New fluoroquinolones: a class of potent antibiotics.

The discovery of antibiotics opened a new era in the treatment against several pathogenic microorganisms that can disable or kill humans. The appearance of the fluoroquinolones (based on nalidixic acid, 4-quinolone-3-carboxylates), in the early 1980's, gave a new impetus in the treatment of infectious diseases. Despite these favourable properties, the earlier fluoroquinolones had limited potency against some clinically important organisms, especially Gram-positive pathogens so that the development of resistance to these organisms has become a serious problem. Thus the development of new fluoroquinolones with a better pharmacokinetic profile, potency, broad spectrum of activity, solubility, prolonged serum half-life and oral and parenteral routes of administration has been a major focus on recent research. The increasing interest in this class led me to review the promising new fluoroquinolones in clinical trials.