WO1997042953A1

WO1997042953A1 - Use of brequinar and derivatives in chronic rejection of allografts and xenotransplantation

Info

Publication number: WO1997042953A1
Application number: PCT/EP1997/002401
Authority: WO
Inventors: Hendrik Schuurman
Original assignee: Ciba Geigy AG; Novartis AG
Current assignee: Novartis AG
Priority date: 1996-05-10
Filing date: 1997-05-09
Publication date: 1997-11-20
Anticipated expiration: 1998-11-10
Also published as: AU2896097A

Abstract

Analogues of brequinar, e.g., of formula (I), are found to be useful in the treatment and prevention of allograft chronic rejection and xenograft hyperacute, acute or chronic rejection.

Description

Use of Brequinar and Derivatives in Chronic Reiection of Alloαrafts and Xenotransplantation

The invention relates to a new use for quinohne derivatives in free form or in pharmaceuti¬ cally acceptable salt form in the manufacture of a medicament for the treatment and/or pre¬ vention of chronic rejection of an allograft; or hyper-acute, acute or chronic rejection of a xenograft, in a mammalian recipient thereof, utilizing quinohne derivatives and salts thereof

2-Carbocyclιc and 2-heterocyclιc quinohne carboxylic acids are described in US 5,523,408, incorporated by reference, as potent inhibitors of dihydroorotate dehydrogenase, the fourth enzyme in the de novo pyrimidine nucleotide biosynthesis pathway, and therefore have a unique mechanism of action (inhibition of dihydroorotate dehydrogenase) which is distinct from other available immunosuppressive agents. They are useful in the treatment and/or prevention of organ transplantation rejection, graft versus host disease, autoimmune diseases, and chronic inflammatory diseases in a mammal.

Phenylquinoline carboxylic acids and their derivatives are described as tumor inhibiting agents in US 4,680,299, incorporated by reference. US 4,968,701 and US 5,204,329, in¬ corporated by reference, disclose that the compounds of US 4,680,299 have immunomodu- lating and anti-inflammatory activity, and therefore, alone or with other immunosuppressive agents, would be useful in the treatment of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and myastenia gravis; as well as organ transplantation rejection in general and graft vs. host disease; and also as anti-in- fiammatory agents in the treatment of chronic inflammatory diseases such as rheumatoid arthritis, psoriasis, and inflammatory bowel disease.

3-Phenyl-5,6-dιhydrobenz[c]acrιdιne-7-carboxylιc acid compounds and derivatives thereof are described as tumor inhibiting agents in US 4,918,077 and US 5,002,954, incorporated by reference. US 5,135,934 and US 5,190,753 describe the use of these compounds as immunosuppressive or immunomodulatory agents for the treatment and/or prevention of organ transplantation rejection in general, graft versus host disease, autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, myasthenia gravis and systemic lupus ery¬ thematosus, psoriasis and other chronic inflammatory diseases. Organ transplants of liver, kidney, lung and heart are now regularly performed as treatment for endstage organ disease. Because of the current shortage of human donors for transplantable allografts, attention has focused on the possibility of using xenografts (transplants between species) in transplantation. One of the major obstacles in transplanting successfully xenografts in humans is immunological, especially antibody mediated hyperacute or acute rejection.

A further obstacle in allo- and xenotransplantation is the chronic rejection, and thus organ transplantation is not yet a clinically viable solution to irreversible organ disease.

Chronic rejection, which manifests as progressive and irreversible graft dysfunction, is the leading cause of organ transplant loss, in some cases already after the first postoperative year. The clinical problem of chronic rejection is clear from transplantation survival times, about half of kidney allografts are lost within 5 years after transplantation , and a similar value is observed in patients with heart allografts.

Chronic rejection is considered as a multifactoπal process in which not only the immune reaction towards the graft but also the response of the blood vessel walls in the grafted organ to injury ("response-to-injury" reaction) plays a role. The variant of chronic rejection with the worst prognosis is an arteriosclerosis-like alteration, also called transplant vascu- lopathy, graft vessel disease, graft arteriosclerosis, transplant coronary disease, etc. This vascular lesion is characterized by migration and proliferation of smooth muscle cells, probably under influence of growth factors that are amongst others synthesized by endo¬ thelial cells. This leads to intimal proliferation and thickening, smooth muscle cell hyper¬ trophy repair, and finally to gradual luminal obliteration (vascular remodelling). It appears to progress also through repetitive endothehal injury induced amongst others by host antibody or antigen-antibody complexes; also so-called non-immunological factors like hypertension, hyperlipidemia, hypercholesterolemia etc. play a role.

Chronic rejection appears to be inexorable and uncontrollable because there is no known effective treatment or prevention modality Thus, there continues to exist a need for a treat¬ ment effective in preventing, controlling or reversing manifestations of chronic graft vessel diseases It has now been found that quinohne derivatives of formula I as defined hereinafter are shown, unlike conventional immunosuppressants, e.g., Cyclosporin A or FK-506, to suppress antibody-mediated responses, as are characteristic in xenograft rejection, and are also indicated to prevent or combat chronic rejection in a transplanted organ.

Suitable quinohne derivatives are compounds of the formula

wherein

R¹, R², R³ and R⁴ are independently H, halogen, CF₃₎ Cι-C₄alkyl, S-CH₃ or S(0)_m-CrC₅alkyl, at least two of R¹, R², R³ and R⁴ being H; R⁵ is CO(0)H or CO(O)C₂-C₄alkylene-NR⁸R⁹; R⁶ is H or Cι-C₃alkyl or when R⁷ is A¹, A² or A³, also -CN, -NR⁸R⁹, -OR¹⁰, -SR¹⁰, -NO₂, -CF₃,

-OCF₃ or -SCF₃;

R⁷ is a radical of formula A¹, A², A³ or B

(A¹) (A²) (A³) (B) wherein

R¹¹ is H, halogen, unsubstituted or halogen substituted d-C₃alkyl, -NR⁸R⁹, -OC_rC₃alkyl or

-SC,-C₃alkyl; R¹² is aryl or heteroaryl which are optionally substituted by one or more substituents selected from H, halogen, unsubstituted or halogen substituted Cι-C₃alkyl, -NR⁸R⁹, -OR¹⁰ and -SR¹⁰; R¹³ and R¹⁴ independently are H or Cι-C₃alkyl;

R¹⁵ is CrCι₂alkyl, C₆cycloalkyl, C₄heterocycloalkenyl, aryl, aralkyl, O-aryl, O-aralkyl, S(0)_m-aryl or S(0)_m-aralkyl, wherein m is 0, 1 or 2 and aryl and aralkyl are optionally substi- tuted by one or more substituents selected from H, halogen, unsubstituted or halogen sub¬ stituted C_rC₅alkyl, C^Csalkoxy, N0₂ and OH; R¹⁶ is H, halogen, unsubstituted or halogen substituted Cι-C₅alkyl, CrC₅alkoxy, N0₂ and

OH; X is -N(R¹⁰)-, -O-, -S- or -CH=CH-; Y is -N- or -C(R¹⁰)-; and

Z is -C(R⁸)(R⁹)-, wherein R^8' and R⁹ independently are H or Cι-C₃alkyl; or R⁶ and R⁷ together form a radical of formula C

wherein

R¹⁷ and R¹⁸ are H or taken together are S;

R^β and R⁹ are independently H or Cι-C₃alkyl; or R⁸ and R⁹ together form a C₄- or C₅alkylene which is optionally interrupted by -NH-, -N(CH₃)- or -0-; R¹⁰ is H or Cι-C₃alkyl; m is 0, 1 or 2; with the following provisos for compounds wherein R⁷ is a radical of formula B

(a) R¹, R² and R³ cannot all be H;

(b) R¹⁵ cannot be C₆cycloalkyl when R⁵ is CO(0)(CH₂)2-N(CH₃)2, R³ is CH₂CH₃ or R² is Cl;

(c) when R¹⁵ is C₆cycloalkyl and R⁶ is H R³ must be Cl or F, but R³ and R¹ cannot both be Cl; and

(d) when R³ is CH₃, then R² cannot be Cl; including their pharmaceutically acceptable salts and prodrug forms.

Halogen is to be understood as meaning a representative of the group consisting of fluorine, chlorine, bromine and iodine. Fluorine, chlorine and bromine are preferred, especially fluorine and chlorine.

Alkyl is intended to include both branched and straight chain saturated aliphatic hydro¬ carbon groups having the specified number of carbon atoms. Cycioalkyl may contain preferably 5 to 8 and particularly preferably 5 or 6 ring carbon atoms.

For the purposes of the present invention, aryl or heteroaryl is a five- or six-membered ring or a bicycle consisting of two condensed six- or five-membered rings or one six-membered and one five-membered ring, and in the case of heteroaryl one or more C atoms may be re¬ placed, independently of one another, by an atom selected from the group consisting of oxygen, nitrogen and sulfur. Examples are derived from benzene, naphthalene, indene, furan, pyrrole, pyrazole, imidazole, isoxazole, oxazole, furazan, thiadiazole, thiophene, thiazole, oxadiazole, triazole, indole, indazole, purine, benzimidazole, benzoxazole, benzo- thiazole, pyran, pyridine, pyridazine, triazine, pyrimidine, pyrazine, isoquinoline, cinnoline, phthalazine, quinohne, quinazoline, pterdine, benzotriazine or quinoxaline. Aryl is preferably naphthyl and phenyl. Phenyl is particularly preferred. Heteroaryl is preferably furanyl, pyri- dinyl and pyrimidinyl.

As used herein, "pharmaceutically acceptable salts and prodrugs" refer to derivatives of the disclosed compounds that are modified by making acid or base salts, or by modifying functional groups present in the compounds in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to the parent compounds. Examples include, but are not limited to, mineral or organic acid salts of basic residues such as amines; and alkali or organic salts of acidic residues such as carboxylic acids; acetate, formate and benzoate derivatives of alcohols and amines; and the like. Salts of carboxylic acid residues may include, but are not limited to, sodium, potassium, diethanolamine, N- methyl-D-glucamine, procaine, lysine, choline or tris-(hydroxymethyl)aminomethane.

Pharmaceutically acceptable salts of the compounds of this invention can be prepared by reacting the free acid or base forms of these compounds with a stoichiometric amount of the appropriate base or acid in water or in an organic solvent, or in a mixture of the two; generally nonaqueous media like ether, ethyl acetate, ethanol, isopropanol, or acetonitrile are preferred. Lists of suitable salts are found in Remington's Pharmaceutical Sciences, 17th ed., Mack Publising Company, Easton, PA 1985, p. 1418, the disclosure of which is hereby incoφorated by reference. In a preferred embodiment the compounds which can be used according to the invention have the formula la, lb or Ic

wherein

R¹, R², R³, R⁴, R⁵, R⁶, R¹¹, R¹², R¹³, R¹⁴, X, Y and Z have the above meanings; including their pharmaceutically acceptable salts and prodrug forms.

More preferred are compounds of the formula la, lb and Ic wherein R¹, R² and R⁴ are H; R³ is F or CF₃; R⁵ is CO(0)H; R⁶ is H or CH₃; R¹¹ is H; R¹² is phenyl which is optionally substi¬ tuted by one or two substituents selected from H, CH₃, OCH₃, F and CF₃; R¹³ and R¹⁴ are H; X is -N(R¹⁰)- or -CH=CH-; Y is -N- or -C(R¹⁰)-; Z is -C(R⁸)(R^9')-, wherein R^8' and R^9' independently are H or d-C₃alkyl; R¹⁰ is H or CrC₃alkyl; including their pharmaceutically acceptable salts and prodrug forms.

More preferred compounds according to the invention are compounds of formula la, lb or Ic wherein R¹² is phenyl, 2-methylphenyl, 2-fluorophenyl, 2-methoxyphenyl, 3-methoxyphenyl or 3-trιf luoromethylphenyl.

Specifically preferred compounds useful in the present invention are compounds selected from the following:

6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-2-[4-(2-fiuorophenyl)-1-ιndolιnyl]-3-methylquinolιne-4-carboxylic acid, sodium salt; 6-fluoro-[4-(2-methoxyphenyl)-1-indolinyl]-3-methylquinoiine-4-carboxylic acid, sodium salt; 6-fluoro-3-methyl-2-[4-(2-methylphenyl)-1-indolinyl]-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-[4-(3-methoxyphenyl)-1-indolinyl]-3-methylquinoiine-4-carboxylic acid, sodium salt; 6-fluoro-3-methyl-2-[4-(3-trifluoromethylphenyl)-1-indolinyl]-quinoline-4-carboxylic acid, sodium salt;

6-fluoro-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-2-[4-(2-methylphenyl)-1-indolinyl]-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-2-[4-(3-trifluoromethylphenyl)-1-indolinyl]-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-3-methyl-2-(4-phenyl-1-indolyl)-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, diethanolamine salt; 6-fluoro-3-methyl-2-(4-phenyl-1 -indolinyl)-quinoline-4-carboxylic acid, N-methyl-D-glucamine salt;

6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, procaine salt; 6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, lysine salt; 6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid, choline salt; 6-fluoro-3-methyl-2-(4-phenyl-1 -indolinyl)-quinoiine-4-carboxylic acid, tris-(hydroxymethyl)- aminomethane salt;

6-fluoro-3-methyl-2-(5-phenyl-1 -naphthyl)-quinoline-4-carboxylic acid, sodium salt; 6-fluoro-3-methyl-2-(7-phenyl-1 -methyl-3-indolyl)-quinoline-4-carboxylic acid, sodium salt; 3-methyl-2-(7-phenyl-1 -methyl-3-indolyl)-6-trifluoromethylquinoline-4-carboxylic acid, sodium salt; and 6-fluoro-3-methyl-2-(6-fluoro-4-phenyl-1-benzimidazolyl)-quinoline-4-carboxylic acid.

Certain of the compounds of formula la, lb and Ic may contain one or more asymmetric car¬ bon atoms and may be isolated in optically active or racemic forms. All chiral, diastereome- ric, and racemic forms are included in the present invention. It is well known in the art how to prepare optically active forms, such as by resolution of racemic forms or by synthesis, trom optically active starting materials. All chiral, diastereomeric, racemic forms and all geo¬ metric isomeric forms of a structure are intended, unless the specific stereochemistry or iso¬ mer form is specifically indicated.

In another preferred embodiment of the present invention the compounds which can be used according to the invention have the formula II

wherein

R¹, R², R³, R⁴, R⁵, R⁶, R¹⁵ and R¹⁶ have the above meanings; including their pharmaceutically acceptable salts and prodrug forms; with the following provisos

(a) R\ R² and R³ cannot all be H;

(b) R¹⁵ cannot be C₆cycloalkyl when R⁵ is CO(0)(CH₂)₂-N(CH₃)_2l R³ is CH₂CH₃ or R² is Cl;

(d) when R³ is CH₃, then R² cannot be Cl.

More preferred are those compounds of the formula II wherein R¹, R², R³ and R⁴ are inde¬ pendently H, F, Cl, Br, I, CH₃, CF₃, SCH₃ or CH₂CH₃, at least two of R¹, R², R³ and R⁴ being H; R⁵ is CO(O)H or CO(O)C₂-C₄alkylene-NR⁸R⁹; R⁶ is H, C,-C₂alkyl or Od-C₃alkyl; R⁸ and R⁹ are independently H or Cι-C₃alkyl; R¹⁵ is d-C^alkyl, C₆cycloalkyl, aryl, aralkyl, O-aryl, O-aralkyl, S(0)_m-aryl or S(O)_m-aralkyl, wherein m is 0, 1 or 2 and aryl and aralkyl are optionally substituted by one or more substituents selected from H, F, Cl, Br, d-C₅alkyl, CF₃, OCH₃, N0₂ and OH; R¹⁶ is H, F, Cl, Br, d-C₅alkyl, CF₃, OCH₃, N0₂ or OH; including their pharmaceutically acceptable salts and prodrug forms.

Most preferred are those compounds of the formula II wherein R¹ and R² are independently H or F, Cl, Br or I; R³ and R⁴ are independently H, F, Cl, Br, I, CH₃ or CF₃, at least two of R¹, R², R³ and R⁴ being H; R⁵ is CO(0)H, CO(0)K, CO(0)Na or CO(0)C₂-C₄alkylene-NR⁸R⁹; R⁶ is H or d-C₂alkyl; R⁸ and R⁹ are independently d-C₃alkyl; R¹⁵ is cyclohexyl, phenyl, phenyl substituted with one halogen, Ci-C₅alkyl, CF₃, phenoxy, phenoxy substituted with one halo¬ gen or Cι-C₅alkyl; and R¹⁶ is H.

Particularly preferred are compounds of the formula lla

wherein R³ and R⁴ are independently H, halogen or CF₃, provided that both R³ and R⁴ are not H; R⁵ is CO(O)H, CO(O)K, CO(O)Na or CO(O)C₂-C₄alkylene-NR⁸R⁹; R⁶ is H or d- C₂alkyl; R⁸ and R⁹ are independently Cι-C₃alkyl; R¹⁵ is cyclohexyl, phenyl, phenyl independently substituted with one or two substituents selected from halogen, d-C₃alkyl and CF₃, phenoxy, phenoxy substituted with one or two substituents selected from halogen, Cι-C₅alkyl and CF₃, provided that when R¹⁵ is phenyl or phenoxy, and R⁴ is H, then R³ cannot be Br; and that when R¹⁵ is cyclohexyl and R⁶ is H, R³ must be Cl or F.

Specifically preferred compounds useful in this invention are:

2-(1 ,1 '-biphenyl-4-yl)-5-chloro-3-methyl-4-quinoline carboxylic acid, sodium or potassium salt;

2-(1 ,1 '-biphenyl-4-yl)-5-fluoro-3-methyl-4-quinoline carboxylic acid, sodium or potassium salt;

6-fluoro-3-methyl-2-(4-phenoxyphenyl)-4-quinoline carboxylic acid, sodium or potassium salt;

2-(4'-bromo-1 ,1'-biphenyl-4-yl)-6-fluoro-3-methyl-4-quinoline carboxylic acid, sodium or potassium salt;

2-(2'-fluoro-1 ,1 '-biphenyl-4-yl)-6-fluoro-3-methyl-4-quinoline carboxylic acid, sodium or potassium salt.

Further compounds useful in the method of the invention are listed below in Table 1.

Table 1 :

In still another preferred embodiment of the present invention the compounds which can be used according to the invention are of the formula III

wherein

R³, R⁴, R⁵, R¹⁷ and R¹⁸ have the above meanings; including their pharmaceutically acceptable salts and prodrug forms.

More preferred are compounds of formula III wherein R³ and R⁴ are independently H, F, Cl, Br, I, CH₃, CH₂CH₃, CF₃ or SfOJ_m-d-Csalkyl; R⁵ is CO(O)H or CO(O)C₂-C₄alkylene-NR⁸R⁹; R⁸ and R⁹ are independently H or d-C₃alkyl; R¹⁷ and R¹⁸ are H or taken together are S; including their pharmaceutically acceptable salts and prodrug forms, in one embodiment, with the proviso that when R⁵ is CO(O)Na then R³ is not F.

Most preferred compounds useful in the method of the present invention are those com¬ pounds of formula III wherein (a) R⁵ is CO(0)H or CO(0)Na; and/or (b) R⁴ is H or Cl; and/or (c) R³ is H, F, Cl or CF₃.

Particularly preferred compounds useful in the method of the present invention are those compounds of formula III wherein (a) R⁴ is H; and/or (b) R³ is H, F or CF₃.

Specifically preferred compounds useful in the method of the present invention are:

5,6-dihydro-3-phenylbenz[c]acridine-7-carboxylic acid, or a sodium salt;

5,6-dihydro-9-fluoro-3-phenylbenz[c]acridine-7-carboxylic acid, or a sodium salt;

6,7-dihydro-3-fluoro-[1]benzothieno[2',3':4,5]-benz[1 ,2-[c]acridine-5-carboxylic acid, or a sodium salt;

6,7-dihydro-[1]-benzothieno[2',3':4,5]-benz-[1 ,2-c]acridine-5-carboxylic acid, or a sodium salt; and

5,6-dihydro-3-phenyl-9-trifluoromethyl-benz[c]acridine-7-carboxylic acid, sodium salt. Most suitable compounds are

(i.e. 5,6-dihydro-3-phenyl-9-trifluoromethyl-benz[c]acrιdine-7-carboxylic acid) in free or pharmaceutically acceptable salt form (e.g., sodium salt form); or

(i.e. 6-fluoro-2-(2'-fluoro-1 ,1'-biphenyl-4-yl)-3-methyl-4-quιnoline carboxylic acid), or phar¬ maceutically acceptable salt form thereof (e.g., sodium salt form); or

(i.e. 6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quιnohne-4-carboxyhc acid) or its pharmaceu¬ tically acceptable salt forms (e.g. sodium salt form); or

(i e. 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolyl)-quιnolιne-4-carboxylιc acid) or a pharmaceuti¬ cally acceptable salt form (e.g. sodium salt form).

The compounds of formula la, lb and Ic useful in this invention are described in and pre¬ pared by methods set forth in US 5,523,408, the disclosure, synthesis, and synthetic examples of which are hereby incorporated by reference.

The compounds of formula II useful in this invention are described in and prepared by methods set forth in US 4,680,299, the disclosure, synthesis and synthesis examples are hereby incorporated by reference. Further compounds are set forth in US 4,968,701 incor¬ porated by reference herein

The compounds of formula III useful in this invention are described in and prepared by me¬ thods set forth in US 4,918,077, US 5,002,954, US 5,135,934 and US 5,190,753, the dis¬ closure, synthesis, and synthetic examples of which are hereby incorporated by reference.

According to the particular findings of the invention the compounds of formula I and their pharmaceutically acceptable salts and prodrug form are useful for the treatment and/or prevention of chronic rejection of an organ or tissue allograft; or hyper-acute, acute or chronic rejection of an organ or tissue xenograft, in a mammalian recipient thereof

The invention thus provides:

1. A method of treating or preventing (i) chronic rejection of an allograft, or (n) hyperacute, acute, or chronic rejection of a xenograft, comprising administering a therapeutically or pro- phylactically effective amount of a compound of formula I (in particular, 5,6-dιhydro- 3-phenyl-9-trιfluoromethyl-benz[c]acπdιne-7-carboxyhc acid, 6-fluoro-2-(2'-fluoro-1 ,1'-bι- phenyl-4-yl)-3-methyl-4-quιnohne carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolιnyl)- quιnolιne-4-carboxylιc acid or 6-fluoro-3-methyl-2-(4-phenyl-1 -ιndolyl)-quιnolιne-4-carboxylιc acid or a pharmaceutically acceptable salt form thereof) (e.g., sodium salt form) to a subject in need thereof.

2. A pharmaceutical composition comprising a pharmaceutically effective amount of a com¬ pound of formula I (in particular, 5,6-dιhydro-3-phenyl-9-tπfluoromethyl-benz[c]acrιdιne- 7-carboxylιc acid, 6-fluoro-2-(2'-fluoro-1 ,1 '-bιphenyl-4-yl)-3-methyl-4-quιnolιne carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1-ιndoiιnyl)-quιnolιne-4-carboxylιc acid or 6-fluoro- 3-methyl-2-(4-phenyl-1 -ιndolyl)-quιnohne-4-carboxylιc acid in free acid or pharmaceutically acceptable salt form) (e.g., sodium salt form), together with a pharmaceutically acceptable diluent or carrier, for use in the treatment or prevention of (i) chronic rejection of an allograft, or (2) hyperacute, acute, or chronic rejection of a xenograft.

3. Use of a compound of formula I (in particular, 5,6-dιhydro-3-phenyl-9-tnfluoromethyl- benz[c]acπdιne-7-carboxylιc acid, 6-fluoro-2-(2'-fluoro-1 ,1 '-bιphenyl-4-yl)-3-methyl-4-quιno- line carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1-ιndoiιnyl)-quιnolιne-4-carboxyhc acid or 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolyl)-quιnohne-4-carboxyhc acid in free acid or pharma¬ ceutically acceptable salt form) (e.g., sodium salt form), in the manufacture of a medicament for treating or preventing (i) chronic rejection of an allograft; or (n) hyperacute, acute or chronic rejection of a xenograft

4 Use of a compound of formula I (in particular, 5,6-dιhydro-3-phenyl-9-tπfluoromethyl- benz[c]acπdιne-7-carboxylιc acid, 6-fluoro-2-(2'-fluoro-1 ,1 '-bιphenyl-4-yl)-3-methyl-4-quιno- iine carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolιnyl)-quιnolιne-4-carboxylιc acid or 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolyl)-quιnolιne-4-carboxylιc acid in free acid or pharma¬ ceutically acceptable salt form) (e.g., sodium salt form), for treating or preventing chronic rejection of an allograft of hyperacute, acute or chronic rejection of a xenograft.

Organs or tissues may be transplanted from a donor to a recipient of the same species (allograft) or different species (xenograft). Among such transplanted organs or tissues and given illustratively are heart, lung, combined heart-lung, trachea, liver, kidney, spleen, pancreatic (complete or partial, e.g. Langerhans islets), skin, bowel, or cornea or a combination of any of the foregoing.

Dosages of compounds of formula I required in practicing the present invention will vary de¬ pending on the compound of formula I employed, the host, the mode of administration, and the nature and severity of the condition to be treated. The compounds of formula I may be administered by conventional means, preferably orally, e.g., in the form of tablets of capsu¬ les, or parentally, e.g., in the form of injectable solutions or suspensions. In general, satis¬ factory results are obtained on oral administration at dosages of from about 0.1 to about 100 mg/kg/day, preferably from 1 to 20 mg/kg/day, e.g., 3 to 10 mg/kg/day, administered in 1 , 2, 3, or 4 doses/day. Suitable daily dosages for oral administration to larger mammals, e.g., humans, are generally about 50 to 1500 mg, preferably in the order of from 200 to 800 mg.

The compounds can also be administered topically as an ointment, cream, gel, spray, in¬ haler, solution, aerosol, liposome, patch, etc.

Dosage forms used to administer the active ingredient usually contain suitable carriers, di¬ luents, preservatives, or other excipients, as described in Remington's Pharmaceutical Sciences, Mack Publishing Comapny, a standard reference text in the field.

The compounds of formula I for use in the treatment or prevention of xenograft rejection or chronic rejection may be administered alone or in combination with one or more other anti- inflammatory or immunosuppressive agents, e.g., as described above in connection with allograft rejection, for example in combination with cyclosporin A and analogs thereof, FK- 506 and analogs thereof, rapamycin and analogs thereof, mycophenolic acid, mycophenol- ate mofetil, mizoribine, 15-deoxyspergualine, leflunomide, steroids, cyclophosphamide, aza- thioprene (AZA), or anti-lymphocyte antibodies or immunotoxins such as monoclonal anti¬ bodies to leukocyte receptors, e.g. MHC, CD2, CD3, CD4, or CD25; especially in combina¬ tion with a T-cell suppressant, e.g., cyclosporin A or FK-506. Such combination therapy is further comprised within the scope of the invention, e.g., a method according to 1 above fur¬ ther comprising administration concomitantly or in sequence of a therapeutically or synergi- stically effective amount of such a second immunosuppressive or anti-inflammatory agent.

Utility of the compounds of formula I in treating diseases and conditions as hereinabove specified may be demonstrated in animal tests, for example in accordance with the methods hereinafter described.

A. In vivo heart xenotransplantation (hamster-to-rat)

The hamster-into-rat xenograft combination is a so-called difficult concordant combination. Rats do not have natural anti-hamster antibody in sufficient amounts to yield immediate hyperacute rejection as observed in concordant combinations; however, rejection in un¬ treated recipients occurs within 3 to 4 days, by antibodies in combination with complement. This is visualized in histology by destruction of blood vessels, exsudation and extravasation of erythrocytes, and influx by polymorphonuclear granulocytes; often there are signs of hemorrhage and thrombosis. Once this rejection has been overcome by effective inhibition of antibody synthesis or complement inactivation, a cellular rejection can emerge later on. This is visualized in histology by influx of mononuclear cells, including lymphocytes, lympho- blastoid cells, and macrophages, and destruction of the myocyte parenchyma. The inhibi¬ tion of cellular rejection requires more immunosuppression than that of allografts. Congeni- tally athymic (rnu/rnu) rats lack a competent (thymus-dependent) cellular immune system and generally are unable to reject allografts. Such animals do reject a hamster xenograft within 3 to 4 days in a similar fashion as euthymic rats, indicative that (at least part of) anti- hamster antibody synthesis in rats occurs following a thymus-independent B-cell response. Such recipients are useful in hamster xenografting to evaluate rejection by thymus-indepen¬ dent antibody-mediated rejection.

The heart of a Syrian hamster is heterotopically transplanted in the abdomen of a male Lewis (RTI') rat, with anastomoses between the donor and recipient's aorta and the donor right pulmonary artery to the recipient's inferior vena cava. The graft is monitored daily by palpation of the abdomen. Rejection is concluded in case of cessation of heart beat. Ani¬ mals are weighed weekly. In the present series of experiments, the endpoint is set to 28 days. Animals are subjected to autopsy; apart from the graft, weight and histology is assessed for thymus, spleen, liver, seminal vesicles and testes. Blood is taken and pro¬ cessed to serum for the determination of cytolytic anti-hamster erythrocyte antibody and hemolytic complement activity.

Compounds are dissolved in water and administered daily or twice daily (b.i.d.) orally in a volume of 2 ml/kg body weight. Administration of 5 to 30 mg/kg/day (e.g., 10 mg/kg/day) b.i.d. of a compound of formula I (in particular, 5,6-dihydro-3-phenyl-9-trifluoromethyl-benz- [c]acridine-7-carboxylic acid, 6-fluoro-2-(2'-fluoro-1 ,1'-biphenyl-4-yl)-3-methyl-4-quinoline carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1-indolinyl)-quinoline-4-carboxylic acid or 6-fluoro-3-methyl-2-(4-phenyl-1-indolyl)-quinoline-4-carboxylic acid, sodium salt) results in graft survival without signs of rejection or obvious pathology in both athymic and euthymic recipients through the endpoint of the experiment at 28 days. B. Chronic allograft rejection

The kidney of a male DA (RT1^a) rat is orthotopically transplanted into a male Lewis (RT1¹) recipient. In total 24 animals are transplanted. All animals are treated with cyclosponne A at 7.5 mg/kg/day per os for 14 days starting on the day of transplantation, to prevent acute cellular rejection Contralateral nephrectomy is not performed. Each experimental group treated with a distinct dose of a compound of formula I or placebo comprises six animals

Starting at day 53 to 64 after transplantation, the recipient animals are treated per os for another 69 to 72 days with a compound of formula I or receive placebo. At 14 days after transplantation animals are subjected to graft assessment by magnetic resonance imaging (MRI) with perfusion measurement of the kidneys (with comparison of the grafted kidney and the own contralateral kidney). This is repeated at days 53 to 64 after transplantation and at the end of the experiment. The animals are then autopsied. Rejection parameters such as MRI score, relative perfusion rate of the grafted kidney and histologic score of the kidney allograft for cellular rejection and vessel changes are determined and statistically analyzed Administration of a compound of formula I, e.g. 5,6-dιhydro-3-phenyl-9-trιfluoro- methyl-benz[c]acrιdιne-7-carboxyhc acid, 6-fluoro-2-(2'-fluoro-1 ,1'-bιphenyl-4-yl)-3-methyl- 4-quιnolιne carboxylic actd, 6-fluoro-3-methyl-2-(4-phenyl-1-ιndolιnyl)-quιnolιne-4-carboxylιc acid or 6-fluoro-3-methyl-2-(4-phenyl-1 -ιndolyl)-quιno!ιne-4-carboxylιc acid, sodium salt, at a dose of 2.5 to 5 mg/kg in this rat kidney allograft model yields a reduction in above mentioned rejection parameters.

Claims

WHAT IS CLAIMED IS:

1. Use of a compound of formula

wherein

R\ R², R³ and R⁴ are independently H, halogen, CF₃, d-dalkyl, S-CH₃ or S(0)_m-Ci-Csalkyl, at least two of R¹, R², R³ and R⁴ being H;

R^s is CO(O)H or CO(O)C₂-C₄alkylene-NR 8^βrRι9^M.

R^b is H or Cι-C₃alkyl or when R i7' : is, A', A^< or A^J, also -CN, -NR β^βRr-,9^s, -OR^lu, -SR^,U, -N0₂, -CF₃

-OCF₃ or -SCF₃; R⁷ is a radical of formula A¹, A², A³ or B

(A¹) (A²) (A³) (B) wherein

R¹¹ is H, halogen, unsubstituted or halogen substituted d-C₃alkyl, -NR⁸R⁹, -OC_rC₃alkyi or

-Sd-C₃alkyl; R¹² is aryl or heteroaryl which are optionally substituted by one or more substituents selected from H, halogen, unsubstituted or halogen substituted d-C₃alkyl, -NR⁸R⁹, -OR¹⁰ and -SR¹⁰; R¹³ and R¹⁴ independently are H or d-C₃alkyl;

R¹⁵ is d-C₁₂alkyl, C₆cycloalkyl, C₄heterocycloalkenyl, aryl, aralkyl, O-aryl, O-aralkyl, S(0)_m-aryl or S(O)_m-aralkyl, wherein m is 0, 1 or 2 and aryl and aralkyl are optionally substi¬ tuted by one or more substituents selected from H, halogen, unsubstituted or halogen sub¬ stituted C_rC₅alkyl, C,-C₅alkoxy, N0₂ and OH; R¹⁶ is H, halogen, unsubstituted or halogen substituted d-C₅alkyl, Ci-C₅alkoxy, N0₂ and

OH; X is -N(R¹⁰)-, -O-, -S- or -CH=CH-;

Z is -C(R⁸)(R⁹)-, wherein R⁸ and R⁹ independently are H or d-C₃alkyl; or

R⁶ and R⁷ together form a radical of formula C

wherein

R¹⁷ and R¹⁸ are H or taken together are S;

R⁸ and R⁹ are independently H or d-C₃alkyl; or R⁸ and R⁹ together form a C₄- or C₅alkylene which is optionally interrupted by -NH-, -N(CH₃)- or -0-; R¹⁰ is H or Cι-C₃alkyl; m is 0, 1 or 2; with the following provisos for compounds wherein R⁷ is a radical of formula B

(a) R¹, R² and R³ cannot ail be H;

(b) R¹⁵ cannot be C₆cycloalkyl when R⁵ ts CO(0)(CH₂)rN(CH₃)₂, R³ is CH₂CH₃ or R² is Cl;

(d) when R³ is CH₃, then R² cannot be Cl; including their pharmaceutically acceptable salts and prodrug forms in the manufacture of a medicament for treating or preventing (i) chronic rejection of an allograft or (ii) hyperacute, acute or chronic rejection of a xenograft.

2. The use according to claim 1 , wherein the compound has the formula la, lb or Ic

(lb)

or the formula II

or the formula

wherein

R¹, R², R³, R⁴, R⁵, R⁶, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, X, Y and Z have the meanings according to claim 1.

3. Use of a compound of formula I according to claim 1 , in free form or in pharmaceutically acceptable salt form, for treating or preventing chronic rejection of an allograft or hyperacute, acute or chronic rejection or a xenograft.

4. The use according to claim 1 or 3, wherein the compound is 5,6-dihydro-3-phenyl-9-trifluoromethyl-benz[c]acπdine-7-carboxylιc acιd, 6-fluoro-2-(2'-fluoro-1 ,1 '-biphenyl-4-yl)-3-methyl-4-quιnoiιne carboxylic acid, 6-f luoro-3-methyl-2-(4-phenyl-1 -indolinyl)-quιnoline-4-carboxylιc acid or 6-fluoro-3-methyl-2-(4-phenyl-1-indolyl)-quinoline-4-carboxyiιc acιd or a pharmaceutically acceptable salt form thereof.

5. The use according to claim 1 or 3, wherein the compound is in the sodium salt form.

6. Use of a compound of formula I according to claim 1 , in the manufacture of a medicament for treating or preventing chronic graft rejection.

7. Use according to claim 1 , wherein said medicament is administered concomitantly or in sequence with a second drug, said second drug being an immunosuppressive drup or an anti-inflammatory agent.

8. A pharmaceutical composition comprising a pharmaceutically effective amount of a compound of formula I according to claim 1 in free form or in pharmaceutically acceptable salt form together with a pharmaceutically acceptable diluent or carrier, for use in the treatment or prevention of (i) chronic rejection of an allograft, or (ii) hyperacute, acute, or chronic rejection of a xenograft.

9. The composition according to claim 8 wherein the compound is 5,6-dihydro-3-phenyl-9-trifluoromethyl-benz[c]acridine-7-carboxylic acid, 6-fluoro-2-(2'-fluoro-1 ,1'-biphenyl-4-yl)-3-methyl-4-quinoline carboxylic acid, 6-fluoro-3-methyl-2-(4-phenyl-1 -indolinyl)-quinoline-4-carboxylic acid or 6-fluoro-3-methyl-2-(4-phenyl-1-indolyl)-quinoline-4-carboxylic acid in free acid or pharmaceutically acceptable salt form.