title: Practical applications and feasibility of efflux pump inhibitors in the clinic--a vision for applied use.
abstract: The world of antibiotic drug discovery and development is driven by the necessity to overcome antibiotic resistance in common Gram-positive and Gram-negative pathogens. However, the lack of Gram-negative activity among both recently approved antibiotics and compounds in the developmental pipeline is a general trend despite the fact that the plethora of covered drug targets are well-conserved across the bacterial kingdom. Such intrinsic resistance in Gram-negative bacteria is largely attributed to the activity of multidrug resistance (MDR) efflux pumps. Moreover, these pumps also play a significant role in acquired clinical resistance. Together, these considerations make efflux pumps attractive targets for inhibition in that the resultant efflux pump inhibitor (EPI)/antibiotic combination drug should exhibit increased potency, enhanced spectrum of activity and reduced propensity for acquired resistance. To date, at least one class of broad-spectrum EPI has been extensively characterized. While these efforts indicated a significant potential for developing small molecule inhibitors against efflux pumps, they did not result in a clinically useful compound. Stemming from the continued clinical pressure for novel approaches to combat drug resistant bacterial infections, second-generation programs have been initiated and show early promise to significantly improve the clinical usefulness of currently available and future antibiotics against otherwise recalcitrant Gram-negative infections. It is also apparent that some changes in regulatory decision-making regarding resistance would be very helpful in order to facilitate approval of agents aiming to reverse resistance and prevent its further development.
authors.affiliation: Mpex Pharmaceuticals Inc., 3030 Bunker Hill Street, San Diego, CA 92109, USA.
authors.forename: Olga
authors.initials: O
authors.lastname: Lomovskaya
authors.forename: Keith A
authors.initials: KA
authors.lastname: Bostian
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology; D002473:Cell Wall / Q000187:drug effects / Q000502:physiology; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000502:physiology; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D026901:Membrane Transport Proteins / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D026901:Membrane Transport Proteins