Peptides as inhibitors of fibrous matrix accumulation

Abstract

The present invention relates to peptides that inhibit the overproduction and / or accumulation of extracellular matrix in organs or tissues. The peptides of the present invention have the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly, and Ac-Gly, and Xb is selected from Glu and Glu-NH2. They can be used as both linear and cyclic peptides to inhibit the overproduction and accumulation of extracellular matrix in organs or tissues. In particular, the peptides disclosed herein can be used to treat fibrotic conditions characterized by the overaccumulation of extracellular matrix, such as liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, ischemic heart disease, heart failure, diabetic nephropathy, glomerulonephritis, myelofibrosis, and various types of cancer, including breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas, and fibrosarcomas.

Description

Detailed Description of the Invention

[0001] The present invention relates to peptides that inhibit the overproduction and / or overaccumulation of extracellular matrix in organs or tissues. The peptides of the present invention have the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and can inhibit the overproduction and overaccumulation of extracellular matrix in organs or tissues both as linear peptides and as cyclic peptides. In particular, the peptides disclosed herein can be used to treat fibrotic conditions characterized by the overaccumulation of extracellular matrix, such as liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, ischemic heart disease, heart failure, diabetic nephropathy, glomerulonephritis, myelofibrosis, and various types of cancers, such as breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0002] [Background of the invention] The present invention provides novel peptides that can be used to treat conditions associated with excess matrix accumulation in tissues or organs.The therapeutic effect of the present invention results from reducing or preventing the overproduction of extracellular matrix.One possibility includes, but is not limited to, inhibiting TGFβ (transforming growth factor-β) to effectively reduce the TGFβ-induced component of extracellular matrix deposition.

[0003] The cells within an organ are held together through a network of several types of extracellular matrix molecules, including collagen and fibronectin, produced by many cell types, including various subpopulations of fibroblasts. In almost every type of disease, there are changes in the composition or distribution of the matrix. The changes in matrix composition, which occur whenever a fibrotic process is initiated, directly affect the function of fibroblasts by promoting matrix production. These changes also increase fibroblast differentiation, affecting not only the stiffness of the matrix, which further promotes matrix production, but also its responsiveness to profibrotic cytokines.

[0004] TGFβ is a key molecule involved in matrix accumulation. It is produced by various cells, including activated immune cells and fibroblasts, and can enhance matrix production by stimulating the immune response and increasing fibroblast activation to produce matrix. TGFβ is stored in the matrix in an inactive form that needs to be released from the matrix, a process that requires the action of cell receptors called integrins. Some TGFβ can also be released by the action of proteins such as so-called matrix metalloproteases produced by cells without the involvement of integrins. Once released, TGFβ binds to its receptor and initiates a signaling cascade. There is a large variability in the actions of TGFβ, depending on both the available concentration and the cell type involved. TGFβ is considered a major mediator of fibrosis and scar tissue and is also found almost universally in cancer, suggesting its involvement in cancer growth and progression. The fibrogenic actions of TGFβ result from the simultaneous stimulation of matrix protein synthesis, inhibition of matrix degradation, and enhanced turnover and cell-matrix interactions through modulation of integrin receptors that promote the assembly of the extracellular matrix. In fibrotic diseases, overproduction of TGFβ leads to excessive accumulation of extracellular matrix, causing tissue fibrosis and ultimately organ failure. Fibrotic conditions associated with the accumulation of excess extracellular matrix due to overproduction of TGFβ include, for example, liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, and various types of cancer, such as breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, central nervous system cancer, uterine fibroids, fibromas, fibroadenomas, and fibrosarcomas.

[0005] Furthermore, many of the major cell-cell and cell-matrix interactions that regulate fibrosis are mediated by cell adhesion receptors called integrins, and the integrin family appears to be key regulators of chronic inflammation and fibrosis. Fibrosis models in multiple organs have shown that integrins have a profound effect on the fibrotic process and are upregulated in various types of fibrosis, including liver, kidney, and skin fibrosis. In addition to their direct effects on cell proliferation and survival, integrins have been found to be able to activate latent TGFβ. Preclinical data suggest that integrin targeting may be a promising treatment for fibrotic diseases, although little is currently known about the risks of these interventions. Recently, strategies to manipulate integrins, such as antibody blockade and small molecule inhibitors, have been used in research aimed at antifibrotic therapies.

[0006] European Patent EP 0494264 B1 provides a method for treating or preventing the progression of pathologies characterized by accumulation of extracellular matrix components by providing an agent that inhibits the activity of transforming growth factor beta (TGFβ), which is an anti-TGFβ antibody or an Arg-Gly-Asp (RGD)-containing peptide of 4-50 amino acids in length. Conditions that can be treated with such methods include various fibrotic diseases, glomerulonephritis, adult respiratory distress syndrome, liver cirrhosis, fibrotic cancer, pulmonary fibrosis, arteriosclerosis, post-myocardial infarction, myocardial fibrosis, restenosis after angioplasty, renal interstitial fibrosis and scarring.

[0007] US Patent US 7713924 B2 relates to methods and compositions for reducing and preventing excess accumulation of extracellular matrix using a combination of agents that inhibit TGFβ, alone or in combination with agents that degrade excess accumulated extracellular matrix. Treatable conditions can be fibrotic diseases and scars resulting from excess accumulation of extracellular matrix. The inhibitor composition can include two or three agents, the first one or two of which can be inhibitors of aldosterone, inhibitors of angiotensin II, anti-TGFβ antibodies, inhibitors of renin, proteoglycans and ligands of TGFβ receptors, and the third agent is a PAI inhibitor.

[0008] The object of the present invention is to provide novel peptides and / or pharma- ceutically acceptable salts thereof that can be used as pharma- ceutically active agents, in particular for the treatment of fibrotic conditions associated with excessive matrix deposition, as well as compositions comprising at least one of these peptides and / or a pharma- ceutically acceptable salt thereof as a pharma- ceutically active ingredient. The object of the invention is solved by the teaching of the independent claims. Further advantageous features, aspects and details of the invention are evident from the dependent claims, the description, the drawings and the examples of the present application. Summary of the Invention

[0009] [Brief Description of the Invention] The present invention provides novel peptides that can be used to treat conditions associated with excess matrix accumulation in tissues or organs. The therapeutic effects of the present invention result from the reduction or prevention of excess matrix production and accumulation. In addition, the peptides may act directly through TGFβ or by interacting with cell surface receptors that have not yet been fully characterized. Because matrix accumulation contributes to the decline of organ function in several diseases, we propose that these novel peptides reduce matrix accumulation, thereby reducing the decline in function.

[0010] Thus, the present invention provides peptides consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and pharma-ceutically acceptable salts thereof. A preferred embodiment of the present invention relates to peptides consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and pharma-ceutically acceptable salts thereof. SEQ ID NO: 2 refers to the pentapeptide Gly-Leu-Gln-Gly-Glu (GLQGE).

[0011] Another preferred embodiment of the invention relates to a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is Ac-Gly and Xb is Glu, and to its pharma- ceutically acceptable salts (SEQ ID NO: 3). A more preferred embodiment of the invention relates to a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is Glu and Xb is Glu-NH2, and to its pharma- ceutically acceptable salts (SEQ ID NO: 4). An even more preferred embodiment of the invention relates to a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Glu and Xb is Glu, and Glu is linked to Gly to form a cyclic peptide (SEQ ID NO: 5):

[0012] [ka] The present invention relates to a peptide which forms the following formula:

[0013] A further preferred embodiment of the invention comprises the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0014] [ka] The present invention relates to a peptide which forms the following formula:

[0015] Another embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.A further embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. A preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a cyclic peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu, and Glu is linked to GIy to form a cyclic peptide (SEQ ID NO: 5):

[0016] [ka] and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.

[0017] Another preferred embodiment of the invention is a cyclic peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0018] [ka] and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.

[0019] In another aspect, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a particular aspect, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a preferred embodiment, the present invention provides a peptide, and / or a pharma- ceutically acceptable salt thereof, consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO:3), or where Xa is Gly and Xb is Glu-NH2 (SEQ ID NO:4), for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a preferred embodiment, the present invention provides a peptide, and / or a pharma- ceutically acceptable salt thereof, consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu, where Glu is linked to Gly to form a cyclic peptide (SEQ ID NO:5):

[0020] [ka] In a more preferred embodiment, the present invention provides a peptide which forms a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly, Xb is Glu and Pro is linked to Glu, and / or a pharma-ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in a tissue and / or organ:

[0021] [ka] and / or pharma- ceutically acceptable salts thereof.

[0022] Preferably, said fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, ischemic heart disease, heart failure, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0023] <Detailed Description of the Invention> The inventors have identified a sequence of five amino acids Gly-Leu-Gln-Gly-Glu or one-letter code GLQGE that is able to reduce matrix accumulation in models of chemically induced liver fibrosis in both cyclic and linear mice, showing a surprisingly strong effect compared to similar sequences known in the prior art. In particular, the inventors discovered that both the N-terminal acetylated form Ac-Gly-Leu-Gln-Gly-Glu (SEQ ID NO: 3) and the C-terminal amidated form Gly-Leu-Gln-Gly-Glu-NH2 (SEQ ID NO: 4) are able to reduce matrix accumulation in a chemically induced model of liver fibrosis in mice (Figures 1 and 2), showing better effects compared to the control peptides Ac-Gly-Leu-Asn-Gly-Glu (SEQ ID NO: 8), Gly-Leu-Asn-Gly-Glu-NH2 (SEQ ID NO: 9), Ac-Gly-Leu-Hyp-Gly-Glu (SEQ ID NO: 13), Gly-Leu-Hyp-Gly-Glu-NH2 (SEQ ID NO: 14). The sequences Gly-Leu-Asn-Gly-Glu (SEQ ID NO: 7) and Gly-Leu-Hyp-Gly-Glu (SEQ ID NO: 12) are known to be part of sequences that bind to collagen-binding integrins.

[0024] Furthermore, cyclic Gly-Leu-Gln-Gly-Glu (SEQ ID NO: 5) showed a stronger effect compared to the linear form of the peptide of the same sequence, i.e., N-terminal acetylation or C-terminal amidation, and also compared to cyclic Gly-Leu-Asn-Gly-Glu (SEQ ID NO: 10) and cyclic Gly-Leu-Hyp-Gly-Glu (SEQ ID NO: 15). Notably, the cyclic form containing proline Pro-Gly-Leu-Gln-Gly-Glu (SEQ ID NO: 6) was also able to significantly reduce collagen accumulation with a stronger effect compared to Pro-Gly-Leu-Asn-Gly-Glu (SEQ ID NO: 11) and Pro-Gly-Leu-Hyp-Gly-Glu (SEQ ID NO: 16), but the effect was weaker when compared to cyclic Gly-Leu-Gln-Gly-Glu (SEQ ID NO: 5). These peptides can be used to treat fibrotic conditions associated with excessive matrix accumulation, since matrix accumulation contributes to the decline of organ function in several diseases. The underlying mechanism could be due to a direct effect of the peptide on cell surface receptors that are not yet fully characterized, or an indirect effect by influencing the amount of or response to TGFβ, which represents a key molecule involved in the progression of several diseases, or a direct effect on one or more cell types that reduces the production of extracellular matrix proteins.

[0025] Thus, the present invention provides peptides consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and pharma-ceutically acceptable salts thereof. A preferred embodiment of the present invention relates to peptides consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and pharma-ceutically acceptable salts thereof. Another preferred embodiment of the present invention relates to peptides consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and pharma-ceutically acceptable salts thereof. A more preferred embodiment of the present invention relates to peptides Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and pharma-ceutically acceptable salts thereof. An even more preferred embodiment of the invention consists of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu, and Glu is linked to Gly to form a cyclic peptide (SEQ ID NO:5):

[0026] [ka] The present invention relates to a peptide which forms the following formula:

[0027] A further preferred embodiment of the invention comprises the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0028] [ka] The present invention relates to a peptide which forms the following formula:

[0029] The term "peptide" refers to a compound composed of a single chain of D- or L-amino acids or a mixture of D- and L-amino acids linked by peptide bonds. In general, the peptides of the invention are most preferably 5-6 amino acids in length.

[0030] The term "cyclic peptide" as used herein refers to the peptide Gly-Leu-Gln-Gly-Glu, and its controls Gly-Leu-Asn-Gly-Glu, Gly-Leu-Hyp-Gly-Glu, in which the amino terminus of the peptide is linked by a peptide bond to the carboxyl terminus of the peptide or to the side chain of the amino acid Glu having a free carboxyl group. The amino terminus of Gly in the peptide Gly-Leu-Gln-Gly-Glu is preferably linked by a peptide bond to the carboxyl terminus of Glu, rather than to the side chain carboxyl group of Glu. Also described herein are the cyclic peptides Pro-Gly-Leu-Gln-Gly-Glu, and its controls Pro-Gly-Leu-Asn-Gly-Glu and Pro-Gly-Leu-Hyp-Gly-Glu, in which the amino terminus of the peptide is linked by a peptide bond to the carboxyl terminus of the peptide or to the side chain of the amino acid Glu having a free carboxyl group. Preferably, the amino terminus of Pro in the peptide Pro-Gly-Leu-Gln-Gly-Glu is linked via a peptide bond to the carboxyl terminus of Glu rather than to the side chain carboxyl group of Glu.

[0031] In the formulas representing selected particular peptide embodiments of the invention, the amino and carboxy terminal groups are often not specifically shown, but are understood to be in the form they will assume at physiological pH values ​​unless otherwise indicated. Thus, the N-terminal H at physiological pH + and C-terminal O -(i.e., betaine type) is understood to exist, although not necessarily specified and shown in either the specific examples or the general formula. In the peptide notation used herein, the left end of the molecule is the amino terminus and the right end is the carboxy terminus, in accordance with standard usage and convention. Of course, base salts and acid addition salts, including those formed at non-physiological pH values, are also included in the compounds of the present invention.

[0032] The term "amino acid" as used herein includes the standard 20 genetically encoded amino acids and their corresponding stereoisomers in the "D" form (as compared to the natural "L" form), omega amino acids, other naturally occurring amino acids, non-conventional amino acids (e.g., α,α-disubstituted amino acids, N-alkyl amino acids, etc.) and chemically derivatized amino acids. When an amino acid is specifically listed, such as "glutamine" or "Gln" or "Q", the term refers to both L-glutamine and D-glutamine unless otherwise indicated. However, the naturally occurring L-form is most preferred. Thus, the L-form of the peptides disclosed herein is preferred, particularly the L-form of Gly-Leu-Gln-Gly-Glu. Other conventional amino acids may also be suitable components of the polypeptides of the invention, so long as the desired functional properties are retained by the polypeptide. In the case of the peptides shown, each encoded amino acid residue is represented, where appropriate, by three letters corresponding to the trivial name of the conventional amino acid. In the present invention, in a peptide of the sequence Gly-Leu-Hyp-Gly-Glu (GLOGE), the common non-proteinogenic amino acid hydroxyproline is abbreviated as Hyp when using the three letter code and as "0" when using the one letter code.

[0033] Peptides according to the invention can be synthesized by several methods, including chemical synthesis. Solid phase synthesis consists of the sequential addition of one or more amino acid residues or suitably protected amino acid residues to a growing peptide chain. Either the amino or carboxyl group of the first amino acid residue is protected by a suitable selectively removable protecting group. For amino acids containing reactive side groups such as lysine, a separate selectively removable protecting group is utilized. Using solid phase synthesis, a protected or derivatized amino acid is attached to an inert solid support via an unprotected carboxyl or amino group. The amino or carboxyl protecting group is then selectively removed, and the next amino acid in the sequence, which has a suitably protected complementary (amino or carboxyl) group, is mixed with the solid support and reacted to form an amide bond with the residue already attached to the solid support. The amino or carboxyl protecting group is then removed from this newly added amino acid residue, and then the next amino acid (suitably protected) is added, and so on. After all the desired amino acids have been linked in the proper sequence, the remaining terminal and side group protecting groups (and the solid support) are removed sequentially or simultaneously to obtain the final desired peptide. The resulting linear peptides can then be reacted to form their corresponding cyclic peptides. Methods for cyclizing peptides are known in the art.

[0034] The term "pharmaceutically acceptable salts" refers to inorganic and organic acid addition salts of a compound. As used herein, the terms "pharmaceutically acceptable" and "physiologically acceptable" and grammatical variations thereof are used interchangeably and refer to a compound that can be administered to a mammal without producing undesirable physiological effects, such as nausea, dizziness, stomach upset, etc. Acids capable of forming salts with peptides include hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, acetic acid, citric acid, oxalic acid, malonic acid, salicylic acid, p-aminosalicylic acid, malic acid, fumaric acid, succinic acid, ascorbic acid, maleic acid, sulfonic acid, phosphonic acid, perchloric acid, nitric acid, formic acid, propionic acid, gluconic acid, lactic acid, tartaric acid, hydroxymaleic acid, pyruvic acid, phenylacetic acid, benzoic acid, p-aminobenzoic acid, p-hydroxybenzoic acid, methanesulfonic acid, ... Inorganic acids include nitrous acid, hydroxyethanesulfonic acid, ethylenesulfonic acid, p-toluenesulfonic acid, naphthylsulfonic acid, sulfanilic acid, camphorsulfonic acid, china acid, mandelic acid, o-methylmandelic acid, hydrogen-benzenesulfonic acid, picric acid, adipic acid, do-tolyltartaric acid, tartronic acid, a-toluic acid, (o,m,p)-toluic acid, naphthylaminesulfonic acid, and other mineral or carboxylic acids well known to those skilled in the art. Preferred are trifluoroacetic acid (TFA), hydrochloric acid, perchloric acid, nitric acid, thiocyanic acid, sulfuric acid, phosphoric acid, acetic acid, propionic acid, oxalic acid, glycolic acid, lactic acid, pyruvic acid, malonic acid, succinic acid, maleic acid, fumaric acid, anthranilic acid, cinnamic acid, naphthalenesulfonic acid, sulfanilic acid, etc. More preferred are hydrochloric acid and trifluoroacetic acid salts. The salts are prepared by contacting the free base form with a sufficient amount of the desired acid to produce the salt in the conventional manner.

[0035] Suitable bases which can form salts with the peptides of the present invention include inorganic bases such as sodium hydroxide, as well as mono-, di-, and trialkyl and arylamines (e.g., triethylamine, diisopropylamine, methylamine, dimethylamine, etc.) and optionally substituted ethanolamines (e.g., ethanolamine, diethanolamine, etc.).

[0036] The peptides of the invention are preferably purified to be substantially free of contaminants. A material is said to be "substantially free of contaminants" when it has been substantially purified from undesirable materials with which it was associated during synthesis, either within a cell or in an in vitro system, to an extent sufficient to render it useful for a desired purpose.

[0037] <Pharmaceutical Composition> An embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu, Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. A further embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. A preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu, and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a cyclic peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu, and Glu is linked to GIy to form a cyclic peptide (SEQ ID NO: 5):

[0038] [ka] and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the invention is a cyclic peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0039] [ka] and / or a pharma- ceutically acceptable salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.

[0040] More specifically, the present invention relates to a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. A further embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), where Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. A preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Glu and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent. Another preferred embodiment of the present invention provides a pharmaceutical composition comprising a peptide of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Glu and Xb is Glu and Glu is linked to Gly to form a cyclic peptide (SEQ ID NO: 5):

[0041] [ka] and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.

[0042] Another preferred embodiment of the invention is a cyclic peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0043] [ka] and / or a pharma- ceutically acceptable non-toxic salt thereof, together with at least one pharma- ceutically acceptable vehicle, excipient and / or diluent.

[0044] Pharmaceutical compositions are designed to facilitate administration of the peptides of the invention in an effective manner. Typically, the peptides of the compositions of the invention are dissolved or dispersed in a pharma- ceutically acceptable excipient.

[0045] Examples of suitable carriers or excipients include lactose, dextrose, sucrose, glucose, powdered sugar, sorbitol, mannitol, xylitol, starch, acacia gum, xanthan gum, guar gum, tara gum, mesquite gum, fenugreek gum, locust bean gum, ghatti gum, tragacanth gum, inositol, molasses, maltodextrin, extract of Irish moss, breadwah gum, isapol shell mucilage, veegum, larch arabogalactan, calcium silicate, phosphate. Examples of suitable carriers include, but are not limited to, calcium, dicalcium phosphate, calcium sulfate, kaolin, sodium chloride, polyethylene glycol, alginate, gelatin, microcrystalline cellulose, polyvinylpyrrolidone, cellulose, water, saline, syrup, polyacrylic acids such as methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, carbopols such as Carbopol 941, Carbopol 980, Carbopol 981, and gum bases such as Pharmagum™ (SPI Pharma Group; New Castle, Del.), and the like. Typically, the compositions of the present invention comprise from about 10% to about 90% by weight of a vehicle, excipient, or combination thereof.

[0046] Preferably, the pharmaceutical composition comprises from about 0.001% to about 90% by weight, preferably from about 0.01% to about 75% by weight, more preferably from about 0.1% to 50% by weight, and even more preferably from about 0.1% to 10% by weight of the cyclic peptides of the present invention or combinations thereof, with the remainder consisting of suitable pharmaceutical carriers, excipients, and / or diluents.

[0047] The pharmaceutical composition can be formulated into the form of powder, granule, tablet, capsule, suspension, emulsion, syrup, oral dosage form, external preparation, suppository, or sterile injectable solution such as aerosolized in the usual manner. When formulated, it can be prepared using diluents or excipients such as commonly used fillers, extenders, binders, wetting agents, disintegrating agents, surfactants, etc.

[0048] In the pharmaceutical composition, the solid formulation for oral administration can be a tablet, pill, powder, granule, or capsule. The solid formulation can further include an excipient. The excipient can be, for example, starch, calcium carbonate, sucrose, lactose, or gelatin. In addition, the solid formulation can further include a lubricant, such as magnesium stearate or talc. In the pharmaceutical composition, the best liquid formulation for oral administration can be a suspension, solution, emulsion, or syrup. The liquid formulation can include water or liquid paraffin. The liquid formulation can include, for example, in the case of an excipient, a wetting agent, a sweetener, an aromatic, or a preservative. For the purpose of parenteral administration, the composition containing the peptide of the present invention is preferably dissolved in distilled water, and the pH is preferably adjusted to about 6 to 8. If the peptide is provided in a lyophilized form, lactose can be added to the solution to facilitate the lyophilization process. In such a form, the solution is then sterilized, introduced into a vial, and lyophilized. Useful formulations of the compositions of the present invention for parenteral administration also include sterile aqueous and non-aqueous solvents, suspensions and emulsions. Examples of useful non-aqueous solvents include propylene glycol, polyethylene glycol, vegetable oils, fish oils, and injectable organic esters.

[0049] <Uses of peptides> As used herein, "excessive accumulation of extracellular matrix" means increased deposition of extracellular matrix components, including collagen, laminin, fibronectin and proteoglycans, in tissues as a result of fibrotic disease to an extent that leads to impaired tissue or organ function and ultimately organ failure. The extracellular matrix is ​​a mixture of proteins, proteoglycans, glycoproteins and collagens assembled into a complex superstructure.

[0050] A variety of fibrotic conditions are characterized by the excessive accumulation of extracellular matrix, including, but not limited to, diabetes-related conditions such as glomerulonephritis, acute respiratory distress syndrome (ARDS), diabetic kidney disease, renal fibrosis, pulmonary fibrosis, myocardial fibrosis, cardiac scarring, post-infarction myocardial fibrosis, fibrotic diseases of the liver, liver fibrosis, liver cirrhosis, fibrosclerosis, myelofibrosis, and various types of cancer, as reported below.

[0051] There are also many disease states associated with excess accumulation of extracellular matrix, including, but not limited to, post-myocardial infarction, left ventricular hypertrophy, pulmonary fibrosis, venous occlusive disease, post-spinal cord injury, post-retinal and glaucoma surgery, post-angioplasty restenosis and renal interstitial fibrosis, arteriovenous graft failure, arteriosclerosis, and excessive scarring, such as keloid scars, hypertrophic scars, and scars resulting from injury, burns, or surgery.

[0052] In the liver, almost all diseases lead to the activation of fibroblasts and the production of matrix. In turn, this matrix prevents cell renewal and disrupts the microarchitecture, causing symptoms of decreased function and increased portal pressure characteristic of liver failure. In the lungs, the accumulation of matrix prevents the proper exchange of oxygen and carbon dioxide, causing chronic respiratory failure and, in the most severe cases, asphyxiation. In the heart, remodeling, which occurs after an ischemic attack or in the context of cardiomyopathy, leads to the development of scars made of matrix that cannot contribute to the contraction of the myocardium, which in severe forms expand instead of contracting, thus leading to heart failure. In diabetic nephropathy, the accumulation of extracellular matrix in the functional units called glomeruli similarly reduces renal function.

[0053] The term "cancer" refers to any of a variety of malignant neoplasms characterized by the proliferation of anaplastic cells that tend to destroy organ functions or invade surrounding tissues and metastasize to new body sites. It is known in the art that cancer progression is associated with the excessive accumulation of extracellular matrix components and changes in the composition of the extracellular matrix. Examples of different types of cancer suitable for treatment using the present invention include, but are not limited to, breast cancer, prostate cancer, uterine cancer, pancreatic cancer or colon cancer, skin cancer, blood cell cancers such as lymphoma and leukemia, cancers of the central nervous system such as glioblastoma multiforme, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0054] As used herein, preferred fibrotic conditions characterized by excessive accumulation of extracellular matrix in tissues and / or organs are selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, ischemic heart disease, heart failure, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0055] From the art, it is known that many cytokines are involved in the fibrotic process. TGFβ is considered an important mediator of fibrosis and scar tissue and is also found almost universally in cancer, suggesting its involvement in cancer growth and progression. The fibrogenic action of TGFβ results from the simultaneous stimulation of matrix protein synthesis, inhibition of matrix degradation, and turnover. In fibrotic diseases, overproduction of TGFβ leads to excessive accumulation of extracellular matrix, causing tissue fibrosis and ultimately organ failure. Fibrotic conditions associated with the accumulation of excess extracellular matrix due to overproduction of TGFβ are, for example, liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, diabetic nephropathy, glomerulonephritis, and various types of cancer.

[0056] Blocking the action of TGFβ with agents such as antibodies has been shown to have therapeutic effects on fibrosis in various tissues and to interfere with the overproduction of TGFβ. As used herein, "inhibition of TGFβ" includes inhibition of TGFβ production, which leads to overproduction and overaccumulation of extracellular matrix deposits, and inhibition of TGFβ activity, which leads to, for example, overdeposition of extracellular matrix deposits, regardless of the mechanism of TGFβ activity or overproduction. This inhibition can be caused directly, for example, by binding to TGFβ or its receptor, or indirectly, by inhibiting a pathway that leads to TGFβ production, such as the integrin pathway. The inhibition causes a decrease in the extracellular matrix production activity of TGFβ, regardless of the exact mechanism of inhibition.

[0057] Reduction of extracellular matrix production by other mechanisms, either associated with other cytokines or not associated with any cytokine, is also possible. In an attempt to find novel peptides as therapeutic agents for the efficient treatment of tissue fibrosis, the inventors compared the activity of peptides with the sequences Gly-Leu-Hyp-Gly-Glu (GLOGE) and Gly-Leu-Asn-Gly-Glu (GLNGE) with Gly-Leu-Gln-Gly-Glu (GLQGE). GLNGE is a short sequence contained in R1R2 that has been shown to reduce collagen accumulation. GLOGE is a sequence known to be part of the sequence that binds to collagen-binding integrins.

[0058] Animal models of liver fibrosis have been widely used to study the mechanisms underlying liver fibrosis and the effects of various drugs on its progression. Liver fibrosis is characteristic of acute or chronic injury to the liver in response to diverse metabolic, viral, and toxic stimuli. Excessive deposition of extracellular matrix accumulation proteins, including hyaluronic acid, laminin, and collagen, occurs during fibrogenesis along with activation of hepatic stellate cells (HSCs). Activated HSCs produce transforming growth factor TGFβ, which induces collagen production leading to accumulation of extracellular matrix, and also upregulate tissue inhibitor of metalloproteinases. CCl4 is an experimental reagent characterized by its toxicity in causing acute liver injury and liver fibrosis and is widely used in liver-related research. It is well known in the state of the art that intraperitoneal administration of CCl4 induces liver injury and simultaneously induces the production and release of TGFβ, which in turn enhances the synthesis of hepatic collagen types I, III, and IV mRNA and protein. Accordingly, it has been found that in vivo neutralization of TGFβ reduces collagen mRNA.

[0059] Experiments carried out on CCl4-induced liver fibrosis in mice (Example 2, Figure 1 and Example 3, Figure 2) showed that linear peptides of the sequences Gly-Leu-Gln-Gly-Glu-NH2 and Ac-Gly-Leu-Gln-Gly-Glu were able to inhibit collagen deposition. Surprisingly, the inhibitory activity of Gly-Leu-Gln-Gly-Glu-NH2 (linear GLQGE-NH2) and Ac-Gly-Leu-Gln-Gly-Glu (linear Ac-GLQGE) was stronger than that of the corresponding acetylated or amidated forms of the controls Gly-Leu-Hyp-Gly-Glu (linear GLOGE) and Gly-Leu-Asn-Gly-Glu (linear GLGE).

[0060] This finding is supported by the observation that the linear sequence Gly-Leu-Gln-Gly-Glu-NH2 (linear GLQGE-NH2) efficiently inhibited unstimulated TGFβ expression in mouse hepatocytes (data not shown), whereas the linear sequences of the two controls Gly-Leu-Asn-Gly-Glu-NH2 (GLNGE-NH2) and Gly-Leu-Hyp-Gly-Glu-NH2 (GLOGE-NH2) were ineffective.

[0061] Furthermore, the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) had a greater inhibitory effect on collagen accumulation in chemically induced chronic liver injury in mice (Figure 1) compared with the linear Gly-Leu-Gln-Gly-Glu-NH2 or Ac-Gly-Leu-Gln-Gly-Glu. Similar to the linear peptides, cyclic Gly-Leu-Asn-Gly-Glu (cyclic GLNGE) and Gly-Leu-Hyp-Gly-Glu (cyclic GLOGE) failed to inhibit collagen accumulation.

[0062] Thus, peptides with the sequence Gly-Leu-Gln-Gly-Glu in both linear and cyclic forms appear to have a greater ability to inhibit collagen accumulation in chemically induced liver injury than both the Gly-Leu-Asn-Gly-Glu and Gly-Leu-Hyp-Gly-Glu sequences and may be used as therapeutic agents to inhibit the progression of fibrosis.

[0063] In particular, the cyclic peptides Gly-Leu-Gln-Gly-Glu and Pro-Gly-Leu-Gln-Gly-Glu (Figure 2) are considered to be of particular interest as therapeutic agents, since both showed strong inhibitory effects on collagen accumulation. Indeed, cyclic peptides have the advantage of being resistant to hydrolysis by exopeptidases due to the absence of both amino and carboxyl termini, and also resistant to endopeptidases due to their less structural flexibility than linear peptides. In particular, cyclic peptides, due to their structural rigidity, work very well as receptor agonists or antagonists. Moreover, compared to small molecules such as antibodies, the size of the molecule is smaller but can be more selective and therefore more advantageous. The cyclic peptide Gly-Leu-Gln-Gly-Glu was also able to reduce collagen accumulation in an experimental model of pulmonary fibrosis (Figure 4), confirming the ability of this peptide to reduce matrix accumulation and suggesting that it may be effective in other diseases associated with increased extracellular matrix mass.

[0064] Thus, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a particular embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a preferred embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a preferred embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in a tissue and / or organ. In a preferred aspect, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is GIy and Xb is Glu and Glu is linked to GIy to form a cyclic peptide (SEQ ID NO: 5):

[0065] [ka] In a more preferred embodiment, the present invention provides a peptide which forms a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly, Xb is Glu and Pro is linked to Glu, and / or a pharma-ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in a tissue and / or organ:

[0066] [ka] and / or pharma- ceutically acceptable salts thereof.

[0067] The cyclic peptides disclosed herein were also able to prevent the growth of various types of cancer. In fact, the cyclic peptide Gly-Leu-Gln-Gly-Glu (HCl salt) was able to significantly reduce the size of melanoma tumors in mice (Figure 3). Furthermore, the cyclic peptide Gly-Leu-Gln-Gly-Glu (HCl salt) was able to suppress the growth of breast cancer in mice (Figure 5).

[0068] A preferred embodiment of the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma. In a particular embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Gly and Ac-Gly and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma. In a preferred embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.In a preferred embodiment, the present invention provides a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, for use in the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas. In a preferred embodiment, the present invention provides a cyclic peptide (SEQ ID NO: 5) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly, Xb is Glu and Glu is linked to Gly, for use in the treatment of fibrotic conditions characterised by excessive accumulation of extracellular matrix in tissues and / or organs.

[0069] [ka] and / or a pharma- ceutically acceptable salt thereof, wherein the condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas. In a more preferred embodiment, the present invention provides a peptide comprising the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly, Xb is Glu, and Pro is linked to Glu to form a cyclic peptide (SEQ ID NO: 6):

[0070] [ka] and / or a pharmaceutically acceptable salt thereof, wherein the condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma.

[0071] The peptides or pharmaceutical compositions disclosed herein may be administered by a variety of routes to subjects, such as mammals, including rats, mice, dogs, cows, horses, monkeys, and humans. The peptides disclosed herein can be suspended in a physiologically compatible pharmaceutical carrier, such as saline, phosphate buffered saline, etc., to form a physiologically acceptable aqueous pharmaceutical composition for administration to a subject. Parenteral vehicles include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, and lactated Ringer's solution. Other substances, such as antibacterial agents, can be added as necessary.

[0072] Methods of administration of the peptides disclosed herein are those known in the art for therapeutic agents and can be applied to mucosal surfaces, for example, intravenously, intraperitoneally, intramuscularly, intradermally, and epidermally, including subcutaneously and intradermally, orally, or by intranasal administration, for example, using inhalation of an aerosol suspension, and by implantation into muscle or other tissues of a subject. Suppositories and topical formulations are also contemplated.

[0073] In general, when it is desired to increase the absorption of the peptides of the present invention via ocular, buccal, transdermal, rectal, nasal or oral inhalation, certain penetration enhancers are used. These enhancers may include chelating agents such as EDTA, citric acid, N-acyl derivatives of collagen, enamines (N-amino-N-acyl derivatives of β-diketones), etc. Surfactants can also be used to enhance penetration. Surfactants include sodium lauryl sulfate, polyoxyethylene-9-lauryl ether and polyoxyethylene-20-cetyl ether. Bile salts and derivatives are also known to enhance the penetration of peptides, and these include sodium deoxycholate, sodium glycocholate, sodium taurocholate, sodium taurodihydrofusidate and sodium glycodihydrofusidate. Yet another type of penetration enhancer useful in the compositions of the present invention includes keratin fatty acids and derivatives such as oleic acid, caprylic acid, capric acid, acylcarnitines, acylcholines and mono- and diglycerides. Non-surfactants are also useful as penetration enhancers. The penetration enhancer can be used in a solution containing the compound of the present invention, where the compound and the penetration enhancer are in a sterilized pharma- ceutically acceptable solution that can be administered, for example, by nasal administration. Alternatively, the penetration enhancer can be included in a kinetic formulation that can be administered as an aerosol by suspending the particulate matter in an air stream and having the patient inhale the suspended particles. Such a kinetic formulation can be administered by a dry powder inhaler.

[0074] Thus, the peptide compounds of the invention may also be administered by human medical personnel and veterinarians. Another related aspect of the invention is a method for administering the compounds of the invention in combination with other therapies, such as conventional drug therapy chemotherapy, for cancer and for controlling the establishment of metastases. Administration of the peptides of the invention is usually performed before, during or after chemotherapy.

[0075] The term "therapeutically effective amount" refers to the amount of linear or cyclic peptide and pharmaceutical composition disclosed herein that can achieve a therapeutic effect in a subject in need thereof.For example, a therapeutically effective amount of a cyclic peptide or combination of cyclic peptides is an amount that can prevent or reduce the excess accumulation of extracellular matrix in susceptible tissues and organs, or one or more associated symptoms.

[0076] Those skilled in the art will recognize that potency, and therefore "therapeutically effective" amount, may vary for the compounds of the present invention.However, as shown by the present specification, those skilled in the art can easily evaluate the potency of candidate peptides of the present invention.Potency can be measured by various means, including inhibition of TGFβ production, collagen accumulation, inhibition of cell adhesion to vitronectin, fibronectin and / or collagen, and similar assays.

[0077] A therapeutically effective amount of a peptide or pharmaceutical composition of the invention is typically an amount of peptide sufficient to achieve a plasma concentration of about 0.1 nanogram (ng) / milliliter (ml) to about 200 μg / ml, preferably about 1 ng / ml to about 100 μg / ml, when administered in a physiologically acceptable composition. Dosage per body weight can vary from 10 mg / kg to 100 mg / kg, preferably 20 mg / kg to 80 mg / kg, more preferably 20 mg / kg to 60 mg / kg, even more preferably 20 mg / kg to 40 mg / kg, in one or more administrations per day, for one or several days.

[0078] The preferred dosage regimen and mode of administration of the peptide or pharmaceutical composition of the present invention may vary depending on the severity of the accumulation of extracellular matrix and the resulting impairment of tissue or organ function, the subject's health, previous medical history, age, weight, height, sex, response to treatment, and the judgment of the treating physician.The preferred dosage regimen and mode of administration may be appropriately selected by those skilled in the art.Initially, such parameters are easily determined by a skilled practitioner using appropriate tests in animal models for safety and efficacy, and in human subjects during clinical trials of candidate therapeutic preparations.Suitable animal models of human fibrotic conditions are known in the art.

[0079] After administration, the efficacy of treatment using the method of the present invention is evaluated by various methods, including biopsy of kidney, lung or liver or another tissue target with excess matrix accumulation to detect the amount of accumulated extracellular matrix. Lack of significant excess accumulation of extracellular matrix or a reduction in the amount or expansion of extracellular matrix in the tissue or organ indicates a desirable therapeutic response in the subject. It is preferable to use a non-invasive procedure to detect the therapeutic response. For example, changes in TGFβ activity can be measured in plasma samples before and after treatment with a therapeutic compound, and biopsy tissue can be used to individually isolate diseased tissues used for RNA isolation. The mRNA transcripts of TGFβ, and / or extracellular matrix components (such as collagen) are then determined using reverse transcriptase polymerase chain reaction (RT-PCR).

[0080] "Administering" or "administration" includes, for example, but is not limited to, delivery by intravenous, intramuscular, intradermal or subcutaneous routes, or by injectable forms such as nasal drops or aerosols for inhalation, or mucosal routes as ingestible solutions, capsules or tablets.

[0081] "Reducing excess accumulation of extracellular matrix" means, for example, preventing excess accumulation of extracellular matrix in a tissue, organ, or wound site, preventing further deposition of extracellular matrix, and / or reducing the amount of excess accumulated matrix already present to maintain or restore the function or appearance of the tissue or organ.

[0082] Furthermore, according to a preferred embodiment, the present invention also provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0083] According to an even more preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO:1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein accumulation of extracellular matrix in the tissues and / or organs is prevented or reduced from therapeutic levels, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0084] Another embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Gly and Ac-Gly and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0085] Another preferred embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO:1), wherein Xa is selected from Gly and Ac-Gly and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a therapeutic level, and the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0086] A further embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels. A further preferred embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a therapeutic level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0087] A further embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels. A further preferred embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a therapeutic level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0088] A further embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of forming a cyclic peptide (SEQ ID NO: 5) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu and Glu is linked to Gly:

[0089] [ka] and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from therapeutic levels.

[0090] A further preferred embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by an excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of producing a cyclic peptide (SEQ ID NO: 5) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu and Glu is linked to Gly:

[0091] [ka] and / or a pharmaceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from a treatment level, and the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma.

[0092] A further embodiment of the present invention relates to a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of preparing a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu:

[0093] [ka] and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from therapeutic levels.

[0094] A further preferred embodiment of the present invention relates to a method for the treatment of fibrotic conditions characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of producing a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu:

[0095] [ka] and / or a pharmaceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from a treatment level, and the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma.

[0096] In another embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0097] In another preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO: 1), wherein Xa is selected from Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0098] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0099] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from therapeutic levels.

[0100] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of administering to a subject a cyclic peptide (SEQ ID NO: 5) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly, Xb is Glu and Glu is linked to Gly:

[0101] [ka] and / or a pharma- ceutical composition comprising a peptide that forms the formula (I) and / or a pharma- ceutical acceptable salt thereof, and wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from the level at the time of treatment.

[0102] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of preparing a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu:

[0103] [ka] and / or a pharma- ceutical composition comprising a peptide that forms a medicament for treating a pulmonary artery disease, and / or a pharma- ceutical composition comprising a medicament for treating a pulmonary artery disease, and / or a pharma- ceutical composition comprising a peptide that forms ...

[0104] In another embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excess accumulation of extracellular matrix in a tissue and / or organ, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO:1), wherein Xa is selected from Pro-Gly, Gly and Ac-Gly, and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from a treated level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma and fibrosarcoma.

[0105] In another preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excess accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb (SEQ ID NO:1), wherein Xa is selected from Gly and Ac-Gly and Xb is selected from Glu and Glu-NH2, and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a treated level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0106] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excess accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, wherein Xa is Ac-Gly and Xb is Glu (SEQ ID NO: 3), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a treated level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0107] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, the method comprising administering to a patient a therapeutically effective amount of a pharmaceutical composition comprising a peptide consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly and Xb is Glu-NH2 (SEQ ID NO: 4), and / or a pharma- ceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissues and / or organs is reduced from a treated level, the fibrotic condition being selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

[0108] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of administering to a subject a cyclic peptide (SEQ ID NO: 5) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Gly, Xb is Glu and Glu is linked to Gly:

[0109] [ka] and / or a pharmaceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from a treated level, and the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma, and fibrosarcoma.

[0110] In a further preferred embodiment, the present invention provides a method for the treatment of a fibrotic condition characterized by excessive accumulation of extracellular matrix in tissues and / or organs, comprising the step of preparing a cyclic peptide (SEQ ID NO: 6) consisting of the general sequence Xa-Leu-Gln-Gly-Xb, where Xa is Pro-Gly and Xb is Glu, and Pro is linked to Glu:

[0111] [ka] and / or a pharmaceutically acceptable salt thereof, wherein the accumulation of extracellular matrix in the tissue and / or organ is reduced from a treated level, and the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, heart failure, ischemic heart disease, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibroma, fibroadenoma, and fibrosarcoma. [Brief description of the drawings]

[0112] [Figure 1]Prevention of fibrosis progression by proline-containing cyclic and amidated linear peptides. To induce liver fibrosis, mice were injected with CCl4 for 6 weeks. Starting on day 32, mice received daily intraperitoneal injections of 25 mg / kg / mouse / day peptide in 0.9% NaCl for a total of 10 days. Mice treated with CCl4 also received NaCl 0.9%. The healthy control group (CT) received only 0.9% NaCl. N=4 / 10 / 8 / 5 / 10 / 8 / 11 / 7 in two experiments. The following peptide: cyclic Pro-Gly-Leu-Gln-Gly-Glu (cyclic PGLQGE) was tested in CCl4-treated mice and compared with two controls: cyclic Pro-Gly-Leu-Asn-Gly-Glu (cyclic CT1+P: cyclic PGLNGE) and cyclic Pro-Gly-Leu-Hyp-Gly-Glu (cyclic CT2+P: cyclic PGLOGE). Linear Gly-Leu-Gln-Gly-Glu-NH2 (Linear GLQGE-NH2) was also tested and compared with two controls: Linear Gly-Leu-Asn-Gly-Glu-NH2 (Linear CT1-NH2: Linear GLNGE-NH2) and Linear Gly-Leu-Hyp-Gly-Glu-NH2 (Linear CT2-NH2: Linear GLOGE-NH2). *p<0.05. Assessed by t-test. Data are presented as mean ± SEM. [Diagram 2]Prevention of fibrosis progression by cyclic and acetylated linear peptides. To induce liver fibrosis, mice were injected with CCl4 for 6 weeks. Starting on day 32, mice received daily intraperitoneal injections of peptides at 25 mg / kg / mouse / day in 0.9% NaCl for a total of 10 days. Mice treated with CCl4 also received NaCl 0.9%. The healthy control group (CT) received only NaCl 0.9%. N=5 / 18 / 9 / 9 / 6 / 5 / 4 / 4 in two experiments. The following peptide: cyclic Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) was tested in CCl4-treated mice and compared to two controls: cyclic Gly-Leu-Asn-Gly-Glu (cyclic CT1: cyclic GLNGE) and cyclic Gly-Leu-Hyp-Gly-Glu (cyclic CT2: cyclic GLOGE). Linear Ac-Gly-Leu-Gln-Gly-Glu (Linear Ac-GLQGE) was also tested and compared with two controls: Linear Ac-Gly-Leu-Asn-Gly-Glu (Linear Ac-CT1: Linear Ac-GLNGE) and Linear Ac-Gly-Leu-Hyp-Gly-Glu (Linear Ac-CT2: Linear Ac-GLOGE). *p<0.05, **p<0.005. Assessed by t-test. Data are presented as mean ± SEM. [Diagram 3] Prevention of cancer growth by cyclic GLQGE in the form of its hydrochloride salt (cyclic GLQGE HCl salt). Mice were subcutaneously injected with B16 melanoma cancer cells. On day 7, a subcutaneous injection of 1 mg of peptide or 0.9% NaCl was administered. On day 12, mice were euthanized and tumors were removed and weighed. N=11 / 11 mice. Data are presented as mean ± SEM. [Figure 4]Prevention of fibrosis progression by the cyclic peptide Gly-Leu-Gln-Gly-Glu (acetate). Pulmonary fibrosis was induced in 6-week-old male C57bl / 6 mice using intratracheal bleomycin injection at a dose of 0.005 units in 50 μl on day 0. Starting on day 11, cyclic Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) was injected subcutaneously at a dose of 1 mg / mouse / day in 0.9% NaCl for a total of 10 days. The control group received only daily injections of 0.9% NaCl. The number of animals in the four groups was N=14 / 10 / 10 / 9 in three experiments. Cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) (acetate) was tested and compared with cyclic Ac-Gly-Leu-Asn-Gly-Glu (cyclic GLNGE) (acetate) and cyclic Ac-Gly-Leu-Hyp-Gly-Glu (cyclic GLOGE) (acetate), *p<0.05. Assessed by t-test. Data are presented as mean ± SEM. [Diagram 5] Prevention of breast cancer growth by cyclic GLQGE in the form of its hydrochloride salt (cyclic GLQGE HCl salt). Cells of the breast cancer cell line MDA-MB-231 were injected intra-tibialy into mice. Starting on day 30, mice were injected subcutaneously with 0.1 mg / mouse / day of the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE HCl salt) for 10 days or with 0.9% NaCl. On day 40, tumor size was evaluated by bioluminescence imaging (bioluminescence imaging was performed by detecting the photon signal 5 min after D-luciferin injection (150 mg / kg) using an "IVIS Lumina II" imaging system. The resulting images were analyzed using the software "Living Image"). RLU = relative light units. The number of animals in each group was N = 14 / 7 mice in two experiments. *p<0.05 when assessed by t-test. Data are expressed as mean ± SEM. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0113] The following examples are included to demonstrate preferred embodiments of the present invention. Those skilled in the art should understand that the techniques disclosed in the following examples represent techniques that the inventors have confirmed to work well in the practice of the present invention, and therefore can be considered to constitute preferred modes for its practice. However, those skilled in the art should understand in light of this disclosure that many changes can be made in the specific embodiments disclosed and still obtain similar results without departing from the spirit and scope of the present invention. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Thus, this description should be construed as illustrative only and is intended to teach those skilled in the art the general manner of carrying out the invention. It should be understood that the forms of the invention shown and described herein are to be taken as examples of embodiments. It will be apparent to those skilled in the art after having the benefit of this description of the invention that elements and materials can be used interchangeably with those shown and described herein, parts and processes can be reversed, and certain features of the invention can be utilized independently. Changes can be made in the elements described herein without departing from the spirit and scope of the invention, as set forth in the following claims. EXAMPLES

[0114] Example 1: Peptide synthesis The peptide Gly-Leu-Gln-Gly-Glu (GLQGE) was synthesized in the linear form as Gly-Leu-Gln-Gly-Glu-NH2 (also called linear GLQGE-NH2), in the linear form as acetate-Gly-Leu-Gln-Gly-Glu (also called linear Ac-GLQGE), and in the cyclic form as cyclic Gly-Leu-Gln-Gly-Glu (also called cyclic GLQGE without the C-terminal amide and N-terminal acetate). The peptide Pro-Gly-Leu-Gln-Gly-Glu (also called cyclic PGLQGE) was synthesized only in the cyclic form. The control peptides Gly-Leu-Asn-Gly-Glu (also called Linear CT1 (Linear GLGE)) and Gly-Leu-Hyp-Gly-Glu (also called Linear CT2 (Linear GLOGE)) were synthesized in linear form with C-terminal amidation (GLNGE-NH2 and GLOGE-NH2) and N-terminal acetylation (Ac-GLNGE and Ac-GLOGE), and in cyclic form with and without proline (cyclic GLGE or cyclic PGLNGE, and cyclic GLOGE or cyclic PGLOGE). The names of all peptides used in this application are shown in Table 1.

[0115] Linear peptides were synthesized using standard Fmoc (N-(9-fluorenyl)methoxycarbonyl) chemistry on Rink amide resin (Merck KGaA) on an ABI 433 peptide synthesizer (Life Technologies). Peptide purification was by RP-HPLC. Peptide purity and identity were verified by RP-HPLC and ESI-TOF mass spectrometry. Cyclic peptides Gly-Leu-Gln-Gly-Glu were synthesized with Glu directly attached to Gly (head-to-tail cyclization) or with the removal of HO, or in the presence of proline. Cyclic peptides containing proline in the ring were synthesized as fully protected peptides on TCP resin (Intavis Bioanalytical Instruments AG) and cyclized using propylphosphonic anhydride. Cyclic peptides not containing proline were synthesized using solution-phase synthesis. All groups were protected by protecting groups, leaving only the N-terminal amino group and the C-terminal carboxyl group. After ring formation in the solution phase, the protecting groups were removed. In this case, no TCP resin and no propylphosphonic anhydride were used.

[0116] Table 1 shows the peptides used in the present invention and the corresponding SEQ ID NOs in the Sequence Listing.

[0117] [Table 1] TIFF0007629903000026.tif74170

[0118] Linear GLQGE (Gly-Leu-Gln-Gly-Glu)

[0119] [ka]

[0120] Linear Ac-GLQGE (Ac-Gly-Leu-Gln-Gly-Glu)

[0121] [ka]

[0122] Linear GLQGE-NH2 (Gly-Leu-Gln-Gly-Glu-NH2)

[0123] [ka]

[0124] Circular GLQGE

[0125] [ka]

[0126] Circular PGLQGE

[0127] [ka]

[0128] Linear CT1 (Gly-Leu-Asn-Gly-Glu)

[0129] [ka]

[0130] Linear CT1-NH2 (Gly-Leu-Asn-Gly-Glu-NH2)

[0131] [ka]

[0132] Linear Ac-CT1 (Ac-Gly-Leu-Asn-Gly-Glu)

[0133] [ka]

[0134] Cyclic CT1 (Gly-Leu-Asn-Gly-Glu)

[0135] [ka]

[0136] Cyclic CT1+P (Pro-Gly-Leu-Asn-Gly-Glu)

[0137] [ka]

[0138] Linear CT2 (Gly-Leu-Hyp-Gly-Glu)

[0139] [ka]

[0140] Linear CT2-NH2 (Gly-Leu-Hyp-Gly-Glu-NH2)

[0141] [ka]

[0142] Linear Ac-CT2(Ac-Gly-Leu-Hyp-Gly-Glu)

[0143] [ka]

[0144] Cyclic CT2 (Gly-Leu-Hyp-Gly-Glu)

[0145] [ka]

[0146] Cyclic CT2+P (Pro-Gly-Leu-Hyp-Gly-Glu)

[0147] [ka]

[0148] Example 2: Effects of proline-containing cyclic and amidated linear peptides on chemically induced liver fibrosis in mice. To induce liver fibrosis, mice were injected with CCl4 for 6 weeks. Starting on day 32, mice received daily intraperitoneal injections of peptides at a final dose of 25 mg / kg / mouse / day diluted in NaCl 0.9% for a total of 10 days. In these experiments, the following peptides were tested: cyclic peptide Pro-Gly-Leu-Gln-Gly-Glu, cyclic peptide Pro-Gly-Leu-Asn-Gly-Glu, cyclic peptide Pro-Gly-Leu-Hyp-Gly-Glu, linear peptide Gly-Leu-Gln-Gly-Glu-NH2, linear peptide Gly-Leu-Asn-Gly-Glu-NH2, linear peptide Gly-Leu-Hyp-Gly-Glu-NH2.

[0149] The results showed that treatment with CCl4 significantly induced collagen production (a marker of matrix accumulation) in the liver, and the cyclic peptide Pro-Gly-Leu-Gln-Gly-Glu could significantly reduce collagen accumulation. Also, the linear peptide GLQGE-NH2 could significantly reduce the collagen accumulation induced by CCl4. In contrast, neither the cyclic forms of the control peptides (containing Pro: Pro-Gly-Leu-Asn-Gly-Glu or Pro-Gly-Leu-Hyp-Gly-Glu) nor the linear forms of the control peptides Gly-Leu-Asn-Gly-Glu-NH2 and Gly-Leu-Hyp-Gly-Glu-NH2 could reduce the amount of collagen in the liver. Thus, both the linear and cyclic peptides of the sequence Gly-Leu-Gln-Gly-Glu could inhibit the excessive accumulation of extracellular matrix, which may help prevent the progression of fibrosis (Figure 1).

[0150] Example 3: Effect of cyclic peptides (without proline) and acetylated linear peptides on chemically induced liver fibrosis in mice. To induce liver fibrosis, mice were injected with CCl4 for 6 weeks. Starting on day 32, mice received daily intraperitoneal injections of peptides at a final dose of 25 mg / kg / mouse / day diluted in NaCl 0.9% for a total of 10 days. In these experiments, the following peptides were tested: cyclic peptide Gly-Leu-Gln-Gly-Glu, cyclic peptide Gly-Leu-Asn-Gly-Glu, cyclic peptide Gly-Leu-Hyp-Gly-Glu, linear peptide Ac-Gly-Leu-Gln-Gly-Glu, linear peptide Ac-Gly-Leu-Asn-Gly-Glu, linear peptide Ac-Gly-Leu-Hyp-Gly-Glu.

[0151] The results showed that treatment with CCl4 significantly induced collagen production (a marker of matrix accumulation) in the liver, and the cyclic peptide Gly-Leu-Gln-Gly-Glu could significantly reduce collagen accumulation. Also, the linear peptide Ac-Gly-Leu-Gln-Gly-Glu could significantly reduce the collagen accumulation induced by CCl4. In contrast, neither the cyclic nor linear forms of the peptides Ac-Gly-Leu-Asn-Gly-Glu and Ac-Gly-Leu-Hyp-Gly-Glu could reduce the amount of collagen in the liver. Thus, both linear and cyclic forms of the peptide of the sequence Gly-Leu-Gln-Gly-Glu could inhibit the excessive accumulation of extracellular matrix and may help prevent the progression of fibrosis.

[0152] Furthermore, the cyclic peptide Gly-Leu-Gln-Gly-Glu was more efficient in reducing collagen accumulation compared to the proline-containing cyclic peptide Pro-Gly-Leu-Gln-Gly-Glu (compare the Y-axis values ​​in Figures 1 and 2, the difference is statistically significant, p<0.001).

[0153] Example 4: Effect of the hydrochloride salt of the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) on cancer in mice. The cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) in the form of its hydrochloride salt was tested for its ability to prevent cancer growth in a murine melanoma model. B16 melanoma cancer cells (10 6Mice were subcutaneously injected with 1 mg of cyclic GLQGE peptide or 0.9% NaCl (control mice) on day 7. On day 12, mice were euthanized, tumors were removed, and body weight was measured. N=11 / 11 mice. Results are shown in Figure 3 as mean ± SEM. Analysis of tumor weight in control and treated mice showed that the cyclic peptide Gly-Leu-Gln-Gly-Glu (HCl salt) could significantly reduce the cancer size by about 72% compared to control mice. Thus, the cyclic peptide Gly-Leu-Gln-Gly-Glu is a promising therapeutic agent for use in the treatment of cancer.

[0154] Example 5: Effect of the acetate form of the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) on chemically induced pulmonary fibrosis in mice. The cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE acetate) was tested for its ability to prevent pulmonary fibrosis in mice. Pulmonary fibrosis was induced in 6-week-old male C57bl / 6 mice using intratracheal bleomycin instillation at a dose of 0.005 units in 50 μl of 0.9% NaCl on day 0. Starting on day 11, mice were injected subcutaneously with cyclic Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) or control cyclic Ac-Gly-Leu-Asn-Gly-Glu (cyclic GLNGE) or control cyclic Gly-Hyp-Asn-Gly-Glu (cyclic GLQGE) (all three in acetate form) at a dose of 1 mg / mouse / day for 10 days. The results showed that administration of cyclic Gly-Leu-Gln-Gly-Glu (acetate) significantly reduced the total amount of collagen in the lungs compared to mice that received bleomycin only (p<0.05) or the control peptides cyclic Gly-Leu-Asn-Gly-Glu (cyclic GLGEG acetate) or cyclic Gly-Hyp-Asn-Gly-Glu (cyclic GLGEG acetate) (Figure 4).

[0155] Example 6: Effect of the cyclic peptide Gly-Leu-Gln-Gly-Glu (HCl salt) on a mouse breast cancer model. The hydrochloride salt of the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE) was tested for its ability to prevent breast cancer in mice. Metastatic breast cancer bone lesions were induced by injecting cells of the breast cancer cell line MDA-MB-231 into the tibia of CD1 nude mice. Starting on day 30, subcutaneous injections of 0.1 mg of the cyclic peptide Gly-Leu-Gln-Gly-Glu (cyclic GLQGE HCl salt) or 0.9% NaCl were administered daily for 10 days. On day 40, tumor size was evaluated by bioluminescence imaging (bioluminescence imaging was performed by detecting the photon signal 5 min after D-luciferin injection (150 mg / kg) using an "IVIS Lumina II" imaging system. The resulting images were analyzed using the software "Living Image"). The number of animals in the control and treatment groups was N=14 / 7 mice in two experiments. The results showed that administration of cyclic Gly-Leu-Gln-Gly-Glu (HCl salt) significantly (p<0.05) reduced tumor size compared to mice receiving 0.9% NaCl (Figure 5).

Claims

1. A peptide consisting of an amino acid sequence selected from SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5 and SEQ ID NO:6, or a pharma- ceutically acceptable salt thereof.

2. The peptide described in claim 1, wherein the amino acid sequence is SEQ ID NO: 3 or SEQ ID NO:

4.

3. The amino acid sequence is SEQ ID NO:5 【Chemistry 1】 2. The peptide of claim 1.

4. The amino acid sequence is SEQ ID NO:6 【Chemistry 2】 The peptide described in claim 1.

5. A pharmaceutical composition comprising the peptide of claim 1, or a pharma- ceutically acceptable salt thereof, together with at least one selected from the group consisting of pharma- ceutically acceptable vehicles, excipients and diluents.

6. The pharmaceutical composition described in claim 5, wherein the peptide has the amino acid sequence of SEQ ID NO: 3 or SEQ ID NO:

4.

7. The peptide 【Chemistry 3】 The pharmaceutical composition according to claim 5 ,

8. The peptide 【Chemistry 4】 The pharmaceutical composition according to claim 5 ,

9. A peptide according to any one of claims 1 to 4 for use in the treatment of a fibrotic condition characterised by excessive accumulation of extracellular matrix in tissues and / or organs.

10. 10. The peptide for use according to claim 9, wherein the fibrotic condition is selected from the group consisting of liver fibrosis, liver cirrhosis, pulmonary fibrosis, chronic respiratory failure, myocardial fibrosis, ischemic heart disease, heart failure, diabetic nephropathy, glomerulonephritis, myelofibrosis, breast cancer, uterine cancer, prostate cancer, pancreatic cancer, colon cancer, skin cancer, blood cell cancer, cancer of the central nervous system, uterine fibroids, fibromas, fibroadenomas and fibrosarcomas.

11. 11. The peptide for use according to claim 9 or 10, wherein the peptide has the amino acid sequence of SEQ ID NO:3 or SEQ ID NO:

4.

12. The peptide is 【Chemistry 5】 11. The peptide for use according to claim 9 or 10,

13. The peptide 【Chemistry 6】 11. The peptide for use according to claim 9 or 10,

Images