FR2970178A1 - PROMOTERS FOR SPECIFIC LIVER LEVEL DELIVERY AND BETTER TOLERANCE - Google Patents

Abstract

The invention relates to a prodrug according to the general formula (I) X - R wherein X represents a therapeutic agent whose site of action is the liver and R represents a saturated or unsaturated fatty acid, linear or branched, comprising from 3 to 12 carbon atoms, optionally substituted by one or more hydroxyl groups, halogen atom, and cyclic hydrocarbon comprising from 3 to 6 carbon atoms, or a pharmaceutically acceptable salt or stereoisomer thereof. It also relates to a pharmaceutical composition containing at least one prodrug according to the invention combined with a suitable vehicle, more particularly for oral administration. Use of a prodrug of the invention or a pharmaceutical composition in the preparation of a medicament for the treatment or prevention of various diseases.

Description

PRODRUGS FOR SPECIFIC LIVER LEVEL DELIVERY AND BETTER TOLERANCE.

The invention relates to novel prodrugs, their preparation and use. The prodrugs of the invention can be used to deliver therapeutic agents to the liver with high tissue specificity, including statins.

A prodrug or prodrug is a pharmacological substance, or drug that is administered in an inactive form. Once administered, the prodrug is metabolized in vivo to an active metabolite. A prodrug is generally used to optimize absorption, distribution, metabolism and excretion. It is generally designed to improve the oral bioavailability, or even to increase the selectivity of the product for the intended target.

The therapeutic agents of interest in the context of this invention may be any agent whose site of action is the liver, for example anti-cancer, antiparasitic, lipid-lowering or anti-diabetic drugs, or else therapeutic agents used in the metabolic diseases. By action site at the level of the liver according to the invention is meant that the therapeutic molecule has its activity in the liver. Anti-cancer agents used to treat liver cancer include, for example, 5-fluorouracil derivatives (5-FU), Mitomycins, Sorafenib. Examples of oral hypoglycemic agents acting on the liver include biguanide derivatives (metformin, Glucophage ®) or alpha-glucosidase inhibitors. Among the lipid-lowering agents acting at the level of the liver, there may be mentioned, for example, fibrates or statures. In the present invention, statins are more particularly described as a therapeutic agent. This should not, however, reduce the scope of the prodrugs described in the present invention. Statins are a class of lipid-lowering drugs used to lower cholesterol levels in people with cardiovascular risk. Statins exert their lipid-lowering effects through the inhibition, at the level of the liver, of the key enzyme of cholesterol synthesis, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG CoA reductase). This effect is dose-dependent.

The known statins are in particular fluvastatin ((6E) -7- [3- (4-fluorophenyl) -1- (propan-2-yl) -1H-indol-2-yl] -3,5-dihydroxyhept-6 acid. -enoic), pravastatin or (3R, 5R) -3,5 = dihydroxy-7 - ((1R, 2S, 6S, 8R, 8aR) -6-hydroxy-2-methyl-8 - {[2S] acid) 2-methylbutanoyl] oxy} -1,2,6,7,8,8a-hexahydronaphthalen-1-yl) heptanoic acid, ator-vastatin or (3R, 5R) -7- [2- (4-fluorophenyl) ) -3-phenyl-4- (phenyl carbamoyl) -5- (propan-2-yl) -1H-pyrrol-1-yl] -3,5-dihydroxyheptanoic acid, rosuvastatin or acid 7- {4- (4- Fluorophenyl) -6-isopropyl-2- [methyl (methylsulfonyl) amino] pyrimidin-5-yl} -3,5-dihydroxyhept-6-enoic acid, cerivastatin or 7- (4- (4-fluorophenyl) -5- (methoxymethyl) -2,6-bis (1-methylethyl) -3-pyridinyl) -3,5-dihydroxy- (S- (R *, S * - (E))) 6-heptanoic acid, and pitivastatin or acid (3R, 5S, 6E) -7- [2-Cyclopropyl-4- (4-fluorophenyl) quinolin-3-yl] -3,5-dihydroxyhept-6-enoic. It is recognized that statins are effective in decreasing cholesterol levels in the blood and in reducing the risk of occurrence or recurrence of diseases resulting from narrowing or occlusion of arteries. Statins are rapidly absorbed intestinal tract, then enter the liver by passive diffusion or through liver transporters. They exert their hypolipidemic effect and are then rapidly metabolized and excreted via the bile. For this reason, the bioavailability of statins is reduced, it is dependent dose up to a certain level and at high doses, when there is saturation of hepatic metabolism, circulating levels of statins can increase considerably causing many adverse effects.

Although the benefit / risk of statins is very favorable especially at low and intermediate doses, more and more cases of intolerance are reported in clinical practice in patients treated at higher doses. These side effects include muscle and liver effects. The main undesirable effects observed affect the musculoskeletal system and are myalgia, cramps, reduction of muscle strength or fatigue, increase in creatine phosphokines (CPK). These effects may in the most severe cases lead to rhabdomyolysis. These risks are increased in vulnerable patients such as the elderly, patients with renal insufficiency, subjects with genetic modification of hepatic transporters or subjects with concomitant treatments interfering with the hepatic metabolism of statins, for example fibrates, Verapamil® , and in whom the systemic exposure is increased. With respect to hepatic effects, pharmacovigilance studies of statins showed significant elevations (3 x ULN) of liver transaminases reported with an incidence of 1% at low doses and 2-3% at high doses (American Journal Cardiol. 2006 Apr 17; 97 (8A): 77C-81C. David E. Cohen et al. These elevations are dose dependent and common to all statins. The majority of increases occur in the first 3 months of treatment and require monitoring. As a result, there is a need to develop new drugs or prodrugs, in particular statins, capable of eliminating or at least reducing the side effects observed during treatments, while preserving a specific activity related to the therapeutic agent, an effective or even improved activity. WO 2009/054682 discloses prodrugs of atvastatin which are said to solve certain problems related to the administration of atvastatin. The compounds described are different from those disclosed in the present invention.

The inventors have discovered novel prodrugs of therapeutic agents which surprisingly allow to have a good therapeutic activity in the liver while decreasing the side effects. In particular, they have discovered novel statin prodrugs that surprisingly effectively inhibit cholesterol synthesis in the liver while decreasing muscle and liver toxicity.

Thus, the subject of the invention is a prodrug according to the general formula (1) in which: X represents a therapeutic agent whose site of action is the liver,

R represents a saturated or unsaturated fatty acid, linear or branched, comprising from 3 to 12 carbon atoms, optionally substituted with one or more hydroxyl groups, halogen atom, and cyclic hydrocarbon comprising from 3 to 6 carbon atoms, or a pharmaceutically acceptable salt or stereoisomer thereof.

By therapeutic agent whose site of action is the liver is meant, for example, anti-cancer, anti-parasitic, hypolipidemic, anti-diabetic, or therapeutic agents used in metabolic diseases. By statin is meant any known or newly developed statin, which can react with a fatty acid as defined below, to form a prodrug according to the invention: The chemical reaction between the therapeutic agent whose site of action is the liver and the radical R is carried out so that once hydrolysed in the liver, the pro-drug releases an active therapeutic agent. When the chemical reaction is carried out between a statin and an R radical, it is carried out by esterification on the acid function common to all the statins. The statins are in particular those mentioned above and they specifically inhibit HMG-CoA reductase. The term "fatty acid" means any carboxylic acid with a non-cyclic aliphatic chain. They comprise from 3 to 12 carbon atoms and are either saturated, that is to say that all the carbon atoms are saturated with hydrogen (without double bond), or unsaturated, ie they contain one or more carbon-carbon double bonds, they can be conjugated (double bond separated by a single bond) or non-conjugated (double bond separated by 2 single bonds). The fatty acids may be linear, that is to say straight chain, or branched, that is to say comprising one or more short carbon radicals, especially methyl and ethyl radicals. Cyclic hydrocarbon means hydrocarbons whose carbon chain is cyclic. They include cycloalkanes, cycloalkenes and cycloalkynes. There may be mentioned in particular cyclopropane, cyclobutene and cyclohexane.

The prodrugs according to the invention make it possible to obtain a better pharmaceutical efficacy of the hydrolysed therapeutic agents and / or a better tolerance of the latter. In a preferred embodiment according to the invention, the therapeutic agent X is chosen from anti-cancer, anti-parasitic, lipid-lowering, anti-diabetic, or therapeutic agents used in metabolic diseases. In a more preferred embodiment according to the invention, the therapeutic agent is a statin chosen from fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin. Statin prodrugs preferentially inhibit hepatic cholesterol synthesis (improved efficacy) while eliminating or at least reducing adverse effects (better tolerance). They also make it possible to reduce or even eliminate liver toxicity. These prodrugs thus provide a considerable advantage in terms of public health, especially for vulnerable patients treated with high doses of statins. Thus, the prodrugs of statin according to the invention make it possible to increase the dose to be administered up to double that dose compared to the high doses used at present. For example, rosuvastatin is known to be administered at a high dose of 40 mg. The prodrugs of the invention can thus be administered at a high dose of up to about 80 mg rosuvastat equivalent and with a better tolerance for the treated subject. An example is atorvastatin administered at 80 mg in high doses. The prodrugs according to the invention can thus be administered at a high dose of up to about 160 mg equivalent of atorvastatin (ie for example 184 mg of ProATV as described in Example 4 below), and this with a better tolerance for the subject being treated. The prodrug of statin according to the invention has a radical R preferably representing a linear or branched, saturated or unsaturated fatty acid comprising from 3 to 10 carbon atoms, preferably a linear or branched saturated fatty acid comprising from 3 to 8 carbon atoms. carbon. In another preferred embodiment according to the invention, the statin prodrug is: the butanoic, pentanoic, hexanoic or heptanoic ester of fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin, the ester pentaenoic C3 and C4 of fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin. In a very preferred embodiment according to the invention, the prodrug of statin is pentaenoic ester C3 and C4 of atorvastatin and the butanoic ester of atorvaeatine. Another object according to the invention is a pharmaceutical composition containing at least one prodrug according to the invention, associated with a suitable vehicle. The pharmaceutical composition according to the invention is preferably suitable for oral administration. When the prodrug according to the invention is administered to humans orally, it may be in the form of a solid formulation, such as, powder, granules, tablets, or capsules, for example, or in the form of a liquid formulation preferentially contained in a capsule, or a syrup. When it is in the form of a tablet (or not), any suitable pharmaceutical vehicle can be used for the formulation of such solid compositions, for example microcrystalline cellulose, lactose monohydrate, crosscarmellose, polysorbate 80 hydroxypropyl cellulose, magnesium stearate, starch, lactose, glucose, rice, flour and chalk, and film-coating agents. The compound may also be in the form of a capsule to be ingested, consisting for example of gelatin, containing the compound in solution, suspension or emulsion, or in the form of a syrup, a solution, an emulsion or a suspension. Suitable pharmaceutical vehicles are, for example, dispersing, disintegrating, stabilizing, antioxidant agents (including omega-3 such as eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) or omega-6), adsorbents, agents for improving intestinal absorption, solubilizing agents, SEDDS "self Emulsifying Drug Delivery System", which can be added, for syrups, flavoring or coloring agents. Sustained release formulations, for example tablets containing an enteric coating, are also contemplated. All the ingredients and oral forms used will aim at improving the bioefficacy of the prodrugs according to the invention. Another object according to the invention is the use of a prodrug according to the invention, or a pharmaceutical composition according to the invention, in the preparation of a medicament for the treatment or prevention of various diseases for which the Action site of the drug is located at the level of the liver. A preferred embodiment according to the invention is the use of a prodrug or a pharmaceutical composition according to the invention in the preparation of a medicament for the treatment or prevention of various diseases which are due to a specific excessive cholesterol in the blood, including the risk of occurrence or recurrence of myocardial infarction, angina pectoris, arterial occlusive disease of the lower limbs and cerebrovascular accident. This embodiment is more particularly applicable to prodrugs or pharmaceutical compositions of statins. Thus, another preferred embodiment according to the invention is the use of a prodrug or a pharmaceutical composition in the preparation of a medicament for treating heart failure, chronic renal failure, colon cancer and lung, reduction of fracture frequencies in osteoporosis, reduction of progression of diabetes, deep vein thrombosis or phlebitis, dementia, Alhzeimer's disease, multiple sclerosis and infections.

The process for the preparation of the prodrug according to the invention is generally carried out in one step, by chemical reaction of a therapeutic agent X with a radical R. This chemical reaction makes it possible to block the link which will subsequently be hydrolysed at the level of the liver. For example, the process for preparing the statin prodrug according to the invention is carried out by esterification between a molecule of statin and a hydroxy acid derivative of fatty acid. The prodrug obtained may be an amorphous form or a crystalline form with several polymorphs, and will preferably be the most thermodynamically stable crystalline form. It can then be used in its acid or salt form. The reaction is presented below

X-000H + R-OH -> X-000R. The following examples illustrate the invention without limiting it.

Example 1: Preparation of a 92 mg oral tablet of Pro-ATV (equivalent to 80 mg of atorvastatin) comprising atorvastatin butanoic ester in its most stable crystalline form (hereinafter referred to as ProATV). Pro-ATV 92 mg Microcrystalline cellulose 126.5 mg. Lactose monohydrate 35 mg 10 Crosscarmellose 10 mg Polysorbate 80 1.5 mg Hydroxypropyl Cellulose 2.0 mg Magnesium Stearate 3.0 mg 270 mg film-coated tablet (hypromellose, titanium dioxide, talc, macrogol 6000, isopropyl alcohol, and dichloromethane).

EXAMPLE 2 Preparation of an Oral Suspension Comprising Pentaenoic Ester of Atorvastatin with a C3 and Cl Double Bond The formulation is prepared extemporaneously. This is a 5 mg / ml suspension of this compound in 0.5% methylcellulose.

Example 3: Comparative study of hepatic uptake of fluvastatin and atorvastatin versus their respective prodrugs. Study carried out on preparation of human hepatocytes and on HepG2 cells. The capture reaction was initiated by adding the radiolabeled products to the cell suspension. After 2 minutes of incubation, the reaction is stopped, and the samples prepared to determine the amount of products captured in the liver by liquid scintillation measurement. In both cases, radioactivity levels showed greater hepatic uptake with pro-drugs compared to the reference agents.

Example 4: Oral administration to man of the butanoic ester prodrug of atorvastatin.

This single-center, randomized, open-label, 2-period, 2-sequence, crossover study assesses the safety, pharmacokinetic (PK) and pharmacodynamic (PD) profile of this ProATV entity at a dose of 92 mg compared to atorvastatin (ATV, Tahor®) at the 80 mg equimolar dose. 12 healthy male volunteers with LDL-Cholesterol (LDL-C) values of between 130-180 mg / dL and 18-55 years of age were selected for this study according to the following criteria:

The selected male healthy volunteers and eligible subjects were randomized within 10 days of the selection visit. The subjects were randomized to: Sequence 1: Period 1: ProATV (92 mg) - Period 2: ATV (80 mg) - Sequence 2: Period 1: ATV (80 mg) - Period 2: ProATV (92 mg) The ProATV and ATV were administered from D1 to D14 for period 1 and from D21 to D35 for period 2. The subjects were admitted to the clinical center the day before the first administration (OJ for period 1 and D20 for period 2). They remained there for 48 h after the first administration of each period and left the site on D3 for period 1 and D 23 for period 2. A wash period of 7 days with placebo was observed between the 2 periods. The objectives of the study are: Primary: To evaluate the general tolerance of oral ProATV for 14 days to volunteer male subjects with high LDL-C. Secondary: Evaluate the PK profile of atorvastatin and its major metabolites after 2 weeks of treatment with proATV or atorvastatin. To evaluate the PD effects of proATV by measuring biomarkers such as: total cholesterol, LDL-C, Apo B. Evaluate the relative bioavailability of atorvastatin after administration of ProATV or atorvastatin at equimolar doses.

The products administered are: ProATV (92 mg): in the form of a 92 mg ProATV tablet corresponding to that described in Example 1 above.

Placebo: 1 oral tablet of identical appearance to the tested product. The products are administered on an empty stomach with a glass of water (approximately 150 ml). Neither food nor water is administered for a period of at least 2 hours after administration of the products.

The evaluation criteria are: For tolerance: adverse reactions (AEs) / serious adverse effects "(EISs), physical examination, vital signs (blood pressure, heart rate), weight and body mass index, electrocardiogram (ECG), hematology (Hb, Ht, NFS, platelets), biochemistry (sodium, potassium, chloride, bicarbonate, calcium, albumin, AST, ALT, alkaline phosphatase, total bilirubin, CPK, creatinine, glucose, urea) For the PK of ATV and its metabolites (2-OH, 4-OH, and lactone): the concentration (Cmax, CSS,., Css,., n), the time to reach the peak (t) concentration, area under the curve (AUC) and total clearance (LC / F) and half-life (Tin). These parameters were evaluated on day 14 and day 35. For PD: total cholesterol levels, LDL-C, Apo B, and HDL-C These parameters were measured on D1, D14, D21 and D35.

Determination of number of subjects: The number of subjects of 6 per sequence was evaluated in order to obtain first information looking at the tolerance, the PK and the PD of the proATV compared to the ATV.

Procedure: Samples for PK analysis: Pre-dose at D14 and D35 and at 0.25, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8, 10, 12, 16, 24 , 48 and 72 hours. The samples (10 mL) are collected in chilled tubes and heparins with esterase inhibitors. Plasma is obtained by centrifugation (10 min at 1800 g and at 4 ° C) within 30 minutes after collection. Plasma samples are divided into 2 aliquots of 1 ml and 4 aliquots of 0.5 ml and frozen immediately at -80 ° C. Samples for analysis of PD: A D1 and D21 (before the first dose), D14 and D35 at the end of each period. The procedure is shown in Figure 1. The results of the study are as follows: Disposition, Demographics, Characteristics: All randomized subjects received and completed their treatment according to the protocol. All have a high LDL-C at baseline.

Tolerance No subject interrupted the study. No problem of tolerance is observed. No biological or clinical parameters are reported as clinically significant adverse events.

Pharmacokinetics: After administration of the 2 products, the absorption rate was fast (faster for proATV compared to ATV). The most important metabolite is, in descending order: 2-OH-ATV> ATV> 4-OH ATV.

The relative bioavailability of ATV and its metabolites after repeated administration of ProATV 92 mg to healthy high cholesterol subjects is 50% compared to the reference product, ATV 80 mg (equimolar dose). The half-life of ATV is between 10 and 15 h for the 2 products administered. Pharmacodynamics: The mean decrease in LDL-C, total cholesterol and ApoB following a 14-day repeated dose is similar for ProATV and the reference product, ATV: -60%, -50% and -50%, respectively. A 10% increase in HDL-C is also observed with both products.

PK / PD Data from PK / PD show that the effects of both products on LDL-C and total cholesterol levels are identical despite a 50% lower plasma exposure for ProATV (Area under the atorvastatin and its metabolites) compared with atorvastatin.

No correlation between the plasma levels of atorvastatin or its hydroxymetabolites and the decrease of total cholesterol or LDL-C is found.

Conclusions: Repeated administration of ProATV 92 mg for two weeks on an empty stomach is well tolerated.

ProATV shows similar efficacy on lipid profile (LDL-C and total cholesterol) compared to atorvastatin, associated with a 50% decrease in systemic exposure. This decrease in exposure is commonly associated with a decrease in adverse effects such as: myalgia, CPK elevation, rhabdomyolysis.

ProATV is therefore of substantial interest for the 10% of patients treated at high doses of statins with muscle-related adverse effects as well as for at-risk populations such as the elderly, subjects on concomitant treatment interfering with the systemic exposure of the patients. statins or for certain subjects with a phenotype associated with a reduction in hepatic transporter activity leading to an increase in plasma exposure to the product and its metabolites. Similarly, the effects observed on liver enzymes are marked hands with proATV compared to equimolar dose ATV. Hepatic deleterious effects are generally dose-dependent and the best observed tolerance for proATV is a substantial benefit in patients requiring high dose therapy.

Claims (4)

REVENDICATIONS1. A prodrug according to the general formula (I) X - R (I) wherein X represents a therapeutic agent whose site of action is the liver and X is selected from anti-cancer, anti-parasitic, lipid-lowering, anti-cancer drugs. diabetics, or therapeutic agents used in metabolic diseases, R represents a saturated or unsaturated fatty acid, linear or branched, comprising from 3 to 12 carbon atoms, optionally substituted by one or more hydroxyl group, halogen atom, and cyclic hydrocarbon having 3 to 6 carbon atoms, or a pharmaceutically acceptable salt or stereoisomer thereof. 2. The prodrug as claimed in claim 1, wherein the therapeutic agent is a statin chosen from fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin. 3. Statin prodrug according to claim 2, characterized in that R represents a linear or branched, saturated or unsaturated fatty acid comprising from 3 to 10 carbon atoms, preferably a saturated, linear or branched fatty acid comprising from 3 to 8 carbon atoms. carbon atoms. 30 4. A statin prodrug according to claim 3, characterized in that it is the butanoic, pentanoic, hexanoic or heptanoic ester of fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin. 25. Statin prodrug according to claim 3, characterized in that it is the C3 and C4 pentaenoic ester of fluvastatin, pravastatin, atorvastatin, rosuvastatin, cerivastatin and pitivastatin. 6. Statin prodrug according to claim 5, characterized in that it is pentaenoic ester C3 and C4 of atorvastatin. 7. A statin prodrug according to claim 4, characterized in that it is the butanoic ester of atorvastatin. 8. Pharmaceutical composition characterized in that it contains at least one prodrug according to any one of claims 1 to 7, associated with a suitable vehicle. 9. The pharmaceutical composition according to claim 8, characterized in that it is suitable for oral administration. Use of a prodrug according to claims 1 to 7 or a pharmaceutical composition according to claims 8 and 9 in the preparation of a medicament for the treatment or prevention of various diseases for which the site of action of the medicament 20 is located in the liver. Use of a prodrug or pharmaceutical composition according to claim 9 in the preparation of a medicament for the treatment or prevention of various diseases which are due to excessive blood cholesterol, including the risk the occurrence or recurrence of myocardial infarction, angina pectoris, peripheral arterial occlusive disease, and cerebrovascular accident. 12. Use of a prodrug or pharmaceutical composition according to claim 11 in the preparation of a medicament for treating heart failure, chronic renal failure, colon and lung cancers, reduction of fractures during osteoporosis, reduced progression of diabetes, deep vein thromboses or phlebitis, dementia, Alhzeimer's disease, multiple sclerosis and infections.