A double-blind controlled clinical trial of carnidazole and tinidazole in the treatment of vaginal trichomoniasis

Secnidazole: a treatment for trichomoniasis in adolescents and adults

INTRODUCTION

Single-dose 2-g oral secnidazole (SEC), newly approved by the U.S. Food and Drug administration (FDA) for treatment of trichomoniasis, is a potent 5-nitroimidazole with selective toxicity against various micro-organisms. It has been used internationally to treat trichomoniasis, bacterial vaginosis, and other infections for decades. Trichomoniasis is the most common non-viral sexually transmitted infection worldwide and is associated with significant morbidity. In comparison to the only other FDA-approved treatments for trichomoniasis in the United States - metronidazole and tinidazole - SEC has favorable pharmacokinetics, including a longer half-life and a lower minimal lethal concentration.

AREAS COVERED

This work summarizes the chemistry and pharmacology of SEC and reviews the evidence on its efficacy, tolerability, and safety for the treatment of trichomoniasis.

EXPERT OPINION

SEC is an efficacious, well tolerated, and safe treatment for patients aged ≥12 years with trichomoniasis. Single-dose administration makes it a favorable treatment option, especially in cases where adherence to multi-dose treatment regimens may be low.

Interventions for treating trichomoniasis in women

OBJECTIVES

Around 120 million women worldwide suffer from Trichomonas vaginalis vaginitis every year. The infection is sexually transmitted and is believed to facilitate HIV transmission. The objective of the review is to assess the effects of various treatment strategies for trichomoniasis in women.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register, MEDLINE, and EMBASE. Trials were also identified from reference lists of reviews, through pharmaceutical companies, and by informal discovery. Only published data were used in this review. Date of the most recent search: May, 1999.

SELECTION CRITERIA

Randomized or quasi-randomized trials in women with trichomoniasis of different treatment strategies, different antitrichomonal drugs or doses were eligible.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed and data extracted by two reviewers independently using standard criteria.

MAIN RESULTS

Fifty-two trials were included. Nitroimidazoles seem to be effective in achieving parasitological cure in the short term follow-ups. Partner treatment can be effective in decreasing longer term re-infection rates.

REVIEWER'S CONCLUSIONS

Parasitological cure can be achieved by single oral dose of nitroimidazoles. Further research should focus on developing effective partner treatment strategies to prevent re-infections and reduce trichomoniasis prevalence.

Clinical and microbiological aspects of Trichomonas vaginalis

Trichomonas vaginalis, a parasitic protozoan, is the etiologic agent of trichomoniasis, a sexually transmitted disease (STD) of worldwide importance. Trichomoniasis is the most common nonviral STD, and it is associated with many perinatal complications, male and female genitourinary tract infections, and an increased incidence of HIV transmission. Diagnosis is difficult, since the symptoms of trichomoniasis mimic those of other STDs and detection methods lack precision. Although current treatment protocols involving nitroimidazoles are curative, metronidazole resistance is on the rise, outlining the need for research into alternative antibiotics. Vaccine development has been limited by a lack of understanding of the role of the host immune response to T. vaginalis infection. The lack of a good animal model has made it difficult to conduct standardized studies in drug and vaccine development and pathogenesis. Current work on pathogenesis has focused on the host-parasite relationship, in particular the initial events required to establish infection. These studies have illustrated that the pathogenesis of T. vaginalis is indeed very complex and involves adhesion, hemolysis, and soluble factors such as cysteine proteinases and cell-detaching factor. T. vaginalis interaction with the members of the resident vaginal flora, an advanced immune evasion strategy, and certain stress responses enable the organism to survive in its changing environment. Clearly, further research and collaboration will help elucidate these pathogenic mechanisms, and with better knowledge will come improved disease control.

Single dose treatment of trichomoniasis

Oral treatment for trichomonas vaginalis infection is now well established. In a previous paper, we established the value of a high single dose regimen of metronidazole for this condition by demonstrating its efficacy in a double-blind controlled study. Tinidazole is another accepted trichomonacide. By means of a single-blind controlled trial, we demonstrate that a 2 g single dose of tinidazole is as effective as a 2 g single dose metronidazole in the treatment of vaginal trichomoniasis. The cure rate for tinidazole was 95% and for metronidazole it was 97.5%. No side-effects were reported with either regimen.