IN-VITRO ACTIVITY OF THE NEW KETOLIDE HMR-3004 COMPARED TO AN AZALIDEAND MACROLIDES AGAINST STREPTOCOCCUS-PNEUMONIAE AND HAEMOPHILUS-INFLUENZAE

The purpose of this study was to compare the in vitro activity of a ne w ketolide, HMR 3004 (RU64004), to that of three macrolides and one az alide against 608 Streptococcus pneumoniae and 202 Haemophilus influen zae. Macrolide-resistant pneumococci were susceptible to HMR 3004, eve n if they were resistant to clindamycin, Against Haemophilus influenza e, HMR 3004 and azithromycin were nearly identical in potency; the mac rolides were 8- to 16-fold less active, HMR 3004 may be useful for tre ating respiratory tract infections if sufficient concentrations can be achieved at the local sites of infection.