Introduction: standards of antibacterial performance

The development and clinical use of antimicrobial agents continue to evolve in line with new science, understanding and needs. While antimicrobial resistance remains an important determinant for drug development and therapeutic choice, pharmacokinetic and pharmacodynamic parameters are having an ever-increasing importance in defining performance targets for new and established agents. Recently licensed new therapies are largely directed at serious hospital-associated Gram-positive infections, whereas in the community, therapeutic choice remains dependent on well-established agents from limited classes of antimicrobials. In order to maximise the benefits from such agents, it is appropriate that dosage regimens and antibacterial choices be reviewed in the light of new knowledge, particularly in the area of pharmacokinetics and pharmacodynamics. Antimicrobial resistance continues to evolve, notably within respiratory pathogens, therefore steps must be taken to maintain optimum therapeutic outcomes and also limit the development and spread of resistant strains. Whilst changes in patient and physician attitudes and behaviour towards better quality prescribing are important, new agents must also be developed to provide adequate coverage for resistant pathogens. Development times for novel agents and classes of antimicrobials are long, with uncertain safety profiles and chances of success. Thus, the development of new formulations of existing agents, designed to overcome current resistance patterns, constitutes a potentially important additional strategy towards appropriate prescribing.