Study objectives: To compare the efficacies of 10-day
regimens of grepafloxacin (GFX) (Raxar or Vaxar; Glaxo Wellcome;
Greenford, UK), 600 qd, and clarithromycin (CLA) (Klacid, Biaxin, or
Klaracid; Abbott Laboratories; Chicago, IL), 500 mg bid, in patients
with community-acquired pneumonia (CAP), on the basis of clinical
response, including radiographic evidence, and bacteriologic
Design: Phase IIIb, double-blind,
double-dummy, randomized, prospective, parallel-group, comparative
study conducted at 58 centers in 11 countries.
setting: Adult patients with signs and symptoms of CAP that was
confirmed by radiographic evidence and who did not require parenteral
therapy were included in the study.
Patients were assessed before treatment, during treatment, after
treatment, and at follow-up (28 to 35 days after treatment completion).
Clinical response was evaluated. Blood and sputum samples were cultured
for bacterial pathogens, and serology testing was performed to detect
Results: A total of 504 patients
were enrolled into the trial: 251 were randomly assigned to receive GFX
and 253 to receive CLA. In patients able to be clinically evaluated,
clinical success rates at follow-up were 147 of 163 patients (90%) in
the GFX group and 148 of 167 patients (89%) in the CLA group (95%
confidence interval, −6% to 9%). Pretreatment pathogens were
confirmed in 131 of 504 patients (26%), either by culture or serology
testing, the primary pathogens being Streptococcus
pneumoniae (22%), Haemophilus influenzae
(17%), Mycoplasma pneumoniae (25%), and
Chlamydia pneumoniae (11%). For patients able to be
evaluated who had typical pathogens, bacteriologic success was achieved
in 92% of the patients in each treatment group. For patients able to
be evaluated who had atypical pathogens, 18 of 18 patients (100%) in
the GFX and 23 of 26 patients (88%) in the CLA group had a successful
clinical outcome. There were similar rates of adverse events in each
group, resulting in ≤ 7% withdrawal from treatment; gastrointestinal
events were the most common.
Conclusions: GFX, 600 mg
qd, was equivalent to CLA, 500 mg bid, in treating adult patients with
CAP. Both treatments were well tolerated.