The activity of the methylpiperazinyl fluoroquinolone CG 5501: a comparison with other fluoroquinolones

Abstract

The in-vitro activity of CG 5501 against a wide range of recent clinical isolates was compared with that of three fluoroquinolones. CG 5501 inhibited 90% of the species of the family Enterobacteriaceae at 0.5 mg/L or less, exceptions being Enterobacter spp. (MIC90 2 mg/L) and Serratia spp. (MIC90 4 mg/L). Ninety per cent of Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Acinetobacter spp. were inhibited by 16, 4 and 1 mg/L respectively. CG 5501 had high activity against Gram-positive cocci, 90% of staphylococci being inhibited at 2 mg/L. Methicillin-resistant Staphylococcus aureus strains were generally ciprofloxacin-resistant yet were all susceptible to 4 mg/L or less of CG 5501. Isolates of Streptococcus pneumoniae were eight-fold more susceptible to CG 5501 (MIC90 0.5 mg/L) than to ciprofloxacin (MIC90 4 mg/L) and the former had a similar activity to that of trovafloxacin and sparfloxacin. Enterococcus faecalis was generally two- to four-fold more susceptible to CG 5501 or trovafloxacin than to ciprofloxacin. CG 5501 and trovafloxacin had high activity against Bacteroides fragilis (MIC90 0.25 mg/L). Five strains of Chlamydia spp. were inhibited by < or =0.12 mg/L of CG 5501; sensitive and multiresistant strains of Mycobacterium tuberculosis were inhibited by < or =0.5 mg/L of CG 5501. The high activity and breadth of its antibacterial spectrum suggests that CG 5501 should be useful in a wide range of clinical infections.

Contribution of the R8 substituent to the in vitro antibacterial potency of besifloxacin and comparator ophthalmic fluoroquinolones

“…The MIC data for the ATCC quality control strains of E. faecalis , S. aureus , S. pneumoniae , E. coli , and P. aeruginosa were similar to previously published MIC values for besifloxacin, moxifloxacin, MCl, and gatifloxacin 5,8,14–18. Little has been published about the antibacterial potency of GCl, and no manuscripts that describe the antibacterial potency of BMO have been identified in the literature 7…”

Multiple-Dose Pharmacokinetics and Excretion Balance of Gatifloxacin, a New Fluoroquinolone Antibiotic, following Oral Administration to Healthy Caucasian Volunteers

“…Methicillinresistant Staphylococcus aureus strains, which generally are ciprofloxacin resistant, yet were all susceptible to 4 mg/l or less of gatifloxacin. Enterococcus faecalis was two to four times more susceptible to gatifloxacin or trovafloxacin than to ciprofloxacin [3,4]. Gatifloxacin inhibited 90% of the species of the family Enterobacteriaceae at 0.5 mg/l or less with the exception of Enterobacter spp.…”

Antimicrobial activity evaluations of gatifloxacin, a new fluoroquinolone: contemporary pathogen results from a global antimicrobial resistance surveillance program (SENTRY, 1997)

“…Gatifloxacin (AM‐1155 or CG5501) is a new 8‐methoxy fluoroquinolone with demonstrated antibacterial activity against a broad range of Gram‐positive or ‐negative organisms, anaerobes and many fastidious species [1–6]. As a group, the fluoroquinolones inhibit various topoisomerases [7], which prevents bacterial replication at the DNA level.…”

“…Ciprofloxacin, the first used broad‐spectrum fluoroquinolone, remains the leader among the available agents as measured by usage, but the newer fluoroquinolones with expanded Gram‐positive potencies may prove to be valuable in the treatment of some currently refractory pathogens [8–11]. The limitations of ciprofloxacin and ofloxacin (dosing frequency and spectrum) have led to the development of gatifloxacin, trovafloxacin, sitafloxacin (DU‐6859), levofloxacin, and sparfloxacin, each of which can be administered once daily to treat a wider variety of infections [1–6, 9–11]. These infections would include those caused by penicillin‐resistant Streptococcus spp., multiresistant enterococci, oxacillin‐resistant Staphylococcus spp., and some anaerobes [8].…”