COMBINATION THERAPY WITH AMIDINE SUBSTITUTED BETA-LACTAM COMPOUNDS AND BETA-LACTAMASE INHIBITORS FOR INFECTIONS WITH ANTIBIOTIC RESISTANT BACTERIAL STRAINS

1 . A composition comprising a compound of formula (I)

characterized in that

R1 and R2 represent methyl,

R3 represents —O—(SO 2 )OH,

X represents CH,

Z represents a two carbon alkyl-chain, substituted with a carboxy substituent,

Y represents O,

A represents phenyl substituted with a substituent of the following formula

wherein

R1b and R2b represent hydrogen,

R3b represents aminoethyl, azetidine, pyrrolidine or piperidine,

Q represents a bond,

* is the linkage site to the residue represented by A, and

l represents 0

and the salts thereof, the solvates thereof and the solvates of the salts thereof, in combination with at least one β-lactamase inhibitor (BLI) selected from the group comprising clavulanic acid, tazobactam, sulbactam and other BLIs belonging to the groups of lactam inhibitors, diazabicyclooctane inhibitors, transition state analog inhibitors and/or metallo-β-lactamase inhibitors

and

at least one additional β-lactamase selected from the groups of class C AmpC β-lactamases and/or class A, class B, class C and/or class D carbapenemases.

2 . A composition as defined in claim 1 , wherein the compound of formula I is selected from the group comprising compounds of formulae (I-a), (I-b), (I-c), (I-d), (I-e), (I-f), and (I-g),

3 . A composition as defined in claim 1 wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam.

4 . A composition as defined in claim 1 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of clavulanic acid is 0.1-0.6 g, wherein the dose of tazobactam is 0.1-10 g, and wherein the dose of sulbactam is 0.25 g to 4.0 g.

5 . A composition as defined in claim 1 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of clavulanic acid is 0.25-0.6 g, wherein the dose of tazobactam is 0.25-2.0 g, and wherein the dose of sulbactam is 0.25 to 2.0 g.

6 . A composition as defined in claim 1 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of the compound of formula (I) and the BLI are administered at a ratio selected from the following group of ratios: 100:1 to 1:100, 10:1 to 1:10, and 5:1 to 1:5.

7 . A composition as defined in claim 2 , wherein the compound is a compound of formula (I-g).

8 . A method for the treatment or prophylaxis of a subject having an infection caused by Gram-negative bacteria that produce at least one or more class A and/or class D extended-spectrum β-lactamase (ESBL) which comprises administering to the subject a composition of claim 1 .

9 . The method of claim 8 , wherein the Gram-negative bacteria are selected from the genus of Enterobacteriaceae and non-fermenting strains.

10 . A composition as defined in claim 2 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam.

11 . A composition as defined in claim 2 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of clavulanic acid is 0.1-0.6 g, wherein the dose of tazobactam is 0.1-10 g, and wherein the dose of sulbactam is 0.25 g to 4.0 g.

12 . A composition as defined in claim 2 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of clavulanic acid is 0.25-0.6 g, wherein the dose of tazobactam is 0.25-2.0 g, and wherein the dose of sulbactam is 0.25 to 2.0 g.

13 . A composition as defined in claim 2 , wherein the BLI is selected from the group consisting of clavulanic acid, tazobactam, and sulbactam, and wherein the dose of the compound of formulae (I-a) to (I-g) and the BLI are administered at a ratio selected from the following group of ratios: 100:1 to 1:100, 10:1 to 1:10, and 5:1 to 1:5.

14 . A method for the treatment or prophylaxis of a subject having an infection caused by Gram-negative bacteria that produce at least one or more class A and/or class D extended-spectrum β-lactamase (ESBL) which comprises administering to the subject a composition of claim 2 .

15 . The method of claim 14 , wherein the Gram-negative bacteria are selected from the genus of Enterobacteriaceae and non-fermenting strains.