Temocillin was marketed by Beecham Pharmaceuticals in the UK in the 1980s but achieved little commercial success and was withdrawn, though it remained available via the manufacturer’s medical department. Presently licensed to Eumedica, temocillin is being re-launched in the UK and Belgium for treating UTI, sepsis, and respiratory infections by ESBL (Extended-spectrum beta-lactamases) and AmpC-producing Enterobacteriaceae. It acts by inhibiting the synthesis of the peptidoglycan layer of bacterial cell walls. It irreversibly binds to the active site of specific transpeptidases and carboxypeptidases known as Penicillin Binding Proteins (PBP), preventing peptidoglycan production.

Carumonam is a monobactam antibacterial agent. It was highly active in vitro against members of the family Enterobacteriaceae, Pseudomonas aeruginosa, and Haemophilus influenzae and weakly active against Streptococcus pneumoniae, but it was not active against Staphylococcus aureus. The excellent activity of carumonam against Gram-negative bacteria is related to its high affinity for their penicillin-binding proteins. It is indicated for the treatment of urinary tract infections, chronic respiratory infections, biliary tract infections, peritonitis, sepsis. Another factor that contributes to the excellent activity of carumonam against Gram-negative bacteria is its resistance to beta-lactamases. Adverse effects of the carumonam were limited to phlebitis at the intravenous infusion site; bloody diarrhea.

Cefsulodin is a third-generation of cephalosporin antibiotic with a narrow spectrum of activity. It has a specific activity against Pseudomonas aeruginosa. Cefsulodin’s targets are bacterial penicillin binding proteins. Drug is indicated for the treatment of infections of lower respiratory tract, skin and skin structures, urinary tract, bone and joint; treatment of gynecological infections; treatment of intra-abdominal infections; treatment of septicemia and CNS infections including meningitis caused by susceptible strains of specific microorganisms. Cefsulodin appears to be well tolerated and relatively free of any significant toxicity except for nausea and vomiting.

Polymyxin B is a lipopeptide antibiotic isolated from Bacillus polymyxa. Its basic structure consists of a polycationic peptide ring and a tripeptide side chain with a fatty acid tail. Polymyxin B is a mixture of at least four closely related components, polymyxin B1 to B4, with polymyxin B1 and B2 being the two major components. Polymyxin B acts on Gram-negative bacteria by interacting with lipopolysaccharide (LPS) of the outer membrane and destabilizing it. Polymyxin B is indicated for the treatment of many bacterial diseases such as meningeal infections, urinary tract infections and bacteremia.