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Published on: October 23, 2013
Azithromycin or Doxycycline for Asymptomatic Rectal Chlamydia trachomatis.
Andrew Lau1, Fabian Y S Kong1, Christopher K Fairley1
1From the University of Melbourne (A.L., F.Y.S.K., S.P., E.P.F.C., N.C., J.S.H.), the Melbourne Sexual Health Centre (C.K.F., M.Y.C., C.S.B., E.P.F.C., J.S.H.), and Monash University (C.K.F., M.Y.C., C.S.B., E.P.F.C.), Melbourne, VIC, Macquarie University, Macquarie, NSW (J.A.), Central Clinical School, Faculty of Medicine and Health, University of Sydney (D.J.T.), Sydney Sexual Health Centre (A.M., B.D.), and the School of Population Health (A.M.) and the Kirby Institute (D.J.T., M.L., B.D., D.G.R., J.K., J.A.), University of New South Wales, Sydney, the Department of Sexual Health Medicine and Sexual Assault Medicine, Sydney Local Health District, Camperdown, NSW (D.J.T.), Western Sydney Sexual Health Centre, Parramatta, NSW, and Westmead Clinical School, University of Sydney, Westmead, NSW (D.A.L.), the Adelaide Sexual Health Centre (C.K., M.R.) and the University of Adelaide (M.A.B.), Adelaide, SA, and the University of the Sunshine Coast, Sippy Downs, QLD (P.T.) - all in Australia.
Doxycycline for 7 days achieved higher cure rates for rectal chlamydia in men who have sex with men compared to a single dose of azithromycin. This study provides crucial data for treating this common sexually transmitted infection.
Area of Science:
- Infectious Diseases
- Public Health
- Clinical Trials
Background:
- Rectal chlamydia is a prevalent bacterial sexually transmitted infection (STI) primarily affecting men who have sex with men (MSM).
- Current treatment guidelines require more evidence from randomized controlled trials to effectively manage rectal chlamydia infections.
- A significant majority of individuals with rectal chlamydia are asymptomatic, necessitating specific research into effective treatment strategies for this population.
Purpose of the Study:
- To compare the efficacy of a 7-day course of doxycycline versus a single dose of azithromycin for treating asymptomatic rectal chlamydia in MSM.
- To provide robust data from a randomized controlled trial to inform clinical guidelines for rectal chlamydia treatment.
Main Methods:
- A double-blind, randomized controlled trial was conducted across five sexual health clinics in Australia.
- Participants included MSM diagnosed with asymptomatic rectal chlamydia, randomly assigned to receive either doxycycline (100 mg twice daily for 7 days) or azithromycin (1-g single dose).
- The primary outcome measured was microbiologic cure, confirmed by a negative nucleic acid amplification test for rectal chlamydia at 4 weeks post-treatment.
Main Results:
- The study enrolled 625 MSM between August 2016 and August 2019.
- Microbiologic cure rates were significantly higher in the doxycycline group (96.9%) compared to the azithromycin group (76.4%), with an adjusted risk difference of 19.9 percentage points (P<0.001).
- Adverse events were reported more frequently in the azithromycin group (45.1%) than in the doxycycline group (33.8%).
Conclusions:
- A 7-day course of doxycycline is a more effective treatment for rectal chlamydia in MSM than a single dose of azithromycin.
- These findings support doxycycline as a preferred regimen for rectal chlamydia treatment in this population.
- The study underscores the need for evidence-based treatment strategies for STIs in MSM.
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