Clinical Efficacy of a Single Two Gram Dose of Azithromycin Extended Release for Male Patients with Urethritis

Abstract

To clarify the clinical efficacy of a single oral 2 g dose of azithromycin extended-release for heterosexual male patients with urethritis, and the current antimicrobial sensitivity of Neisseria gonorrhoeae to azithromycin, a prospective clinical trial was conducted from 2011–2013. In patients with gonococcal urethritis, the eradication rate was 90.9% (30 of 33). The susceptibility rates of isolated Neisseria gonorrhoeae strains to ceftriaxone, spectinomycin, cefixime and azithromycin were 100%, 100%, 95.3% (41/43) and 37.2% (16/43), respectively. In the patients with nongonococcal urethritis, the eradication rate was 90.0% (45 of 50). The microbiological eradication rates for the pathogens were 90.9% (30/33) for Neisseria gonorrhoeae, 91.5% (43/47) for Chlamydia trachomatis, 71.4% (5/7) for Mycoplasma genitalium, and 100% (13/13) for Ureaplasma urealyticum. The main adverse event was diarrhea and its manifestation rate was 35.2% (32 of 120). The symptom of diarrhea was mostly temporary and resolved spontaneously. The conclusion was that the treatment regimen with a single oral 2 g dose of azithromycin extended-release would be effective for patients with urethritis. However, the antimicrobial susceptibilities of Neisseria gonorrhoeae and Mycoplasma genitalium should be carefully monitored because of possible treatment failure.

An open label study of the safety and efficacy of a single dose of weekly chloroquine and azithromycin administered for malaria prophylaxis in healthy adults challenged with 7G8 chloroquine-resistant Plasmodium falciparum in a controlled human malaria infection model

“…The overall AE rate, speci cally the GI AE rate, was much higher than most studies that have utilized 2 grams of AZ. Studies to treat male urethritis with a single dose of 2 gm showed GI AE rates around 35% [25,26]. The Zithromax ® drug label cites overall GI rates of around 46% with use of 2 gm.…”

Evaluation of the Microbiological Efficacy of a Single 2-Gram Dose of Extended-Release Azithromycin by Population Pharmacokinetics and Simulation in Japanese Patients with Gonococcal Urethritis

“…In cases in which a single 2-g dose of AZM-SR was used, gastrointestinal symptoms were more likely to occur in Japanese patients (approximately 30%) (13, 14). However, the symptoms were mostly temporary and were resolved within a day when the patients took AZM-SR (13,14). Taken together, when a single 2-g dose of AZM-SR is administered with or without other antibiotics to Japanese patients, the patients should be carefully monitored for gastrointestinal adverse events, particularly within 1 day after AZM-SR administration.…”

“…Although a single 2-g dose of an immediate-release formulation of AZM (conventional AZM) remains effective against uncomplicated gonorrhea (12), this monotherapy could cause an unacceptable rate of adverse events, particularly gastrointestinal upset. Recently, a single 2-g dose of a microsphere-based extended-release formulation of AZM (AZM-SR) was developed and was found to be effective against N. gonorrhoeae (13)(14)(15), and the frequency of adverse events also decreased compared with that achieved with a single 2-g dose of conventional AZM (12,(15)(16)(17)(18). Therefore, a single 2-g dose of AZM-SR is considered useful for the treatment of gonorrhea.…”

Should we still use azithromycin for gonorrhoea treatment?

“…21,22 Dean et al reported poor tolerability in participants receiving a 1 g single dose of azithromycin followed by 500 mg daily for 4 days in a treatment study on Pelvic Inflammatory Disease (PID); 61% of the cohort experienced diarrhoea, of whom nearly 75% described this as being moderate or severe. 23 Interestingly, studies for the treatment of syphilis using a 2 g single dose of azithromycin report lower rates of nausea and diarrhoea (9-13%) 24,25 for reasons that are unclear, but may reflect the subjective nature of reporting side-effects and lack of standardisation.…”