Abstract
INTRODUCTION: Trichomonas vaginalis is estimated to be the most common non-viral sexually transmitted infection (STI) worldwide with 156 million new cases each year. In 2021, the United States Centres for Disease Control and Prevention (CDC) updated their STI Treatment Guidelines to recommend multi-dose oral metronidazole (MTZ) for all T. vaginalis-infected women. Although multi-dose oral MTZ 500 mg twice daily was found to be superior to single-dose 2 g oral MTZ in multiple trials in women, multi-dose oral MTZ still had unacceptably high rates of breakthrough infection (9%-11%) at test-of-cure. With approximately 156 million cases of T. vaginalis worldwide per year, over 17 million persons per year are estimated to be insufficiently treated with multi-dose oral MTZ. Moreover, past trials only included women, and single-dose 2 g oral MTZ remains the recommended treatment for men. Thus, there is a critical need to further refine T. vaginalis treatment in women and men. A single dose of 2 g of oral secnidazole (SEC), a next generation 5-nitroimidazole with a longer half-life than oral MTZ and improved tolerability, may be a good option. This study will examine the effectiveness of multi-dose oral MTZ versus single-dose oral SEC in both men and women infected with T. vaginalis. METHODS AND ANALYSIS: This is a multi-centred open-label effectiveness trial comparing oral multi-dose MTZ (500 mg twice daily for 7 days) to 2 g of single-dose oral SEC. This trial aims to enrol 1200 T. vaginalis-infected women and men aged 18 years and older at four clinical sites: the University of Alabama at Birmingham (UAB) Sexual Health Clinic and the UAB Gynaecology Clinics in Birmingham, AL, LSU-CrescentCare Sexual Health Centre (LSUHSC-NO) in New Orleans, LA, and HealthCare Clinical Data, Inc. in Miami, FL. Those who are pregnant/lactating, have been treated with a 5-nitroimidazole within the last 28 days, used intra-vaginal boric acid or any other intra-vaginal treatment for T. vaginalis within the last 14 days, have a history of a type 1 hypersensitivity reaction to 5-nitroimidazoles, are taking phenytoin and/or warfarin, use any medications which may alter the metabolism of oral MTZ, or have previously been enrolled will be excluded from the study. Participants will be randomised in a 1:1 fashion to either multi-dose oral MTZ or single-dose oral SEC. A test-of-cure (TOC) visit will be performed 4 weeks after completion of treatment (window 1 week before and 2 weeks after scheduled TOC visit). ETHICS AND DISSEMINATION: This protocol is approved through a single Institutional Review Board (IRB) mechanism by the Tulane Human Research Protection Programme (Protocol # 2024-101 SPHTM). External relying sites are the UAB IRB (including both the UAB Sexual Health Research Clinic and Gynaecology Clinics; Protocol ID IRB-300012617), the LSUHSC-NO IRB (LSU-CrescentCare Sexual Health Centre; Protocol ID 6979) and the Advarra IRB (Healthcare Clinical Data Inc; Protocol ID Pro00085531). This study is also approved for referral purposes only by the Research Review Committee at the Jefferson County Department of Health (JCDH) Sexual Health Clinic in Birmingham, AL (JCDH Research Number 2024-03). Study findings will be presented in scientific conferences and peer-reviewed journals, shared with treatment advisory boards, as well as disseminated to providers and patients in communities of interest. The study Data Safety and Monitoring Board (DSMB) will meet twice a year to review patient safety data and study progress and provide recommendations on the study's continuation or modification. TRIAL REGISTRATION NUMBER: NCT06261840.