Section Review Anti-infectives: The future role of quinolones

Abstract

Quinolones, such as ciprofloxacin and ofloxacin, have gained wide acceptance for the treatment of bacterial infections of the respiratory tract, urinary tract, skin and soft tissues, as well as sexually transmitted diseases. Good pharmacokinetic profiles and potent activities against a wide range of Gram-negative and Gram-positive pathogens result in the use of these antibacterials in both hospital and community settings. Although recently developed clinical quinolones dominate in the chemotherapy of various bacterial infections, their use is restricted by limited activities against a number of clinically-important Gram-positive bacteria such as Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and enterococci. Ciprofloxacin, the market leader, also has low potency against anaerobes. Bacterial resistance (such as in Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus) to ciprofloxacin is increasing rapidly. Many quinolone compounds are being synthesised to address these drawbacks. The new quinolones currently under development are characterised by enhanced activities against streptococci, staphylococci, enterococci and anaerobes. Although the treatment of traditional bacterial infections is at present the focus of quinolone research, the future role of quinolones will extend current applications to include new indications of bacterial infections and other non-bacterial diseases. This review will concentrate on the more recently developed quinolones which possess significantly more therapeutic value than existing quinolones, and will provide information on those compounds under commercial development with major therapeutic potential. Recent developments in research into the identification of quinolones for the treatment of tuberculous, cancer, viral, fungal infections and parasitic diseases will also be discussed.