In this randomised, double-blind study carried out in 28 centres,
azithromycin (500 mg single dose on day 1, followed by 250 mg once-daily on days 2-5) was compared with
cefaclor (500 mg t.i.d. for 10 days) in the treatment of acute
bacterial pneumonia. A total of 119 patients entered the study, and of these 71 were evaluable and included in the efficacy analysis. The overall satisfactory clinical response was 97.3% for
azithromycin patients and 100% for
cefaclor patients. The clinical cure rates of
azithromycin and
cefaclor were 46.9% and 41.0%, respectively; improvement was seen in an additional 46.9% of
azithromycin-treated patients and in 59.0% of the
cefaclor group. The bacteriological eradication rates were 80.4% and 92.6%, respectively. These rates of clinical and bacteriological efficacy, were not statistically different. Both
antibiotics were well tolerated during the study; only two patients (one on each study
drug) discontinued medication due to adverse events. The overall incidence of side effects was 18.9% (10 of 53 patients) for
azithromycin- and 12.1% (eight of 66 patients) for
cefaclor-treated patients. Gastrointestinal disturbances were the most commonly reported side effects (nine of 10
azithromycin-treated patients and six of eight
cefaclor-treated patients). In addition, two
cefaclor patients reported
headache. All
azithromycin side effects were mild or moderate in severity, but there were two severe occurrences in the
cefaclor group (1
nausea, 1
vomiting) the later leading to discontinuation.(ABSTRACT TRUNCATED AT 250 WORDS)