NEW COMBINATION OF ANTI-MADCAM ANTIBODY AND ANTIFIBROTIC CASPASE INHIBITOR TO TREAT LIVER FIBROSIS The invention relates to a new combination of an anti-MAdCAM antibody with an anti-fibrotic agent, such as a protease Inhibitor, preferably a caspase Inhibitor. The invention also relates to pharmaceutical compositions comprising the combination of the invention, and the use of the combination for the treatment of liver fibrosis. Chronic liver disease is responsible for over 1.4m deaths annually (WHO, World Health Report 2004) and in the US is among the top ten disease related causes of death (CDC, National Center for Health Statistics, 2004). Liver fibrosis, which is an outcome of persistent hepatic inflammation, if left unmanaged has serious long-term consequences for patient morbidity and mortality. Liver fibrosis is one of the processes that occurs when the liver is damaged. Such damage may be the result of, for example, viral activity (e.g., chronic hepatitis types B or C) or other liver Infections (e.g., parasites, bacteria); chemicals (e.g., Pharmaceuticals, recreational drugs, excessive alcohol, exposure to pollutants); immune processes (e.g., autoimmune hepatitis); metabolic disorders (e.g., lipid, glycogen, or metal storage disorders); or cancer growth (primary or secondary liver cancer). Fibrosis is both a sign of liver damage and a potential contributor to liver failure via progressive cirrhosis of the liver. There is a serious unmet medical need.-The present invention relate to a combination of art anti-mucosal addressin cell adhesion molecule (MAdCAM) antibody with an anti-fibrotic agent, preferably a protease inhibitor, more preferably a caspase inhibitor, which is beneficial for the treatment of liver fibrosis. Mucosal addressin cell adhesion molecule (MAdCAM) is a member of the immunoglobulin superfamily of cell adhesion receptors. It is one of the adhesion molecules involved in the recruitment of lymphocytes to tissues when required, by means of interacting with an integrin molecule on the surface of the lymphocytes. It has been shown that antibodies that inhibit binding of WIAdCAM to its integrfn binding partner, oup?, for example anti-MAdCAM antibodies (e.g. MECA-367; US 5,403,919, US 5,638,724) oranti-ouP? antibodies (e.g. Act-1; US 6,551,593), can inhibit leukocyte extravasation into inflamed intestine, and can therefore be beneficial In the treatment of inflammatory bowel disease (IBD). Aspects of the invention One aspect of the invention is a combination of an anti-MAdCAM antibody or antigen-binding portion thereof with an anti-fibrotic agent. Preferably, the anti-fibrotic agent is a protease Inhibitor, more preferably a caspase inhibitor, even more preferably the caspase inhibitor is a compound of formula I: The compound of formula I (Formula Removed) wherein A, B, R1 and R2 are as defined below. Preferably, the compound of formula I is selected from: (3S)-3-[N-(N'-(2-Fluoro-4-lodophenyl}Oxamyl)Valinyl]Amino-5-(2 3',5',6l-Tetrafiuorophenoxy}-4- Oxopentanoic acid; {3S)-3-{N-(Nl-(2-Chlorophenyl)Oxamyl}Valinyl]Amino-5-(2',31,5',61-Tetrafluorophenoxy)-4-Oxopentano,3',5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(Nl-(2,6-Difluorophenyl)Oxamy!)Alaninyl]Amir»o-5-(2113',5',6'-Tetrafluorophenoxy}-4- Oxopentanoic acid; (3S)-3-(1-Naphthyl)Oxamyl)AIaninyljArninc-5-(2,3,5,6-Tetrafluorophenoxy^Oxopentanoicacid; (3S)-3-[N-(N1-(4-Methoxyphenyl)Oxamyl)Alaninyl]Aminc-5-(2',31,5',6'-Tetrafiuorophenoxy)-4- Oxopentanoic acid; (3S)-3-N-(N'-(2-Trifluoromethylphenyl)Oxamyl}Valinyl]Amino-4-Oxobutanoicacid; (3S)-3-[N-(N'-(2-tert-Butylmathylphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoic acid; (3S)-3-[N-{N'-(2-Benzylphenyl)Oxamyl}Valinyl]Amino-4-Oxobutanoicacid; (3S)-3-[N-(N'-(2-Phenylphenyl}Oxamyl)Valinyl]Amino-4-Oxobutanoicacid. Even more preferably, the compound is (3S)-3-[N-(N'-(2-Tert-Butylphenyl)Oxamyl)Alan!nyl}Amino-5-(2J,3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid. In one aspect of the invention the anti-MAdCAM antibody or antigen-binding portion thereof in the combination is an antibody or antigen-binding portion thereof that specifically binds MAdCAM. Preferably, the antibody or portion is a human monoclonal antibody or antigen-binding portion thereof. Preferably, the antibody or portion possesses at least one of the following properties: (a) binds to human cells; (b) has a selectivity for MAdCAM over VCAM or fibronectin of at least 100 fold; (c) binds to human MAdCAM with a Kd of 3 x 10-10 M or less; or (d) inhibits the binding of α4β7 expressing cetls to human MAdCAM. (e) inhibits the recruitment of lymphocytes to gastrointestinal lymphoid tissue. Preferably, the antibody or antigen-binding portion inhibits binding of human MAdCAM to a4BTl and has at least one of the following properties: (a) cross-competes with a reference antibody for binding to MAdCAM; (b) competes with a reference antibody for binding to MAdCAM; (c) binds to the same epitope of MAdCAM as a reference antibody; (d) binds to MAdCAM with substantially the same Kd as a reference antibody; (e) binds to MAdCAM with substantially the same off rate as a reference antibody; wherein the reference antibody is selected from ttie group consisting of: monoclonal antibody 1.7.2, monoclonal antibody 1.8.2, monoclonal antibody 6.14.2, monoclonal antibody 6.22.2, monoclonal antibody 6.34.2, monoclonal antibody 6.67.1, monoclonal antibody 6.73.2, monoclonal antibody 6.77.1, monoclonal antibody 7.16.6, monoclonal antibody 7.20.5, monoclonal antibody 7.26.4, monoclonal antibody 9.8.2, monoclonal antibody 6.22,2-mod, monoclonal antibody 6.34.2-rnod, monoclonal antibody 6.67.1-mod, monoclonal antibody 6.77.1-mod and monoclonal antibody 7.26.4-mod. In another aspect of the invention the heavy chain variable region, the light chain variable region or both of the anti-MAdCAM antibody are at least 90% identical in amino acid sequence to the corresponding region or regions of a monoclonal antibody selected from the group consisting of: monoclonal antibody 1.7.2, monoclonal antibody 1.8.2, monoclonal antibody 6.14.2, monoclonal antibody 6.22.2, monoclonal antibody 6.34.2, monoclonal antibody 6.67.1, monoclonal antibody 6.73.2, monoclonal antibody 6.77.1, monoclonal antibody 7.16.6, monoclonal antibody 7.20.5, monoclonal antibody 7.26.4 monoclonal antibody 9.8.2, monoclonal antibody 6.22.2-mod, monoclonal antibody 6.34.2-mod, monoclonal antibody 6.67.1-mod, monoclonal antibody 6.77.1-mod and monoclonal antibody 7.26.4-mod, Preferably the antibody is selected from the group consisting of. (a) an antibody comprising the amlno acid sequences set forth in SEQ ID NO: 2 and SEQ ID NO: 4, without the signal sequences; (b) an antibody comprising the amino acid sequences set forth in SEQ !D NO: 6 and SEQ ID NO: 8, without the signal sequences; (c) an antibody comprising the amlno acid sequences set forth in SEQ ID NO: 10 and SEQ ID NO: 12, without the signal sequences; (d) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 14 and SEQ ID NO: 16, without the signal sequences; (e) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 18 and SEQ ID NO: 20, without the signal sequences; (f) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 22 and SEQ ID NO: 24, without the signal sequences; (g) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 26 and SEQ ID NO: 28, without the signal sequences; (h) an antibody comprising the amino acid sequences set forth in SEQ !D NO: 30 and SEQ ID NO: 32, without the signal sequences; (i) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 34 and SEQ ID NO: 36, without the signal sequences; 0) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 38 and SEQ ID NO: 40, without the signal sequences; (k) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 42 and SEQ ID NO: 44, without the signal sequences; (I) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 46 and SEQ ID NO: 48, without the signal sequences; (m) an antibody comprising the amino acid sequences set forth In SEQ ID MO: 52 and SEQ ID NO: 54, without the signal sequences; (n) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 56 and SEQ ID NO: 58, without the signal sequences; (o) an antibody comprising the amino add sequences set forth in SEQ ID NO: 60 and SEQ ID NO: 62, without the signal sequences; (p) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 64 and SEQ ID NO: 66, without the signal sequences; and (q) an antibody comprising the amino acid sequences set forth in SEQ ID NO: 42 and SEQ ID NO: 68, without the signal sequences. In one aspect of the invention, the heavy chain C-terminal lysine may be cleaved from the anti-MAdCAM antibody of the combination. In another aspect of the invention, the monoclonal antibody or an antigen-binding portion thereof is selected from the following antibodies: (a) the heavy chain comprises the heavy chain CDR1, CDR2 and CDR3 amino acid sequences of a reference antibody selected from the group consisting of: 1.7.2, 1.8.2, 6.14.2, 6.22.2, 6.34.2, 6.67.1, 6.73.2, 6.77.1, 7.16.6, 7.20.5, 7.26.4, 9.8.2, 6.22.2-mod, 6.34.2-mod, 6.67.1-motJ, 6.77.1-mod and 7.26.4- mod (b) the light chain comprises the light chain CDR1, CDR2 and CDR3 amino acid sequences of a reference antibody selected from the group consisting of: f.7.2, 1.8.2, 6.14.2, 6.22.2, 6.34.2, 6.67.1, 6.73.2, 6.77.1, 7.16.6, 7.20.5, 7.26.4, 9.8.2, 6.22.2-mod, 6.34.2-mod, 6.67.1-mod, 6.77.1-mod and 7.26.4- mod (c) the antibody comprises a heavy chain of {a} and a light chain of (b); and (d) the antibody of (c) wherein the heavy chain and light chain CDR amino acid sequences are selected from the same reference antibody. In another aspect of the invention, the monoclonal antibody or antigen-binding portion comprises: (a) a heavy chain comprising the heavy chain variable region amino acid sequence of an antibody selected 1rom the group consisting of: 1.7.2 (SEQ ID NO: 2); 1.8.2 (SEQ ID NO: 6}; 6.14.2 (SEQ ID NO: 10); 6,22.2 (SEQ ID NO: 14); 6,34.2 (SEQ ID NO:'18); 6.67.1 (SEQ ID NO: 22); 6.73.2 {SEQ ID NO: 26); 6.77.1 (SEQ ID NO: 30); 7.16.6 (SEQ ID NO: 34); 7.20.5 (SEQ ID NO: 38); 7.26.4 (SEQ ID NO: 42); and 9.8.2 (SEQ ID NO: 46); 6.22.2-mod (SEQ ID NO; 52); 6.34.2-mod (SEQ ID NO: 56); 6,67.1 -mod (SEQ ID NO: 60); 6,77.1-mod (SEQ ID NO: 64); and 7.26.4-mod (SEQ ID NO: 42); (b) a light chain comprising the light chain variable region amino acid sequence of an antibody selected from the group consisting of: 1.7.2 {SEQ ID NO: 4); 1.8.2 (SEQ ID NO: 8); 6.14.2 (SEQ ID NO: 12); 6.22.2 (SEQ ID NO: 16); 6.34.2 (SEQ ID NO: 20); 6,67.1 (SEQ ID NO: 24); 6.73.2 (SEQ ID NO: 28); 6.77.1 (SEQ ID NO: 32); 7.16.6 (SEQ ID NO: 36); 7.20.5 (SEQ ID NO: 40); 7.26.4 (SEQ ID NO: 44); and 9.8.2 (SEQ ID NO: 4B); 6.22.2-mod (SEQ ID NO: 54); 6.34.2-mad (SEQ ID NO: SB); 6.67.1 -rood (SEQ ID NO: 62); 6.77.1-mod (SEQ ID NO; 66); and 7.26.4-mod (SEQ ID NO: 68); or (c) the heavy chain of (a) and the light chain of (b). Yet another aspect of the Invention is a combination of an anti-α4β7 integrin antibody or antigen binding portion thereof with a caspase inhibitor as defined herein. Preferably, the antibodyinhibite the interaction of MAdCAM with α4β7 integrin. More preferably, the antibody is humanised Act-1, also called MLN02 (WO 01/078779). Another aspect of the invention is the medical use of any combination described herein, preferably the use for the treatment of liver fibrosls, including but not limited to, the treatment of Hepatitis C-induced liver damage, alcoholic liver disease, non-alcoholic steatohepatitis (NASH). Another aspect of the invention is a method of treatment of liver fibrosis including but not limited to, the treatment of Hepatitis C-induced liver damage, alcoholic liver diseaee, non-alcoholic steatohepatMs (NASH), using an anti-MAdCAM antibody as described herein and an anti-fibrotic agent as described herein. Another aspect of the invention is a pharmaceutical composition comprising any combination described herein with a pharmaceutically acceptable carrier or excipient Another aspect of the invention is a pharmaceutical product comprising an anti-MAdCAM antibody as described herein and an antl-fibrotic agent as described herein for simultaneous, separate, or sequential use. A further aspect of the invention is a kit comprising an anti-MAdCAM antibody as described herein and an anti-fibrotic agent as described herein. Detailed description of the invention The anti-fibrotlc agent in combination of the invention is preferably a protease inhibitor, more preferably a caspase inhibitor, and even more preferably a compound of formula I (Formula Removed) wherein A Is a natural or unnatural amino acid of Formula lla- (Formula Removed) B is a hydrogen atom, a deuterium atom, alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, substituted naphthyl, 2-benzoxeszolyl, substituted 2-oxazolyl, (CH2)n-cyc!Dalkyl, (CH2)n-phenyJ, (CH2)n-(substituted phenyl), (CH2)n-(1 or 2-naphthyl), (CH2)n-(substituted 1 or 2-naphtrtyl), (CHE)n-(heteroaryl), (CH2)n-(substituted heteroaryl), halomethyl, CO2R12, CONR13R14, CH2ZR15, CH2OCO(aryl), CH2OCO(heteroaryl), or CH2OPO(R16)R17, where Z is an oxygen or a sulfur atom, or B is a group of the Formula Illa-c: (Formula Removed) R1 is alkyl, cycloalkyl, (cycloalkyl)alkyl, phenyl, substituted phenyl, phenylalkyt, substituted phenylalkyi, naphthyl, substituted naphthyl, (1 or 2 naphthyl)alky1, substituted (1 or 2 naphthyl)alkyl, heteroaryl, substituted heteroaryl, (heteroaryl)alkyl, substituted {heteroaryljaikyl, R1a{R1b)M, or R1°0; and R2 is hydrogen, lower alkyl, cycloalkyl, (cycloalkyl)alkyl, phenyl, substituted phenyl, phenylalkyi, substituted phenylalkyi, naphthyl, substituted naphthyl, (1 or 2 naphthytyalkyS, or substituted {1 or 2 naphthyl)alkyl; And wherein: R1a and R1b are independently hydrogen, alkyl, cycloalkyl, (cycloalkyl) alky I, phenyl, substituted phenyl, phenylalkyl, substituted phenylalkyi, naphthyl, substituted naphthyl, (1 or 2 naphthyl)alkyl, substituted (1 or 2 naphthyl)alkyl, heteroaryl, substituted heteroaryl, (heteroaryl)alkyl, or substituted (heteroaryl)alkyl, with the proviso that R1a and R1b cannot both be hydrogen; R1° is alkyl, cycloalkyi, (cycloalkyl)alkyl, phenyl, substituted phenyl, phenyfalkyl, substituted phenylalkyi, naphthyl, substituted naphthyl, (1 or 2 naphthyl)alkyl, substituted (1 or 2 naphthyl}a!kyl, heteroaryl, substituted heteroaryl, (heteroaryl)alkyl, or substituted (heteroaryl)alkyl; R3 is C^ alkyl, cycloalkyl, phenyl, substituted phenyl, (CH2)nNH2, (CH2)NHCOR3, {CH2)nN(C=NH)NH2, (CH2UC02R2, (CH2)mOR10, (CH2)mSR11, (CH2)ncycloalkyl, (CH2)nphenyl,(CHa}n(substituted phenyl), (CH2)n(1 or 2-naphthyl) or (CH2)n(heteroaryl), wherein heteroaryi includes pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyi, isoxazolyl, pyrazinyl, pyrimidyl, trlazinyl, tetrazolyl, and Indolyl; R3" is hydrogen or methyl, or R3 and R3a taken together are -(CH2)d- where d is an integer from 2 to 6; R4 is phenyl, substituted phenyl, (CH2)phenyl, (CH2)m{substituted phenyl), cycloalkyl, or benzofused cycloalkyl; R5 is hydrogen, lower alkyl, cycloalkyl, phenyl, substituted phenyl, (CH2)ncycloa!kyt, (CH2}nphenyl,,- (CH2)n(substituted phenyl), or(CH2)n(1 or 2-naphthyl); R6 is hydrogen, fluorine, oxo, lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, (CH2)ncycloalkyl, (CH2)nphenyl, (CH2)n(substituted phenyl), (CH2)n(1 or 2-naphthyl), OR10, SR11, or NHCOR9; R7 is hydrogen, oxo (i.e. =O), lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, (CH2)ncycloalkyl, (CH2)nphenyl, (CH2)n(substituted phenyl), or(CH2)n(1 or 2-naphthyl); RB is lower alkyl, cycloalkyl, (CH2)ncycloalkyl, (CH2)nphenyl, (CH2)n(substituted phenyl), (CH2)n(1 or 2- naphthyl), or COR9; R9 is hydrogen, lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, (CH2)ncycloa!kyl, (CH2)nphenyl, (CH2)n(substituted phenyl), (C1H2)n(1 or 2-naphthyl), OR12, or NR13RH; R10 is hydrogen, lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, (CH^cycloalky?, (CH2)0phenyl, (CH2)n{substituted phenyl), or(CH2)n{1 or 2-naphthyl); R1' \s lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, (CH2)ncycloalkyt, (CH2)nphenyl, (CHz)n{subslltuted phenyl), or(CH2)n(1 or 2-naphthyl); R12 is lower alkyl, cycloalkyl, (CH2)ncycloalkyl, (CH2)nphenyl, (CH2)n(substituted phenyl), or (CHz)n(1 or 2- naphlhyl); R13 is hydrogen, lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, substituted naphthyl, (CH2)ncycloa)kyl, (CH2)nphenyl, (CH2)nsubsWuted phenyl), or (CH2)n(1 or 2-naphthyl)', RM Is hydrogen or lower alkyl; or R13 and Rw taken together form a five to seven membered carbocyclic or heterocyclic ring, such as morpholine, or N-substituted plperazine; R15 is phenyl, substituted phenyl, naphthyl, substituted naphihyl, heteroaryl, (CH2)nphenyl, (CH2)n(substituted phenyl), (CH2)n{1 or 2-naphthyl), or (CH2)n(heteroaryl); R16 or R17 are Independently lower alkyl, cycloalkyl, phenyl, substituted phenyl, naphthyl, phenylalkyl, substituted phenylalkyl, or (cycloalkyl)alkyl; R18 and R18 are independently hydrogen, alkyl, phenyl, substituted phenyl, (CHa)nphenyl, (CHsUsubstituted phenyl), or Ru and R18 taken together are -(CH=CH)r; R20is hydrogen, alkyl, phenyl, substituted phenyl, (CH2)nphenyl, {CH2)n(substituted phenyl); R21, R72 and R23 are independently hydrogen, or alkyl; X is CH2, (CH2)2, (CH2)3, or S; Y1 is 0 or NR23; Y2isCH2, O.orNR23; a is 0 or 1 and b is 1 or 2, provided that when a is 1 then b is 1; c is 1 or 2, provided that when c is 1 then a is 0 and b is 1; m is 1 or 2; and nis 1, 2, 3, or 4; or a pharmaceutically acceptable salt thereof. As used herein, the term "alkyl" means a straight or branched C1to C10 carbon chain, such as methyl, ethyl, tert-butyl, iso-propyt, n-octyl, and the like. The term "lower alkyl" means a straight chain or branched C1to C6 carbon chain, such as methyl, ethyt, iso-propyl, and the like. The term "cycloalkyl" means a mono-, bi-, or tricyclic ring that is either fully saturated or partially unsaturated. Examples of such a ring include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, cyclooctyl, cis or trans decalln, blcyclo[2.2.1thept-2-ene, cyclohex-1-enyl, cyclopent-1-enyl, 1,4-cyclooctadienyl, and the like. The term "(cycloalkyl)alkyf' means the above-defined alkyl group substituted with one fo the above cycloalkyl rings. Examples of such a group include (cyclohexyl)methyl, 3-(cyc)opropyl)-n-propyi, 5-(cyclopentyl)hexyl, 6-adamantyl)hexyl, and the like. The term "substituted phenyl" specifies a phsnyl group substituted with one or more substituents chosen from halogen, hydroxy, protected hydroxy, cyano, nitro, trifluoromethyl. alkyl, allcoxy, acyl, acyioxy, carboxy, protected carboxy, carboxymethyl, protected carboxymethyl, hydroxymethyl, protected hydroxymethyl, amino, protected amlno, (monosubstltutec()amino, protected (monosubstituted}aminor (disubstituted)amino, carboxamide, protected carboxamide, N-(lower alkyl)carboxamide, N-((tower a!kyl)sutfonyt)amino, N-(phenylsulfonyl)amino or by a substituted or unsubstituted phenyl group, such that in the latter case a biphenyl or naphthyl group results, or wherein two adjacent alkyl substituents on the substituted phenyl ring taken together form a cycloalkyl to yield, for example, tetrahydronaphthyl or indanyi. Examples of the term "substituted phenyl" includes a mono-, di-, tri-, tetra, or penta{halo}phenyl group such as 2-, 3-, or 4-chlorophenyl, 2,6-dichlorophenyl, 2,5-drchlorophenyl, 3,4-d)ch!orophenyl, 2,3-or 4-bromophenyl, 3,4-dibromophenyl, 3-chloro-4-tluorophenyl, 2-, 3- or 4-fluoraphenyi, 2,4,6-tfifluorophenyl, 2,3,5,6-tetrefluorophenyl, 2,3,4,5-tetrafluorophenyl, 2,3,4,5,6-pentafluorophenyl, and the like; a mono or di(hydroxy)pheny! group such as 2-, 3-, or 4-hydroxyphenyl, 2,4-dihydroxyphenyl, the protected hydroxy derivatives thereof and the like; a nitrophenyl group such as 2-, 3-, or 4-nitrophenyl; a cyanophenyl group, for example, 2-, 3-, or4-cyanophenyl; a mono or di(alkyl)phenyl group such as 2-, 3-, or 4-ethylphenyl, 2-, 3-, or 4-(n-propyl)phenyl and the like; a mono or di(alkoxy)phenyl group, for example, 2,6-dimethoxyphenyl, 2-, 3-, or 4-(iso-propoxy)phenyl, 2-, 3-, or 4-{t-butoxy)phenyl, 3-ethoxy-4-methoxyphenyl and the like; 2-, 3-, or 4-(pratected hydroxymethyl)phenyl or 3,4-di{hydroxymethyl)phenyl; a mono- or di(aminomethyl)phenyl or (protected aminomethyl)phenyt such as 2-, 3- or 4-(aminomethyl)phenyl or 2,4-(protected aminomethyl)phenyl; or.a mono- or di(N-(methylsulfonylamlno))pheny! such as 2-, 3-, or4-(N-(methylsulfonylamino))phenyf. Also the term "substituted phenyl" represents disubstituted phenyl groups wherein the substituents are different, for example, 3-methyl~4-hydroxyphenyl, 3-hydroxy-4-nitrophenyl, 2-hydroxy-4-chforopheny1, and the like. The term "phenylalkyl" means one of the above phenyl groups attached to one of the above-decribed alkyl groups, and the term "substituted phenylalkyP means that either the phenyf or the alkyl or both are substituted with one or more of the above-defined substituents. Examples of such groups include 2-phenyl-1-chloroethyl, 2-(4'-methoxyphenyl)ethyl, 4-{2'6'-dihydroxy phenyl)n-hexyl, 2-(5'cyano-3'- • methoxyphenyOn-pentyl,3(2,6-dimethylphenyOn-propyl, 4-chloro-3-aminobenzyl, 6-(4'-methoxyphenyl)-3-carboxy(n-hexyl), 5-(4'-aminomethylphenyl)-3-(aminomethyl)n-pentyl, 5-phenyl-3-oxo-n-pent-1-yl, (4-hydroxynaph-2-yl)rnethyl, and the like. The term "substituted naphthyl" means a naphthyl group substituted with one or more of the above-identified substituents, and the term "(1 or 2 naphthyl)alkyl" means a naphthyl (1 or 2) attached to one of the above-described alkyl groups. The terms "halo" and "halogen" refer to the fluoro, chloro, bromo or iodo groups. These terms may also be used to describe one or more halogens, which are the same or different. Preferred halogens in the context of this invention are chloro and fluoro. The term "aryl" refers to aromatic five and six membered carbocyclic rings. Six-membered rings are preferred. The term "heteroary!" refers to optionally substituted aromatic five-membered or six-membered heterocyclic rings that have 1 to 4 heteroatoms, such as oxygen, sulfur and/or nitrogen atoms, in particular nitrogen, either alone or in conjunction with sulfur or oxygen ring atoms. The following ring systems are representative examples of the heterocyclic radicals denoted by the term "heteroaryl" (whether substituted or unsubstituted): iheinyl, furyl, pyrrolyl, p/rrolidinyl, imicfazolyl, isoxazolyl, trlazolyl, thladlazolyl, gxadiazolyl, tetrazolyl, thlatrlazolyl, oxatrlazolyl, pyridyl, pyrimidyl, pyrazinyl, pyridazinyl, oxazinyl, triazinyl, thiadiazinyl, tetrazolo, 1,5-[b]pyridaziny! and purinyl, as well as benzo-fused derivatives, for example, benzoxazolyl, benzothiazolyl, benzimidazolyl and indolyl. Substituents for the above optionally substituted heterosryl rings are from one to three hato, trihalomethyl, amino, protected amlno, amino salts, mono-substituted amino, di-substituted amino, carboxy, protected carboxy, carboxylate salts, hydroxy, protected hydroxy, salts of a hydroxy group, lower alkoxy, lower alkylthio, lower alkyl, substituted lower alkyl, cycloalkyl, substituted cycloalky), (cycloalkyl)alkyl, substituted (cycloalkyl)alkyl, pheny), substituted phenyl, phenylalkyl, and substituted phenylalkyl groups. Substituents for the heteroaryl group are as defined above, or as set forth below. As used In conjunction with the above Substituents for heteroaryl rings, "trihalomethyl" can be trifluoromethyl, trichlorornethyl, tribromomethyl or triiodomethyl; "lower alkoxy means a C1 to C4 alkoxy group, similarly, "lower alkylthio" means a CM to C4 alkylthio group. The term "substituted lower alkyl" means the above-defined lower alkyl group substituted from one to three times by a hydroxy, protected hydroxy, amino, protected amino, cyano, halo, trifluoromethyl, mono-substituted amino, di-substituted amino, lower aikaxy, lower alkylthio, carboxy, protected carboxy, or a carboxy, amino, and/or hydroxy salt. As used in conjunction with the Substituents for the heteroaryl rings, the terms "substituted (cycloalkyl)alkyl" and "substituted cycloalkyl" are as defined above substituted with the same groups as listed for a "substituted alkyl" group. The term "(monosubstituted)amino" refers to an amino group with one substituent chosen from the group consisting of phenyl, substituted phenyl, a!kyl, substituted alkyl, C, to C7 acyl, C2 to C7 alkenyl, C2 to C7 substituted alkenyl, C2 to C7 alkynyl, C7 to C16 alkylaryl, C7 to C1B substituted alkylaryl and heteroaryl group. The (monosufostituted)amino can additionally have an amino-protecting group as encompassed by the term "protected (monosubstituted)amino". The term "(disubstituted)amino" refers to amino groups with two Substituents chosen from the group consisting of phenyl, substituted phenyl, alkyl, substituted alkyl, C1 to C7 acyl, C2 to C7 alkenyl, C2 to C7 alkynyl, C7 to C16 substituted alkylaryl and heteroaryl. The two Substituents can be the same or different. The term "heteroaryl(alkyl)" denotes an alkyl group as defined above, substituted at any position by a heteroaryl group, as above defined. Furthermore, the above optionally substituted flve-membered or six-membered heterocyclic rings, and the above cycloalkyl rings, can optionally be fused to an aromatic five-membered or six-membered ring system such as a pyridine or a triazole system, and preferably to a benzene ring. The term "carboxy-protecting group" as used herein refers to one of the ester derivatives of the carboxylic acid group commonly employed to block or protect the carboxylic acid group while reactions are carried out on other functional groups on the compound. Examples of such carboxylic acid protecting groups include t-butyl, 4-nitrobenzyl, 4-methoxyfaenzyl, 3,4-dimethoxybenzyl, 2,4-dimelhoxybenzyl, 2,4,6-trimethoxybenzyl, 2,4,6-trimethylbenzyl, pentamethylbenzyl, 3,4-methylenediaxybenzyl, benztiydryl, 4,4'dimethoxytrityl, 4,4',4"-trimethoxytrityl, 2-phenylpropyl, trimethylsilyl, t-butyldimethylsilyi, phenacyl, 2,2,2-trichloroethyl, p-(trimethylsilyl)ethyl, β-{di(n-butyl)methylsilyl)ethyl, p-toluenes,ulfonylethyl, 4-nitrobenzylsulfonylethyl, allyl, cinnamyl, 1-(trimethylsilylmethyl)-propertyl and like moieties. The species of carboxy-protecting group employed is not critical so long as the derivatked carboxylic acid is stable to the conditions of subsequent reaction(s) and can be removed at the appropriate point without disrupting the remainer of the molecule. The term "hydroxy-protecting group" refers to readily claavable groups bonded to hydroxyl groups, such as the tetrahydropyranyl, 2-methoxyprop-2-yl, 1-ethoxyeth-1-yl, methoxymethyl, p-methoxyethoxymethyl, methylthiomethyl, t-butyl, t-amyl, trityl, 4-methoxytrityl, 4,4'-dimethoxytrityl, 4,4114"-trimethoxytrityl, benzyl, allyl, trimethylsilyl, (t-butyl)dimethylsilyl, 2,2,2-trichloroethoxycarbonyl, and the like. The term "ammo-protecting group" as used herein refers to substituents of the amino group commonly employed to block or protect the amino functionality while reacting other functional groups of the molecule. The term "protected (monosubstituted)amino" means there is an amino-protecting group on the monosubstituted amino nitrogen atom. Examples for such amino prelecting groups are listed in WO 00/01666. The terms "natural and unnatural amino acid" refer to both the naturally occurring amino acids and other non-proteinogenic a-amino acids commonly utilized by those in the peptide chemistry arts when preparing synthetic analogues of naturally occurring peptides, including D and L forms. The naturally occurring amino acids are glycine, alanine, valine, leucine, Isoleuclne, serine, methionine, theonine, phenylalanine, tyrosine, tryptophan, cysteine, proline, hlstldlne, aspartlc acid, asparaglne, glutamic acid, glutamine, y-carboxyglutamic acid, arginine, ornithine and lysine. Examples of unnatural a-amino acids include hydroxylysine, citrulline, kynurenine, (4-aminophenyl)alanine, 3-(2'-naphthyl)alanine, 3-(1'-naphthyl)alanine, methionine sulfone, (t-butyl)alanine, (t-butyl)glycine, 4-hydroxyphenyl-glycine, aminoalanine, phenylglycine, vinylalanine, propargyl-glycine, 1,2,4-triazolo-3-alartine, thyronine, 6-hydroxytryptophan, 5-hydroxytryptophan, 3-hydroxykynurenine, 3-aminotyrosine, trifluoromethylalanine, 2-thlenylalanine, (2-(4-pyridyl)ethyl)cysteine, 3,4-dimethoxy-phenylalanine, 3-{2'-thiazolyl)alanine, ibotenic acid, 1-amino-l-cyclopentane-carboxyiicacid, 1-amino-1-cyclohexanecarboxylicacid, quispualic acid, 3-(trifluoromethylphenyl)alanine, (cyclohexyl)glycine, thiohlstldine, 3-methoxytyrosine, norleucirte, norvaline, alloisoleucine, homoarginine, thioproline, dehydroproline, hydroxyproline, homoproline, indoline-2- carboxyllc acid, 1,2,3,4-tetrahydroisoquinoline-3-carboxyiic acid, 1,2,3,4-tetrariydroquinoline-2-carboxy]ic acid, a-amlno-n-butyric acid, cyclohexylalanlne, 2-amlno-3-phenylbutyric acid, phenylalanine substituted at the ortfio, meta, or para position of the phenyl moiety with one or two of the following groups: a (C, to C4 alkyl, a (C1 to C4)alkoxy, a halogen or a nitro group, or substituted once with a methylenedioxy group; b-2- and 3-thlenylalanine; p-2- and 3-furartylalanine; J3-2-, 3- and 4-pyridylalanine, f}-(benzothienyl-2- and 3-yI)alanine; p-(1- and 2-naphthyl)alanine; 0-alkylated derivatives of serine, threonine or tyrosine; S-alkylated cysteine, S-alkylated homocysteine, the O-sulfate, 0-phosphate, and O-carboxylate esters of tyrosine, 3-(suHb)tyroslne, 3-{carboxy)tyrosine, 3-(phospho)tyrosine, the 4-metharte-sulfonic acid ester of tyrosine, 4-methanephosphonic acid ester of tyrosine, 3,5-diiodotyrosine, 3-n'rtrolyrosine, s-aikyliysine, and 6-alkyl ornithine. Any of these α-amino acids may be substituted with a methyl group at the alpha position, a halogen at any position of the aromatic residue on the cx-amlno side chain, or an appropriate protective group at the O, N, or S atoms of the side chain residues. Appropriate protecting groups are discussed above. Depending on the choice of solvent and other conditions known to the skilled person, these compounds may also take the ketal or acetal form, and the use of these forms in the combination of the invention is included in the invention. These compounds can be prepared as described in WO 00/01666 or in US 6,544,951, hereby incorporated by reference in their entirety Preferred subgroups are those listed in US 6,544,951. A preferred compound of formula I is selected from: (3S)-3-[N-(N'-(2-benzylphenyl)Oxamyl)Valinyl]Amino-5-(2,3,5,6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Valinyl]Amlno-5-(2',3',5,,6,Tetrafluorophenoxy5-4-Oxopentanoicacid; (3S)-3-[N-(N'-(Benzyl)Oxamyl)Valinyl]Amino-5-(2'13,5,,6'-Tetrafluorophenoxy}-4-Oxopen1ano!cacid; (3S)-3-[N-(N'-(2-phenoxyphenyl)Oxamyl)Valinyl]Amino-5-{2',3',5',6>-Tetrafluorophenoxy)-4-Oxopentanoic acid; {3S)-3-[N-(N-l-Naphthylmethyl)Oxamyl)ValinyllAmino-5-(2,3,5,6-TetrafluorophenoxyJ-^-Oxopentanoic acid; {3S)-3-[NKN'-(4-Chloro-1-Naphthyl)Oxarnyl)Valinyl]Amino-5-(2',3',5',6'-TetrafluorophenoxyH- Oxopentanoic acid; (3S)-3-[N-(N'-(2-Anthryl)Oxamyl}Valinyl]Amino-5-(2'13',5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid; (3S)-3-fN-(N'-(Phenethyl)Oxamyl)Valinyl]Amino-5-{2',3',5',6'-Tetrafluoroprienoxy)-4-Oxopentanoicacid; (3S)-3-[N-(N'-(Phenyl)Oxamyl)Vaiinyl]AminD-5-(2',3',5',6'-Tetratluorophenoxy)-4-Oxopenlanoicacid; (3S)-3-[N-(N'-(2-Phenylpheny!)Oxamyl)Valinyl]Amino-5-(2l,3',5',6'-Tetraf)uorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N1-(4-n-Heptylphenyl)Oxamyl)ValinyliAmino-5-{2',3',51,6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; Oxopentanoic acid; (3S}-3-[N-(N'-(1-Adamantyl)Oxamyl)Valinyl]Amino-5-(2',3l,5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid; acid; (3S)-3-[N-(N'-(Z-Naphthyl)Oxaniyl)Valinyl]Amino-5(2,3,5,6-TetraftuorophenoxyJ-^-Oxopentanoicacid; (3S)-3-(N-(N'-(2-methoxyphenyl)Oxamyl)Valinyl]Amfno-5-(2'13,5,6-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[M-(N1-(N''-N'''-Diphenylamoni}Oxamyl)VallnytlAmino-5-(21,3'15',6l-TetrafluorophenoxyHl-Oxopentanoic acid; (3S)-3-[N-(N'-(4-Pyridinyl)Oxamyl}Va!inyl]Amino-5-(21,3',5',61-Tetrafluorophenoxy)-4-Oxopen!anoicacki; (3S)-3-[M-(N'-(1,2,3,4-Tetrahydro-1-Naphthyl)Oxamyl}Valinyl]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; {3S)-3-[N-(N'-(3,415-Trinnethoxybenzyt)Oxamyl)Valinyl]Amino-5-{2113',5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; {3S}-3-[N-{N'-(Benzhydryl)Oxamyl)Valinyl]Amino-5-(2'r3',5',6'-Tetraf(uorophenoxy)-4-Oxopertanoicacid; (3S)-3-[N-(N'-(3-Phenoxylphenyl}Oxamyl)Valmyl]Amino-5-(21,3',5'B'-Tetrafluorophenoxy)-4-Oxopentanoic acid; {3S}-3-[N-(N'-{2-tert-Butylphenyl)Oxamyl)ValinylIAmino-5-(2I,3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-{N'-{2-Pyridinyl)Oxamyl)yalinyl]Amino-5-(2I,3',5'16 -Tetrafluorophenoxy}-4-Oxopen1anoicacid; (3S)-3-(N-(N'-(2,3,5,6-Tetrafluoro-4-Pyridinyl)Oxamyl}Valinyl]Amino-5-(2',3l,5',61-TetranLrorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N1-(2-iodophenyl)Oxamyl)Valinyl]Amino-5-(2',3',5',6'-TetfafluorQphenoxy)-4-Oxopentanoi& acid; (3S)-3-[N-(N1-(2,6-Difluorophenyl)Oxamyl}Valinyl]Amino-5-(2>,31,5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2,5-Di-tert-Butylphenyl)Oxamyl)Valinyl]Amino-5-(2'13'151,6'-Tetraftuorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(5-lndanyl)Oxamyl)Valinyl]Amino-5-(2',3',51,61-Tetrafluoraphenoxy)-4 -Oxopentanoic acid; (SSj-S-lN-CNXMethylJOxamyOValinylJAmino-S^'.a'.S'.S'-TetrafluorophenoxyJ-^-Oxopentanoicacid; (3S)-3-[N-(N'-{n-Hepl:yl)Oxamyl)Valinyl]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid; (3S)-3-[N-(N1-(tert-Octyl)Oxamyl]Valinyl]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid; (SSJ-S-IIM^NXCyclohexylJOxamyl)ValinyllAnnino-B-tZ'.S'.S'.e'-TetrafluorophenoxyH-Oxopentanoicacid; (3S)-3-[N-(N'-(5-P)nenyl-3-Pyrazoly])Oxamyl)Valinyl]Amino-5-(2',3',51l61-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2,3,4,5-Tetrafluorophenyl)Oxamyl)ValinyqAmino-5-(2',3',5'16'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2,3,4,6-Tetrafluorophenyl)Oxamyl)Valinyi]Amino-5-(21,3>151,6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2,3,5,6-Tetrachlorophenyl)Oxamyl)Va!inyl]Amino-5-(2',3ll5',6'-Tetra1luorophenoxy}-4- Oxoperrtanoic acid; (3S)-3-[N-(N'-(2,3,4,5,6-Pentaf!uorophenyl)Oxamyl}Valinyl]Amino-5-(21l3'>5',61-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2-Ben2imida2olyl)Oxamyl)Valinyl]Amino-5-{2',3115',6'-Tetrafluorophenoxy}-4-Oxopentanoic acid; (3S)-3-tN-(N'-(1-Naphthyl)Oxamyl)Valinyl]Amino-5-(2',6'-Difluorophenoxy)-4-Oxopentanoicacid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Valfnyl]Amino-5-(2l,4',6'-Trifluorophenoxy)-4-Ox:opentanoicacid; (3S}-3-tN--(1-Naphthyl}Oxamyl)ValinyI]Amino-5-{Methylpheny]phosphinyloxy)-4-Oxopentanoicacid; (3RS)-3-[N-(N'-{1-Naphthy))Oxamyl)Valinyl]Amino-5-Fluoro-4-Oxopentanolcacld; (SSJ-S-tN-fN'KPhenyOOxamyOAIaninyllAmino-S^'.a'.S'.e'-TetrafluorophenoxyH-Oxopentanoicacid; (SSJ-S-IN-CN'^S.G.T.S-Tetrahydro-l-NaphthyllOxamyOAianinyllAmino-S^'.S'.S'.S'-TeltrafluoroptienoxyH- Oxopentanoic acid; (3S)-3-[N-{N'-(2-Phenylphenyl)Oxamyl)Alaninyl]Amino-5-{2',3ll5',6'-TetrafIuorophenoxy)-4-Oxopentanoic acid; {SSJ-S-tN-CN'^-BenzylphenyliOxamyllAlaninyllAmino-S-tZ'.S'.S'^'-TetrafluorophenoxyH-Oxopentanoic acid; {3S}-3-lN-(Nl-(1-Naphthylmethyl)Oxamyl)Alaniny]]Amino-5-(2',3',5'ta'-TettafluorophenQxy)-4- Oxopentanoic acid; (3S)-3-IN-(N1-(2-Phenoxypheny!}Oxamyl)Alaninyl]Amino-5-(2',3',5>,6'-Tetrafluoroptienoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(3-PheT»oxyiphenyl)Oxamyl)Alaninyl]Amino-5-(2l(3',5',6'-Tetraftuorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(4-Phenylphenyl)Oxamyl}AlaninyIJAmlno-5-C2',31,5',6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(Benzhydryl)Oxamyl)Alaninyl]Amino-5-{2',3',5>,61-TBtrafluorophenoxy)-4-Oxopen!tanoicacid; (3S)-3-[N-{N'-(2-Pli6nylphenyl)Oxamy/)AlaninyljAmino-5-(2'-Fluorophenoxy)-4-Oxopentanoicacid; (3S)-3-[N-(N1-(2-tert-Butylphenyl)Oxamyl)Alaninyl]Amino-5-(2l-Fluorophenoxy)-4-Oxapentanoicacidi; (3S)-3-[N-(N'-(2-Phenylphenyl)Oxamyl)A!aninyllAmino-5-(Diphenylphosphinoxy)-4-Oxopentanoicaci(j; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Alaninyl]Amino-5-(Diphenylphosphiny[oxy)-4-Oxopentanoicacid; (SSJ-S-tN-fN'^l-NaphthyOOxamyOLeucinyqAmino-S-ca'^'.e'-TrifluorophenoxyH-Oxopentanoicacid; (3S)-3-[NKNX1-Naphthyl)Oxamy()(tert-Butyl)GlycinyllAmino--5-<2I,3ll5l,6l-TetrafIuoraph6noxy)-4- Oxopentanoic acid; Oxopentanoic acid; Oxopentanoic acid; (3S)-3-[N-(N'-(1-Naphthyl}Oxamyl)Leucinyl]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoicacid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Leucinyl]Amino-5-(Methylphenylphosphinyloxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Leucinyl]Amino-5-Fluoro-4-Oxopentanoicacid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)Leucinyl]Amino-5-{Diphenylphosphmyloxy)-4-Oxopentanoicacid; (3S)-3-[N-(N'-(2-(1H-Tetrazo!-5-y!)Phenyl).Oxamyl)Valinyl3Amino-4-Oxobutanofcacid; (3S)-3-[N-(N'-(1-Adamantyl)Phenyi)Oxamyl)Valinyl]Am[no-4-Oxobutanoicacid; (3S)-3-[N-(N'-(Phenyl)Oxamyl)ValinylJAmino-4-Oxobutanoic acid ; (3S)-3-[N-(N'-(Benzyl)Oxamyl)Vaiinyl]Amino-4-Oxobutanoicacid; (3S)-3-[N-(N'-(Phenethyl)Oxamyl)Valinyl]Amino-4-Oxohutanoicacid; {3S)-3-(N-(N'-(2-Phenoxyphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid; (3S)-3-[N-{N1-(2-Naphthyl}Oxamyl)Valinyl]Amino-4-Oxobutanoicacid; (3S)-3-(N-(N'-(4-Chloro-1-Naphthyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid; {3S^N^NXS,6J,B-Tetrahydrx-1-Naphthyl)Oxamyl)Vallnyl]ArnincHj-Oxobutanofcacld; {3S)-3-[N-(N'-(1,2,3,4-Tetrahydro-1-Naphthyl)Oxamyl)Valinyl]Amino^f-Oxobutanotcacid; {3S)-3-[N-(N'-(1-Naphthylmethyl)Oxamyl)Valinyl]Am!no-4-Oxobutanoicacld; {SSJ-S-JN^N'-CI-NaphthyllOxamyOLeucinyllAmino^Oxobutanoicacid; Especially preferred are compounds selected from: (3S}-3-[N-(N'-(2-Fluoro-4-lodophenyl)Oxamyl)Valinyl3Amino-5-(21,3',5I,6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[M-(N'-(2-Chlorophenyl}Oxarnyl)Valinyl]Am!no-5-(2',3',5')6'-Tetrafluorophenoxy)-4-Oxopentanoic (3S)-3-[N-(N'-(2-Bromophenyl)Oxamyl)Va!inyl]Amino-5-(2',3',5'v6'-Tetrafluoraphenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(2-Fluoraphenyl)Oxamyl)Va)inyl]Amino-5-(2>,3>,5',6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(2-Trifluoromethylphenyl)Oxamyl)VaHnyl]Amino-5-(2',3',5',6'-Tetrafluoroph6noxy}-4- Oxopentanoic acid; (3S)-3-(N-(N'-(1-Anthryl)Oxamyl)Valinyl]Amino-5-{2',3'l5',6'-Tetrafluorophenoxy}-4-Oxopentanoicacid; (3S}-3-[N-(NI-(2-Tert-Butylphenyl)Oxamyl)Alaniny!]Amino-5-(2'13I,5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2-Trifluoromethylphenyl)Oxamy!)Alaninyl]Amino-5-{2',3',5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N1-(2,6-Difluorophenyl)Oxamyl)Alaninyl]Amino-5-(2I,3',5',6'-Tetrafluorophenoxy)-4- Oxopentanoic acid; (3S)-3-[N-(N'-(1-Naphthyl)Oxamyl)AlaninyllAmino-5-(2',3'l5'l6'-Tetrafluorophenoxy)-4-Oxoper(tanoicacid; (3S)-3-[N-(N'-(4-Methoxyphenyl)Oxamyl}Alaninyl]Amino-5-(2')3',5',6'-Tetraf!uorophenoxy}-4- Oxopentanoic acid; (3S)-3-[N-(N'-(2-Trifluoromethylphenyl)Oxamyl}Valinyl]Amino-4-Oxobutanoic acid; (3S)-3-[N-(N'-(2-tert-Butylmethylphenyl)Oxamyl)Valinyl]Amina-4-Oxobutanoicacid; (3S)-3-[N-(N'-(2-Benzylphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicactd; (3S)-3-[N-(N'-(2-PhenyiphBnyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid. Most preferably, the compound is (3S)-3-tN-(N'-(2-Tert-Butylp]ienyl)Oxamyl}Alaniny)]Amino-5-(21,3',51,6'-Tetrafluorophenoxy)-4-Oxopentanoicacid. The anti-MAdCAM antibody or antigen binding portion thereof is preferably an antibody as disclosed in W02005/067620, hereby Incorporated by reference in its entirety. In particular, all SEQ tD Nos referred to herein relate to the sequences actually disclosed in W02005/067620. Preferably the anti-MAdCAM antibody used in the invention specifically binds MAdCAM. Even more preferably, at least the CDR sequences of said antibody are human CDR sequences, or art antigen-binding portion of a human antibody. Preferably the antibody is a human antibody, more preferably an antibody that acts as a MAdCAM antagonist Another aspect of the invention is the use in the combination of the invention of the heavy and/or light chain of said anti-MAdCAM antibody or the variable region or other antigen-binding portion thereof, or nucleic acid molecules encoding any of the foregoing and a pharrnaceutically acceptable carrier. This aspect of the invention includes the use of fragments of any of the foregoing antibodies, including but not limited to Fab fragments, F(ab')2 fragments, single-chain Fv (scFv) fragments. Preferably, the anti-MAdCAM antibody is a human inhibitory anti-MAdCAM antibody selected from 1.7.2, 1.8.2, 6.14.2, 6.22.2, 6.34.2, 6.67.1, 6.73.2, 6.77.1, 7.16.6, 7.20.5, 7.26.4, 9.8.2, 6.22.2-mod, 6.34.2-mod, 6.67.1-mod, 6.77.1-mod or 7.26.4-mod as disclosed in W02005/067620. Preferably, the anti-MAdCAM antibody comprises a light chain comprising an amino acid sequence selected from SEQ ID NO: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 58, 62, 66 or 68 as disclosed in WO2005/067620 (with or without the signal sequence) or the variable region of any one af said amlno acid sequences, or one or more CDRs from these amino acid sequences. The anti-MAdCAM antibody preferably comprises a heavy chain comprising an amino acid sequence selected from SEQ ID NO: 2, 6,10, 14,18, 22, 26, 30, 34, 38, 42, 46, 52, 56, 60 or 64 as disclosed in WO2005/067620 (with or without the signal sequence) or the amino acid sequence of the variable region, or of one or more CDRs from said amino acid sequences. The anti-MAdCAM antibody preferably is a human anti-MAdCAM antibody comprising the amino acid sequence from the beginning of the CDR1 to the end of the CDR3 of any one of the above-mentioned sequences. The anti-MAdCAM antibody used in the invention can also be an anti-MAdCAM antibody comprising one or more FR regions of any of the above-mentioned sequences. The anti-MAdCAM antibody used in the combination o1 the Invention can also include an anti-MAdCAM antibody comprising one of the afore-mentioned amino acid sequences in which one or more modifications have been made. For example, cysteines in the antibody, which may be chemically reactive, are substituted with another residue, such as, without limitation, alanine or serine. The substitution can be at a non-canonical cysteine or at a canonical cysteine, The substitution can be made in a CDR or framework region of a variable domain or in the constant domain of an antibody. An anrfino acid substitution may also be made to eliminate potential proteolytic sites in the antibody. Such sites may occur in a CDR or framework region of a variable domain or in the constant domain of an antibody. Substitution of cysteine residues and removal of proteolytic sites may decrease the heterogeneity in the antibody product. Asparagine-glycine pairs, which form potential deamldafion sites, may be eliminated by altering one or both of the residues. An amino acid substitution may be made to add or to remove potential glycosylation sites in the variable region of an antibody used in the invention. The C-terminal lysine of the heavy chain of the anti-MAdCAM antibody used the invention may be cleaved. The heavy and light chains of the anti-MAdCAWI antibodies may optionally Include a signal sequence. Twelve preferred inhibitory human anti-MAdCAM monoclonal antibodies for use in the combination of the invention are described in detail in WO2005/067620: 1.7.2, 1.8.2, 6.14.2, 6.22.2, 6.34,2, 6.67.1, 6.73.2, 6.77.1, 7.16.6, 7.20.5, 7.26.4 and 9.8.2. Cfass and Subclass of anti-MAdCAM Antibodies The antibody may be an IgG, an IgM, an IgE, an !gA or an IgD molecule. Preferably the antibody is an IgG class and is an IgG1 lgG2, lgG3 or IgG* subclass. More preferably, the anti-MAdCAM antibody is subclass lgG2. or lgG4. More preferably, the anti-MAdCAM antibody is the same class and subclass, as antibody 1.7.2, 1.8.2, 7.16.6, 7.20.5, 7.26.4, 6.22.2-mod, 6.34.2-mod, 6.67.1-mod, 6.77.1-mod or 7.26.4-mod which is lgG2, or 6.14.2, 6.22.2, 6.34.2, 6.67.1, 6.73.2, 6.77.1 or 9.8.2, which is lgG4as described in WO2005/067620. The class and subclass of anti-MAdCAM antibodies may be determined by any method known in the art. In general, the class and subclass of an antibody may be determined using antibodies that are specific for a particular class and subclass of antibody. Such antibodies are available commercially. ELISA, Western Blot as well as other techniques can determine the class and subclass. Alternatively, the class and subclass may be determined by sequencing all or a portion of the constant domains of the heavy and/or light chains of the antibodies, comparing their amino acid sequences to the known amino acid sequences of various classes and subclasses of immunoglobulins, and determining the class and subclass of the antibodies as the class showing the highest sequence identity. Species and Molecule Selectivity The anti-MAdCAM antibody used in the combination of the invention demonstrates both species and molecule selectivity. The anti-MAdCAM antibody may bind to human, cynomolgus or dog MAdCAM. Other anti-MAdCAM antibodies used in the combination of the invention do not bind to a New World monkey species such as a marmoset. One may determine the species selectivity for the anti-MAdCAM antibody using methods well known in the art. For Instance, one may determine species selectivity using Western blot, FACS, ELISA or immunohistochemistry. In a preferred embodiment, one may determine the species selectivity using immunohistochemistry. An anti-MAdCAM antibody used in the combination of the invention that specifically binds MAdCAM has selectivity for MAdCAWI over VCAM, fibronectin or any other antigen that is at least 10 fold, preferably at least 20, 30, 40, 50, 60, 70, 80 or 90 fold, most preferably at least 100 fold. Preferably the anti-MAdCAM antibody does not exhibit any appreciable binding to VCAM, fibronectin or any other antigen other than MAdCAM. One may determine the selectivity of the anti-MAdCAM antibody for MAdCAM using methods well known in the art following the teachings of the specification. For instance, one may determine the selectivity using Western blot, FAGS, ELISA, or immunohistochemistry. Binding Affinity of anti-MAdCAM antibodies to MAdCAM The anti-MAdCAM antibodies used in the combination of the invention preferably specifically bind to MAdCAM with high affinity. One anli-MAdCAM antibody used in the combination of the invention' specifically binds to MAdCAM with a Kd of 3 x 10"8 M or less, as measured by surface plasmon resonance, such as BIAcore. Preferably, the antibody specifically binds to MAdCAM with a Kd of 1 x 10'8 or less or 1 x 10'° M or less. More preferably, the antibody specifically binds to MAdCAM with a K,61-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-(N'-(2-Bromophenyl)Oxamyl)Valiny]lAmino-5-{2l13',5I,6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S}-3-[N-(N'-(2-Fluorophenyl)Oxamyl)Vallnyl]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4-Oxopentanolc acid; (3S)-3-[N-(N'-(2-Trifluoromethylphenyl)Oxamyl)Valiny]]Amino-5-(2',3',5',6'-Tetrafluorophenoxy)-4-Oxopentanoic acid; (3S)-3-[N-{N'-(2-T6rt-Butylpheny1)Oxamyl)Alanlnyl]Amino-5-(2',3',5',6'-Tetraf!uorophenoxy)-4-Oxopentanoic acid; (3S}-3-[N-(N1-(2-Trifluoromethylphenyl)Oxamy))Alaninyl]Amino-5-(2',3l,5'16'-Tetrafluorophenoxy)-4-Oxopentanoic acid; Oxopentanoic acid; (SSJ-S-IN-fN'-d-Naphthyl)OxamylJAIaninyl]Amino-5(2,3,5,6-TeirafluorophenoxyH-Oxopentanoicacid; {3S)-3-[N-(N'-(4-Methoxyphenyl)Oxamyl)Alaninyl]Amino-5-(2',3',5',61-Tetrafluorophenoxy)-4- Oxopentanoic acid; {3S)-3-[N-(N'-(2-Trifluorormethylphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid; (3S}-3-[N-(N'-(2-tert-Butylmethylphenyl)Oxamyl)Valnyt]Amino-4-Oxobutanoicacid; (3S)-3-[N-(N'-(2-Benzylphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid; (3S)-3-[N-(N'-(2-Phenylphenyl)Oxamyl)Valinyl]Amino-4-Oxobutanoicacid. 5. The combination of. any previous claim, wherein the anti-MAdCAM antibody or antigen-binding portion thereof is a human monoclonal antibody or antigen-binding portion. 6. The combination of claim 5, wherein the antibody or portion possesses at least one of the following properties: (a) binds to human cells; (b) has a selectivity for MAdCAM over VCAM or fibronectin of at least 1 00 fold; (c) binds to human MAdCAM with a Kd of 3 x 1 0-1D M or less; or (d) inhibits the binding of α4β7 expressing cells to human MAdCAM. (e) inhibits the recruitment of lymphocytes to gastrointestinal lymphoid tissue. 7. The combination according to any of claims 5 or 6, wherein said antibody or antigen-binding portion inhibits binding of human MAdCAM to α4β7, and wherein the antibody or portion thereof has at least one of the following properties: (a) cross-competes with a reference antibody for binding to MAdCAM; (b) competes with a reference antibody for binding to MAdCAM; (c) binds to the same epitope of MAdCAM as a reference antibody; (d) binds to MAdCAM with substantially the same Kd as a reference antibody; (e) binds to MAdCAM with substantially the same off rate as a reference antibody; wherein the reference antibody is selected from the group consisting of. monoclonal antibody 1.7.2, monoclonal antibody 1.8.2, monoclonal antibody 6.14.2, monoclonal antibody 6.22.2, monoclonal antibody 6.34.2, monoclonal antibody 6.67.1, monoclonal antibody 6.73.2, monoclonal antibody 6.77.1, monoclonal antibody 7.16.6, monoclonal antibody 7.20.5, monoclonal antibody 7.26.4, monoclonal antibody 9.8.2, monoclonal antibody 6.22.2-mod, monoclonal antibody 6.34.2-mod, monoclonal antibody 6.67,1-mod, monoclonal antibody 6.77.1-mod and monoclonal antibody 7.26.4-mod. 8. The combination according to any of claims 5 to 7, wherein the monoclonal antibody or an antigen- binding portion thereof is selected from the following antibodies: (a) the heavy chain comprises the heavy chain CDR1, CDR2 and CDR3 amino acid sequences of a reference antibody selected from the group consisting of: 1.7.2, 1.8.2, 6.14.2, 6.22.2, 6.34.2, 6.67.1, 6.73.2, 6.77.1, 7.16.6,7.20.5, 7.26.4, 9.8.2, 6.22.2-mod, 6.34,2-mod, 6.67. Mnod, 6.77.1-mod and 7.26.4- mod (b) the light chain comprises the light chain CDR1, CDR2 and CDR3 amino acid sequences of a reference antibody selected from the group consisting of. 1.7,2, 1.8.2, 6.14.2, 6.22.2, 6,34.2, 6.67,1, 6.73.2, 6.77.1, 7.16.6, 7.20.5, 7.26.4, 9.8.2, 6.22.2-mod, 6,34.2-mod, 6.67.1-mod, 6.77.1-mod and 7.26.4- mod {c) the antibody comprises a heavy chain of (a) and a light chain of (b); and (d) the antibody of (c) wherein the heavy chain and light chain CDR amino acid sequences are selected from the same reference antibody. 9. The combination of an anti-α4β7 integrin antibody or antigen binding portion thereof with a caspase inhibitor as defined in any of claims 2 to 4. 10. The use of the combination of any previous claim for the manufacture of a medicament for the treatment of liver fibrosis. 11. The use of claim 10, wherein the liver fibrosis is Hepatrtic C associated liver fibrosis, alcoholic liver disease or non-alcoholic steatohepatitis. 12. A pharmaceutical composition of the combination of any of claims 1 to 9 with a pharmaceutically acceptable carrier or excipient.