Efficacy of the Novel Antibiotic POL7001 in Preclinical Models of Pseudomonas aeruginosa Pneumonia

Antimicrob Agents Chemother. 2016 Jul 22;60(8):4991-5000. doi: 10.1128/AAC.00390-16. Print 2016 Aug.

Abstract

The clinical development of antibiotics with a new mode of action combined with efficient pulmonary drug delivery is a priority against untreatable Pseudomonas aeruginosa lung infections. POL7001 is a macrocycle antibiotic belonging to the novel class of protein epitope mimetic (PEM) molecules with selective and potent activity against P. aeruginosa We investigated ventilator-associated pneumonia (VAP) and cystic fibrosis (CF) as indications of the clinical potential of POL7001 to treat P. aeruginosa pulmonary infections. MICs of POL7001 and comparators were measured for reference and clinical P. aeruginosa strains. The therapeutic efficacy of POL7001 given by pulmonary administration was evaluated in murine models of P. aeruginosa acute and chronic pneumonia. POL7001 showed potent in vitro activity against a large panel of P. aeruginosa isolates from CF patients, including multidrug-resistant (MDR) isolates with adaptive phenotypes such as mucoid or hypermutable phenotypes. The efficacy of POL7001 was demonstrated in both wild-type and CF mice. In addition to a reduced bacterial burden in the lung, POL7001-treated mice showed progressive body weight recovery and reduced levels of inflammatory markers, indicating an improvement in general condition. Pharmacokinetic studies indicated that POL7001 reached significant concentrations in the lung after pulmonary administration, with low systemic exposure. These results support the further evaluation of POL7001 as a novel therapeutic agent for the treatment of P. aeruginosa pulmonary infections.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacokinetics
  • Anti-Bacterial Agents / pharmacology*
  • Cystic Fibrosis / microbiology
  • Lung / drug effects
  • Lung / microbiology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microbial Sensitivity Tests
  • Pneumonia, Ventilator-Associated / microbiology
  • Pseudomonas Infections / microbiology
  • Pseudomonas aeruginosa / drug effects*
  • Pseudomonas aeruginosa / pathogenicity
  • Respiratory Tract Infections / microbiology

Substances

  • Anti-Bacterial Agents

Grants and funding

This work has been supported by the European Commission (NABATIVI-223670, EU-FP7-HEALTH-2007-B, to Alessandra Bragonzi and Daniel Obrecht) and Italian Cystic Fibrosis Research Foundation (FFC#10/2011 to Alessandra Bragonzi and Daniel Obrecht) with the contribution of the Delegazione FFC di Milano. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.