Introduction to antibiotic resistance

The inexorable rise in multidrug-resistant Gram-negative bacteria has been widely reported. Multiple modes of resistance often present in a single strain of bacteria, and this may also be combined with an increase in virulence, both of which are leading to a significant increase in morbidity and mortality in patients. Against this background, the absolute number of new antibiotics licensed has declined especially for Gram-negative multidrug-resistant pathogens. The reasons for this failure are presented here: market issues, big pharma changes, regulatory constraints, difficulties in finding drugable targets and, lastly, suitable compounds worthy of full development.