Roxithromycin Compared to Doxycycline in the Treatment of Genital Chlamydial Infection and Non-Specific Urethritis

Abstract

A single-blind randomized follow-up study was conducted to evaluate the efficacy and tolerance of roxithromycin 300 mg once a day compared to doxycycline 200 mg day 1 and 100 mg day 2–10 in the treatment of genital chlamydial infection in men and women and non-specific urethritis (NSU) in men. A total of 211 patients (200 men and 11 women) between 18 and 46 years were enrolled. The women were excluded from the efficacy analysis because of the low number, but were included in the tolerance analysis. The clinical (clearance of polymorphonuclear leucocytes in urethral smears) and bacteriological response was evaluated one and 11 days after the treatment. Of 113 included men with chlamydial infection, 105 (93%) and 96 (85%) were evaluable on respective follow-up visits and of 87 included men with NSU, 74 (85%) and 64 (74%) were evaluable one and 11 days after treatment, respectively. The bacteriological eradication rate immediately after the treatment in chlamydia positive patients was 92.7% and 100% for roxithromycin and doxycycline, respectively, and 91.8% and 100% at follow-up. The clinical cure rate of all evaluable patients was 83.1% and 80.7% for roxithromycin and doxycycline, respectively, one day after the treatment and 80.5% and 85.3% for the two drugs, respectively, 11 days after treatment. None of these observed differences was statistically significant. The diagnosis did not influence the clinical response rate with either drug. Probable and possible drug-related side-effects were more common after doxycycline than after roxithromycin, 35% and 19% respectively (P = 0.0032). The side effects were mainly mild gastro-intestinal symptoms with short duration and none of the patients receiving roxithromycin stopped the treatment. Roxithromycin, belonging to a new generation of macrolides related to erythromycin, can be given as an effective single daily dose of 300 mg for 10 days to cure genital chlamydial infection and NSU in men, and its efficacy is comparable with that of doxycycline in standard recommended dose. Roxithromycin was shown to be safe and it had fewer and milder side-effects than doxycycline.