Tosufloxacin is a fluoroquinolone antibacterial agent. Tosufloxacin is an inhibitor of bacterial DNA gyrase and topoisomerase IV. Tosufloxacin is indicated for the treatment of various infections such as skin, respiratory, urinary, gynecologic, ophthalmologic, otolaryngologic, dental infections. Fluoroquinolones including tosufloxacin have a potential risk of inducing cartilage and joint toxicity in children. It is also associated with severe thrombocytopenia and nephritis, and hepatotoxicity.

Prulifloxacin is a prodrug of ulifloxacin which has been approved in Italy, Japan, China, India and Greece, for treatment of infections caused by susceptible bacteria, in the following conditions: acute uncomplicated lower urinary tract infections (simple cystitis); complicated lower urinary tract infections; acute exacerbation of chronic bronchitis; gastroenteritis, including infectious diarrheas. Like other fluoroquinolones, prulifloxacin prevents bacterial DNA replication, transcription, repair and recombination through inhibition of bacterial DNA gyrase.

Cefprozil, an oral cephalosporin antibiotic, is a mixture of antibiotic BMY-28100 (Z- or cis-isomer) and antibiotic BMY-28167 (E- or trans -isomer), the mixture having a Z- to E- isomer ratio in the range of 89:11 to 94:6. BMY-28167 (E- or trans -isomer) is less active when compared with BMY-28100 or isomeric mixture. There were no remarkable differences in the toxicity of the cis isomer, the trans isomer, or cefprozil (the isomeric mixture).

Cefquinome is a 4th generation cephalosporin which is active against a broad spectrum of Gram positive and Gram negative bacteria. As many cephalosporin it acts by binding to bacterial PBP and thus inhibiting the cell wall synthesis. Cefquinome is approved for veterinary use in cattles with respiratory tract infections, skin infections, bacterial mastitis and septicaemia.

Cefpirome is a semisynthetic, broad-spectrum, fourth-generation cephalosporin with antibacterial activity. Cefpirome binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. PBPs are enzymes involved in the terminal stages of assembling the bacterial cell wall and in reshaping the cell wall during growth and division. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This results in the weakening of the bacterial cell wall and causes cell lysis. Cefpirome is an injectable extended-spectrum or 'fourth generation' cephalosporin. Its antibacterial activity encompasses many of the pathogens involved in hospital-acquired infections such as Enterobacteriaceae, methicillin-susceptible Staphylococcus aureus, coagulase-negative staphylococci and viridans group streptococci. Cefpirome also has in vitro activity against Streptococcus pneumoniae regardless of penicillin susceptibility. It is stable against most plasmid- and chromosome-mediated beta-lactamases, with the exception of the extended-spectrum plasmid-mediated SHV enzymes. Intravenous cefpirome 2g twice daily has shown clinical efficacy comparable to that of ceftazidime 2g 3 times daily in the treatment of hospitalised patients with moderate to severe infections. Clinical response and bacteriological eradication rates were similar in patients with severe pneumonia or septicaemia treated with either cefpirome or ceftazidime. Cefpirome appeared more effective than ceftazidime in the eradication of bacteria in patients with febrile neutropenia in 1 study; however, clinical response rates were similar in the 2 treatment groups. The tolerability of cefpirome appears similar to that of ceftazidime and other third generation cephalosporins, diarrhoea being the most frequently observed event. Thus, cefpirome is likely to be a valuable extended-spectrum agent for the treatment of severe infections. Cefpirome offers improved coverage against some Gram-positive pathogens and Enterobacteriaceae producing class I beta-lactamases compared with the third generation cephalosporins, although this has yet to be demonstrated in clinical trials.

Cefodizime is a third-generation cephalosporin with a broad spectrum of antibacterial activity. Administered intravenously or intramuscularly 1 to 4 g of cefodizime daily for an average of 7 to 10 days produces a clinical cure in 80 to 100% of patients (adults, elderly or children) with upper or lower respiratory tract infections or urinary tract infections. In comparative trials cefodizime was as effective as other third generation cephalosporins. A single dose of cefodizime (1 or 2 g) is also useful in treating lower urinary tract infections. Urogenital gonorrhoea, whether caused by beta-lactamase producing or non-beta-lactamase producing Neisseria gonorrhoeae, is very effectively treated by single dose therapy with intramuscular cefodizime. Preliminary data from a small number of patients indicates that cefodizime may also be useful in the treatment of otitis media, sinusitis and gynaecological infections, and for the prophylaxis or treatment of surgical infections. The clinical efficacy of cefodizime compared to other third generation cephalosporins is superior to that predicted from in vitro results. This superior activity of cefodizime may be related to the relatively long elimination half-life of the drug or its ability to modify some functions of the immune system--a potentially important finding awaiting further investigation. Cefodizime is well tolerated and has a tolerability profile similar to other members of its class with systemic adverse events being primarily gastrointestinal or dermatological. Cefodizime may be more convenient to administer than some other agents of its class as it may be given once or twice daily. While there are no trials comparing cefodizime to other third generation cephalosporins in immunosuppressed populations, preliminary information indicates cefodizime may be useful in this group. Cefodizime targets penicillin-binding proteins (PBPs) 1A/B, 2, and 3 resulting in the eventual death of the bacterial cell. In vivo experimental models of infection showed that bacterial clearance by this drug is at least as effective compared with other 3rd generation cephalosporins. It has a similar adverse effect profile to other 3rd generation cephalosporins which is mainly being limited to gastrointestinal or dermatological side effects. It is not currently approved by the FDA for use in the United States.

Garenoxacin is an antibacterial agent active against a range of aerobic Gram-positive and Gram-negative bacteria. It exerts its action by inhibiting bacterial DNA gyrase and topoisomerase IV. The drug was withdrawn from the market in Europe and was never approved in the USA. Garenoxacin is still marketed in Japan under the name Geninax.

Bekanamycin is an aminoglycoside and is a congener of kanamycin. It is given topically as the sulfate for the treatment of eye infections. It is reported to be more toxic than kanamycin A. Antibiotic complex produced by Streptomyces kanamyceticus Okami & Umezawa from Japanese soil. There are no known interactions with other drugs.

Josamycin is a macrolide antibiotic produced by Streptomyces narbonensis var. josamyceticus. Macrolides are inhibitors of protein synthesis. They impair the elongation cycle of the peptidyl chain by specifically binding to the 50S subunit of the ribosome. Josamycin has antimicrobial activity against a wide spectrum of pathogens. It is similar to erythromycin, but does not induce macrolide resistance in staphylococci and appears to have a lower incidence of gastrointestinal side effects. Josamycin is under investigation in US.

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.