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Updated: Aug 9, 2026
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Published on: November 16, 2016
In vitro activities of LY333328 and comparative agents against nosocomial gram-positive pathogens collected in a 1997
M L Zeckel1, D A Preston, B S Allen
1Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USA.
Abstract:
The in vitro activity of LY333328 was evaluated for 1,479 nosocomial gram-positive pathogens isolated in 12 countries during 1997. LY333328 MICs at which 90% of the isolates tested were inhibited for Enterococcus faecalis (n = 351), Enterococcus faecium (n = 100), Staphylococcus aureus (n = 593), coagulase-negative Staphylococcus species (n = 325), and Streptococcus pneumoniae (n = 110) were 1, 1, 2, 2, and 0.015 microg/ml, respectively. LY333328 demonstrated potent activity against isolates of vancomycin-resistant enterococci, oxacillin-resistant staphylococci, and penicillin-resistant pneumococci.
Insights
The novel antibiotic LY333328 shows potent in vitro activity against a wide range of gram-positive pathogens. It is particularly effective against resistant strains like vancomycin-resistant enterococci and oxacillin-resistant staphylococci.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Nosocomial infections caused by gram-positive pathogens pose a significant clinical challenge.
- The emergence of antimicrobial resistance, including vancomycin-resistant enterococci (VRE), oxacillin-resistant Staphylococcus aureus (ORSA), and penicillin-resistant Streptococcus pneumoniae (PRSP), necessitates the development of new therapeutic agents.
- Understanding the in vitro activity spectrum of novel antibiotics is crucial for guiding clinical use.
Purpose of the Study:
- To evaluate the in vitro antibacterial activity of LY333328 against a large collection of clinically relevant gram-positive pathogens.
- To determine the minimum inhibitory concentrations (MICs) of LY333328 for key gram-positive species, including resistant isolates.
Main Methods:
- Prospective collection of 1,479 nosocomial gram-positive bacterial isolates from 12 countries in 1997.
- Determination of LY333328 minimum inhibitory concentrations (MICs) using standard microbiological methods.
- MIC90 values were calculated for Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, coagulase-negative Staphylococcus species, and Streptococcus pneumoniae.
Main Results:
- LY333328 exhibited potent in vitro activity against all tested gram-positive pathogens.
- MIC90 values were low, including 1 microg/ml for Enterococcus faecalis and Enterococcus faecium, 2 microg/ml for Staphylococcus aureus and coagulase-negative staphylococci, and 0.015 microg/ml for Streptococcus pneumoniae.
- Notably, LY333328 demonstrated significant activity against vancomycin-resistant enterococci, oxacillin-resistant staphylococci, and penicillin-resistant pneumococci.
Conclusions:
- LY333328 possesses broad-spectrum in vitro activity against clinically important gram-positive bacteria.
- The compound is highly effective against multidrug-resistant gram-positive pathogens, suggesting its potential as a valuable therapeutic option.
- Further clinical investigation of LY333328 is warranted for the treatment of gram-positive nosocomial infections.
