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Published on: April 18, 2019

Activities of doripenem (S-4661) against drug-resistant clinical pathogens

Ronald N Jones1, Holly K Huynh, Douglas J Biedenbach

  • 1The JONES Group/JMI Laboratories, Inc., North Liberty, Iowa 52317, USA. ronald-jones@jmilabs.com

Antimicrobial Agents and Chemotherapy
|July 27, 2004
PubMed

Insights

Doripenem demonstrated potent activity against drug-refractory bacteria, including extended-spectrum beta-lactamase-producing enteric bacilli and penicillin-resistant streptococci. This new carbapenem showed promising efficacy where other antibiotics failed, offering a potential new treatment option.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pharmacology

Background:

  • Antimicrobial resistance is a growing global health threat, necessitating the development of novel antibiotics.
  • Carbapenems are a critical class of antibiotics used to treat serious bacterial infections.
  • Drug-refractory bacterial isolates pose a significant challenge in clinical settings.

Purpose of the Study:

  • To evaluate the in vitro activity of doripenem against a diverse collection of drug-refractory bacterial isolates.
  • To compare the efficacy of doripenem with other carbapenems against specific resistant bacterial strains.

Main Methods:

  • Testing of doripenem and comparator carbapenems against 394 drug-refractory isolates.
  • Determination of minimum inhibitory concentrations (MICs) and MIC90 values.
  • Inclusion of endemic extended-spectrum beta-lactamase- and AmpC-producing enteric bacilli, carbapenem-resistant nonfermentative gram-negative bacilli, and penicillin-resistant streptococci.

Main Results:

  • Doripenem exhibited potent activity against extended-spectrum beta-lactamase- and AmpC-producing enteric bacilli (MIC90s: 0.03 to 0.5 microg/ml), often exceeding that of comparator carbapenems.
  • A higher proportion of carbapenem-resistant nonfermentative gram-negative bacilli were inhibited by doripenem at <=4 microg/ml.
  • Doripenem was the most active carbapenem against penicillin-resistant streptococci (MIC90: 1 to 4 microg/ml).

Conclusions:

  • Doripenem displays significant in vitro activity against a broad spectrum of drug-refractory gram-negative and gram-positive bacteria.
  • Its efficacy against challenging pathogens like ESBL-producers and penicillin-resistant streptococci suggests a valuable role in combating antimicrobial resistance.
  • Doripenem represents a promising therapeutic option for infections caused by multidrug-resistant organisms.

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