Secnidazole: a treatment for trichomoniasis in adolescents and adults

Abstract

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.

Keywords: 5-nitroimidazoles; Trichomonas vaginalis; Trichomoniasis; metronidazole; secnidazole; sexually transmitted infections; tinidazole.

Figure 1.

Chemical structure of secnidazole, metronidazole, and tinidazole

Figure 2.

A single 2-g oral dose of secnidazole reaches peak plasma concentrations at 4 hours, and with its long half-life, remains above the minimum inhibitory concentration for several days as opposed to oral metronidazole 500 mg, which requires repeat dosing. (Adapted from Lupin Pharmaceuticals [data on file] and Ashiq B, et al. 2011 [78].