Comparative studies of azithromycin in skin and soft-tissue infections and sexually transmitted infections by Neisseria and Chlamydia species.

Two open, randomized, single centre studies have investigated the efficacy and safety of azithromycin (CP-62,993) in the treatment of infections by azithromycin-sensitive pathogens: (A) acute bacterial infections of skin or soft tissue (compared with erythromycin; n = 82); and (B) urethritis and/or cervicitis caused by Neisseria gonorrhoeae and/or Chlamydia trachomatis (compared with doxycycline; n = 108). In study A, azithromycin was administered to 42 patients for five days at a dosage of 250 mg bd on day 1 and 250 mg once daily on days 2-5; erythromycin was given to 40 patients for seven days at a dosage of 500 mg every 6 h. In study B, azithromycin was administered either as a single 1 g dose or as a single 500 mg dose on day 1 and 250 mg once daily on days 2 and 3; doxycycline was given at a dose of 100 mg every 12 h for seven days. In study A, 68 patients were clinically assessed: clinical cure or improvement in patients receiving azithromycin or erythromycin was achieved in 86% and 82%, respectively. The principal causative pathogen was Staphylococcus aureus; there was eradication of 15/25 pathogens (60%) with azithromycin and 13/23 (57%) with erythromycin. In study B, 94 and 93 patients were clinically assessed at weeks 1 and 2, respectively: clinical cure was achieved with all treatment regimens at week 1; at week 2 there was reappearance of symptoms in one patient with a mixed infection who had received 3-day azithromycin.(ABSTRACT TRUNCATED AT 250 WORDS)