine, to inhibit the ischemia-induced increase in alpha-1 adrenoceptors in the myocardium is determined in rat left ventricle using one of Allely and Brown (Br. J. Pharmacol. 705, 1988) and the method of Williams et al. (Cardiovascular Pharmacology, 3, 522, 1981) for measuring the density of alpha-1 adrenoceptors. A detailed description is given in Example 4.

The protection of skeletal muscles from damage resulting, for example, from major surgical practices, was experimentally evaluated in the same model used to assess its protective effects in the myocardial area. For this purpose, skeletal muscle specific isoenzymes CPK? and LDH & sub5; as indications for a damaged muscle according to the method of Galen (Med. Times, 105 (2), 89-99, 1977).

The protection of the myocardium from the deleterious effects of ischemia induced by open heart surgical procedures and other cardiac surgical procedures, including cardioplegia, is assessed by a modified Langendorff method which involves measuring the pH of the coronary outflow and the Includes lactate concentration. These tracers are recognized as indicative of tissue damage induced by a marked reduction in nutrient delivery to the heart (Armiger et al., Biochem Med., 29, 265-267, 1983; Gilst et al., Ar chives of Pharmacol., Suppl., 330, p. 161, 1985). A detailed description is given in Example 2.

The utility of compounds of formula I, as illustrated by ranolazine, in organ grafts is achieved by administering the test compound to pigs prior to nephrectomy and / or adding the compound to the fluid used to rinse and store the organ. and by assessing the functionality of transplanted kidneys for a period of 14 days. The improvement in kidney function in the treated animals is assessed by measuring the glomerular filtration rate as well as the highest concentrations of creatinine and urea in the serum. Glomerular filtration is a well-established indicator of renal function (see, for example, Mudge and Weiner in The Pharmacological Basis of Therapeutics, Goodman and Gilman, 879, 7. Ed., 1985) and is generally assessed by measuring inulin and / or creatinine clearance (Textbook of Medicine, 1088-93, 14th Ed., 1975 - Beeson and McDermott, Eds.).

Cerebral ischemia is the result of either a generalized or localized prolonged reduction in blood flow to the brain. Such a reduction in blood flow can result from a variety of pathological conditions, including cerebral venous inflammation and thrombosis, heart disease, changes in the blood (coagulation, viscosity, anemia) or cardiac surgery practices. One of the signs of damage caused by cerebral ischemia is the increase in the plasma isoenzyme creatine phosphokinase 1 (CPK 1) (Rossi et al., Am J. Cardiol., 58 (13), 1236-1241, 1986). The inhibition of the peripheral appearance of CPK & sub1; is an indication of reduced brain ischemia damage. This is demonstrated by administration of a test compound prior to ligation of the coronary artery in the baboon as a bolus iv injection followed by infusion during the period of reperfusion as described by Alps et al. (Arzneim. Forsch. Drug Res., 33, (1), 6, 868-876, 1983).

administration

The administration of ranolazine in pure form or in a suitable pharmaceutical composition can be carried out by any of the generally accepted modes of administration of agents which serve similar uses. Thus, the administration may be, for example, oral, nasal, parenteral or topical, including by perfusion. The administration may be in the form of solid or semi-solid dosage forms, lyophilized powder or liquid dosage forms such as tablets, suppositories, capsules, powders, solutions, suspensions, emulsions, creams, lotions, aerosols, ointments or the like, preferably in unit dosage forms which are suitable for easy administration of accurate dosages. The compositions include a conventional pharmaceutical carrier or excipient and an effective amount of ranolazine or a pharmaceutically acceptable salt thereof, and may additionally include other medical agents, pharmaceutical agents, carriers, adjuvants, etc. Continuous release formulations or slow release formulations for maintaining high or constant dosage ranges are also useful in the present invention. Ranolazine may also be coadministered with other effective agents such as thrombolytic agents [especially TPA (tissue plasminogen activator) or streptokinase] or anti-anginal agents (such as beta-blockers, including propranolol or timolol).

The preferred method of administration is parenteral, except in cases where the patient must be pre-treated prior to surgery or if the patient must be on therapy for acute episodes of ischemia (in which case oral administration of the composition may be preferred).

Depending on the intended mode of administration, the pharmaceutically acceptable compositions will generally contain from about 1% to about 99% by weight of the pharmaceutically active compound of this invention and from 99% to 1% by weight of suitable pharmaceutical excipients. Preferably, the composition consists of from about 5 to 75% by weight of a pharmaceutically active compound, the balance consisting of suitable pharmaceutical excipients.

For liquid and semi-solid formulations, about 5 mg / ml is preferred as the maximum concentration for the active ingredient.

Oral administration entails the use of a convenient daily dosage regimen which can be adjusted for the degree of discomfort. For such oral administration, a pharmaceutically acceptable non-toxic composition is formed by the incorporation of any of the normally used excipients, such as mannitol, lactose, starch, pharmaceutical grade magnesium carbonate, and the like. Such compositions take the form of solutions, suspensions, tablets, capsules, powders, sustained or slow release formulations, and the like.

Preferably, the oral compositions take the form of a capsule or tablet, and thus the composition, together with the active ingredient, contains a diluent such as lactose, sucrose, dicalcium phosphate and the like; an explosive such as starch or derivatives thereof; a lubricant such as magnesium stearate and the like; and a binder such as starch, gum arabic, polyvinylpyrrolidone, gelatin, cellulose and derivatives thereof and the like.

The active compounds may be prepared using, for example, from about 0.5% to about 50% of the active ingredient contained in a polyethylene glycol (PEG) carrier [e.g. PEG 1000 (96%) and PEG 4000 (4%)] or semisynthetic glycerides (Witepsol ™, Suppocire ™) is formulated as a suppository.

Another preferred mode of administration is parenteral. Liquid, pharmaceutically administrable compositions may be prepared, for example, by dissolving, dispersing, etc., an active compound (about 0.5% to about 20%) as described above and optional pharmaceutical adjuvants in a carrier, such as water, saline, aqueous dextrose , Glycerin, ethanol and the like, to form a solution or suspension.

For the preservation of tissues awaiting transplantation, a perfusion solution is preferred. Such solutions include an active compound in a carrier such as Eurocollins solution (Fresenius, AG, Bad Homburg, vdH, Germany), University of Wisconsin Fluid (Kalayoglu, M. et al., The Lancet, 1988 i, 617), phosphate buffered sucrose (see, e.g., Example 7E) and hyperosmolar citrate (Ross et al., Transplantation, 1976, 498-501).

If desired, the pharmaceutical composition to be administered may also contain minor amounts of non-toxic excipients, such as wetting or emulsifying agents, pH buffering agents, and the like, such as sodium acetate, sorbitan monolaurate, triethanolamine oleate, etc.

Actual methods of preparing such dosage forms are known or apparent to those skilled in the art; See, for example, Remington's Pharmaceutical Sciences, 16th ed. (Mack Publishing Company, Easton, Pennsylvania, 1980). The composition to be administered will in any event contain an amount of the active compound (s) in a pharmaceutically effective amount to alleviate the particular condition being treated when administered in accordance with the teachings of this invention.

Example 5 describes oral and parenteral formulations containing ranolazine. Such formulations should not be construed as limiting the invention. Specifically, parenteral formulations may be administered as dilutions with perfusion fluids, dialysis fluids and / or fluids used for irrigation and storage of organs. It is also intended that the invention encompasses the possibility of combining ranolazine with other pharmaceutical agents than co-regulation or by simultaneous dissolution in fluids.

dosage

In general, ranolazine is administered in a therapeutically effective amount, ie, a dosage sufficient to effect treatment. The amount of active compound administered will of course depend on the patient being treated, the weight of the patient, the severity of the disease, the route of administration and the discretion of the prescribing physician. In the absence of sufficient time to weigh the foregoing factors in detail, e.g. B. in emergency situations, however, effective iv dosages are in the range of about 0.05 to about 5 mg / kg for bolus injection, followed by infusion ranging from about 0.3 to about 30 mg / kg / hour lies. Preferably, the iv bolus dosage is in the range of about 0.1 to about 2.5 mg / kg and the infusion dosage of about 1.5 to about 15 mg / kg / hour. For a person with an average weight of 70 kg is the iv Bolus in the range of about 3.5 to about 350 mg, or preferably from about 15 to about 105 mg. In other situations, for a human with an average weight of 70 kg, the oral dosage will range from about 35 to about 1400 mg per day, preferably from about 70 to about 700 mg / day. For administration by a perfusion fluid, a concentration of about 0.001 to about 5 g per liter, preferably about 0.005 to about 2.5 g per liter, and most preferably about 0.005 to about 0.1 g per liter is used; Perfusion can continue from the removal of the tissue from the donor to its use for transplantation.

Examples

The following formulations and examples are provided to enable those skilled in the art to more clearly understand and practice the present invention. They should not be considered as limiting the scope of the invention, but only as an illustration and illustration thereof.

example 1

Protection against heart ischemia

This is an adaptation of the model described by Alps et al. (Arzneim. Forsch. Drug Res., 33, (1), 6, 868-876, 1983).

Eight male baboons were anesthetized and then randomly assigned to one of two groups:

Group A (control group)

Four animals were subjected to a 30-minute occlusion of the left anterior descending coronary artery (LAD) followed by a reperfusion period of 5.5 hours. Venous plasma samples taken before thoracotomy, prior to LAD ligation and every hour during the reperfusion period were analyzed for CPK₂ and LDH₁ isozyme levels.

Group B (treated group)

As in group A, except that the animals started an initial dose of ranolazine (500 μg / kg) intravenously 10 minutes prior to LAD ligation, followed by a continuous infusion of 50 μg / kg / min for a period of 6 hours at the time of LAD ligation.

Results

Plasma CPK₂ isoenzyme levels remained below the detection limit until the first hour after infarction. LDH1 plasma levels were identical to pre-surgery and pre-ligation (pre-infarct period) times. Results, as given in Table I, are expressed in international units of isoenzyme per liter of plasma. Table I

As shown above, ranolazine strongly inhibited the release of CPK? and LDH 1, such result indicating effective protection of the myocardial tissue from adverse effects of ischemia.

Example 2

Myocardial protection during cardioplegia

This method has been described by Ferrandon et al., Br. J. Pharmacol., 1988, 93, p. 247.

Male Sprague-Dawley rats were anesthetized with pentobarbitone sodium (50 mg / kg, ip). After injection of heparin (200 units iv), the thorax was opened. The heart with a pendant portion of the aorta was removed and then placed in ice-cold Krebs solution (118mM NaCl, 4.55mM KCl, 1.2mM KH 2 SO 4, 1.2mM MgSO 4, 11.0mM glucose, 20.0 mM NaHCO3, 1.35 mM CaCl2, pH 7.4). The heart was gently scanned to expel the blood. Hearts were then treated with the above solution, heated to 37 ° C, and gassed with 95% O 2. and 5% CO 2, retrograde via the aorta (Langendorff model) using a peristaltic pump set to deliver 14 ml / min. A microelectrode was inserted into the ventricular muscle wall and a reference electrode was placed in contact with the perfusion fluid 3 cm above the heart. The two electrodes were connected to a pH meter.

Hearts were perfused at 14 ml / min for a period of 15 minutes to obtain a stable baseline ventricular pH. The aortic flow was then reduced to 1 ml / min for 15 minutes by lowering the pump speed. The flow was then readjusted to the initial rate for 15 minutes. Values ​​for coronary flow and ventricular pH were measured at 5 minute intervals. After restoration of the initial flow rate, measurements were made at 30 seconds, 1 minute, and 5 minutes. Samples of coronary outflow were collected and stored on ice. Infusions of ranolazine (1 μM) were started 10 minutes before the flow rate was reduced and continued for the remainder of the experiment. At the end of the experiment, the atria were removed and the hearts were dried at 75 ° C for 2 days.

The biochemical determination of lactate released into the coronary outflow was done using a spectrophotometric method. The amount of lactate contained in the samples was obtained by reference to a calibration curve. Lactate release from the heart mass was calculated using the following formula:

[Lactate] (μmol / ml) · coronary flow (ml / min) / dry weight of the heart (g)

The results are shown in Tables 2 and 3. Table 2

Ranolazine thus inhibits ischemia-induced pH drop by about 50%. Table 3

* Values ​​are expressed as micromol of lactate released per minute into the coronary outflow of 1 g of dried heart.

The compounds of the invention thus clearly reduced the effects of low flow perfusion.

Example 3

Protection against brain ischemia

The incidence of isoenzymes in peripheral venous blood was determined according to the experimental conditions as in Example 1, except that the plasma samples were assayed for CPK & sub1; were examined. The results are shown in Table 4. Table 4

The results are expressed in International Units per liter of plasma and clearly demonstrate the protective role of ranolazine in cerebral ischemia.

Example 4

Protection against myocardial ischemia

Male Sprague-Dawley rats were anesthetized with pentobarbitone and mechanically ventilated with room air. Left-sided thoracotomy was then performed, and the left anterior descending coronary artery (LAD) was blocked for a period of 30 minutes. In control animals, a ligature was positioned but not tightened.

Compounds (500 μg / kg ranolazine, saline vehicle) were administered ip for 3 days (twice daily) plus 15 minutes before constipation.

At the end of the ischemic period, the ischemic zone of the left ventricle was excised and for the density of alpha-1 adrenoceptors by the method described by Williams et al. (Cardiovascular Pharmacology, 3, 522, 1981). The apparent density of alpha-1 adrenoceptors was calculated at 0.1 nM [3 H] -prazosin and the results expressed as femtomole receptors per mg protein as shown in Table 5. These results indicate that ranolazine inhibits the ischemia-induced increase in the density of alpha-1 adrenoceptors in the left ventricle in rats and is therefore useful for preventing tissue damage resulting from myocardial ischemia. Table 5

Example 5

formulations

The following example illustrates the preparation of representative pharmaceutical formulations containing a compound of Formula I as illustrated by ranolazine. AIV FORMULATION (low concentration) BIV FORMULATION (high concentration)

To prepare the iv formulations, ranolazine and dextrose monohydrate are dissolved in water (70 percent of the desired final volume), then sodium hydroxide (10 N solution) is added with stirring until the pH is 4, and the volume is made up to 100 mL with water , The medium is filtered through a 0.2 μm membrane filter and packaged under sterile conditions in ampoules or vials. Alternatively, the medium may be filtered under non-sterile conditions, packaged in ampoules, and then sterilized by autoclaving.

C. FILM COATED TABLET FORMULATION

Ingredients Parts by weight

Ranolazine HCl (A) 80.0

microcrystalline cellulose (B) 16.5

Polyvinylpyrrolidone (C) 1.0

Sodium Cross Carmellosis (D) 2.0

Magnesium Stearate (E) 0.5

(A), (B) and half of (D) are mixed, and then (C) and water are added to allow wet granulation. (E) and the remainder of (D) are finally added. After thorough mixing, the granulated mixture is dried, formed into tablets containing up to 250 mg of the active compound, and the tablets are film-coated using White Opadry ™, following appropriate procedures.

D. FORMULATION WITH TAXED RELEASE

Ingredients Parts by weight

Ranolazine BASE (A) 90

microcrystalline cellulose (B) 10

The two above ingredients are mixed dry, then water is added to form a wet mass suitable for extrusion and then spheronization (0.5 to 1.4 mm). Microspheres are coated with suitable release controlling polymers and then placed in hard capsules containing up to 250 mg of the active ingredient per unit.

E. PERFUSION FLUID

Ingredients Parts by weight

Ranolazine 20 mg

Phosphate-buffered sucrose:

Sucrose 48.0 g

Sodium dihydrogen phosphate 4.59 g

Sodium monohydrogen phosphate 6.53 g

Water for Injection (USP) qs to 1000 ml

The components are dissolved in a portion of the water for injection, and once solution is obtained, the remaining volume is supplemented with water for injection.