Ac. Gales et Rn. Jones, Antimicrobial activity and spectrum of the new glycylcycline, GAR-936 tested against 1,203 recent clinical bacterial isolates, DIAG MICR I, 36(1), 2000, pp. 19-36
The in vitro activity of GAR-936, a new semisynthetic glycylcycline, was ev
aluated in comparison with two tetracyclines and several other antimicrobia
l agents. A total of 1, 203 recent clinical isolates were tested by referen
ce broth or agar dilution methods. Among the members of the family Enteroba
cteriaceae, GAR-936 was generally two- to four-fold more active than minocy
cline, and two- to 16-fold more active than tetracycline. All enteric bacil
li MIC90 results were less than or equal to 4 mu g/mL; the exception being
Proteus mirabilis and indole-positive Proteae (greater than or equal to 8 m
u g/mL). GAR-936 demonstrated excellent activity against all Gram-positive
cocci with 90% of the penicillin-resistant Streptococcus pneumoniae isolate
s inhibited at 0.03 mu g/ml, while the same isolates had a MIC90 of 8 and >
8 mu g/mL for minocycline and tetracycline, respectively. All Enterococcus
spp., including vancomycin-resistant isolates, were inhibited at 0.25 mu g
/mL of GAR-936 (MIC90, 0.12 or 0.25 mu g/mL). Although GAR-936 (MIC50, 0.25
mu g/mL) was two-fold less active than minocycline (MIC50, 0.12 mu g/mL) a
gainst oxacillin-resistant Staphylococcus aureus, all isolates were inhibit
ed at less than or equal to 0.25 mu g/mL. GAR-936 demonstrated good activit
y against nonfermentative bacteria such as Acinetobacter spp. (MIC90, mu g/
ml) and Stenotrophomonas maltophilia (MIC90, 4 mu g/mL), but the compound e
xhibited only modest activity against Pseudomonas aeruginosa (MIC50, 8 mu g
/mL). Haemophilus influenzae (MIC90, 1-2 mu g/mL), Moraxella catarrhalis (M
IC90, 0.12 mu g/mL), and various Neisseria spp. (MIC90, 0.12-0.5 mu g/mL) w
ere susceptible to GAR-936. These results indicate that GAR-936 has potent
in vitro activity against a wide range of clinically important pathogenic b
acteria, and that several Gram-positive and -negative isolates resistant to
older tetracyclines and other drug classes remain susceptible to GAR-936,
the newest glycylcycline candidate for clinical use. (C) 2000 Elsevier Scie
nce Inc. All rights reserved.