Lack of a Pharmacokinetic Interaction Between SYM-1219 Granules Containing 2 Grams of Secnidazole and a Combined Oral Contraceptive in a Phase 1, Randomized, Open-Label Study in Healthy Female Volunteers

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.

In vitro metabolic profile and drug-drug interaction assessment of secnidazole, a high-dose 5-nitroimidazole antibiotic for the treatment of bacterial vaginosis

A single-dose oral granule formulation of secnidazole 2 g (SOLOSEC™ ) has been approved in the US as a treatment for bacterial vaginosis. Available data on the likelihood of in vitro drug-drug and alcohol-drug interactions are limited. Secnidazole was incubated with cultured human hepatocytes over a range of concentrations (0-10 000 μmol/L) to assess metabolic profiling. Cytochrome P450 (CYP) and aldehyde dehydrogenase inhibition over a similar concentration range were evaluated in human liver microsomes (HLMs) or recombinant enzymes using competition or time-dependent inactivation assays. Secnidazole exhibited very low metabolism in HLMs at concentrations up to 6400 µmol/L. Secnidazole was found to be metabolized to a limited extent predominantly by CYP3A4 and CYP3A5 among a panel of cDNA-expressed enzymes. Secnidazole inhibited CYP2C19 and CYP3A4, with IC50 values of 3873 and 3722 µmol/L, respectively. Secnidazole did not exhibit time-dependent inhibition. There was no inhibition (IC50 value >5000 µmol/L) observed for any other CYP enzyme or with human recombinant aldehyde dehydrogenase 2 (ALDH2). These results are the first reported observation of the metabolism and drug-drug interaction profile for secnidazole and demonstrate that the agent has minimal to no potential drug interactions of concern.

Efficacy and safety of single dose of oral secnidazole 2 g in treatment of bacterial vaginosis: A systematic review and meta-analysis

BACKGROUND

Bacterial vaginosis (BV) is a common disease characterized by vaginal discharge.

OBJECTIVE

To evaluate the evidence from published randomized clinical trials (RCTs) about the efficacy and safety of single dose of oral secnidazole 2 g in comparison with other drugs.

SEARCH STRATEGY

Electronic databases were searched using the following MeSH terms (bacterial vaginosis OR vaginosis) AND (secnidazole OR secnol OR sabima OR secnidal OR minovage).

SELECTION CRITERIA

All RCTs assessing effect of secnidazole in treatment of BV were considered for this meta-analysis. Two-hundred thirty two studies were identified of which six studies were deemed eligible for this review.

DATA COLLECTION AND ANALYSIS

The extracted data were entered into RevMan software. The relative risk (RR) and 95% confidence interval (CI) were calculated. The extracted outcomes were the clinical cure and adverse effects.

MAIN RESULTS

The pooled estimate showed that ornidazole is superior to a single dose of oral secnidazole in clinical cure at the 4th week after treatment (RR = 0.81; 95% CI [0.73- 0.89], p < 0.0001, I² = 0%). There were no difference between secnidazole and metronidazole (RR = 0.97; 95% CI [0.90-1.05], I² = 0%, p = 0.5).

CONCLUSIONS

Single oral dose of secnidazole 2 g doesn't differ from metronidazole regimen however, it may be inferior to ornidazole in treatment of BV.

Secnidazole: next-generation antimicrobial agent for bacterial vaginosis treatment

Secnidazole is a next-generation 5-nitroimidazole approved for more than three decades in Europe, Asia, South America and Africa and recently in the USA as a single-dose (2 g) treatment of bacterial vaginosis (BV). Secnidazole is characterized by potent in vitro antimicrobial activity against BV-associated pathogens, as well as prolonged terminal elimination half-life and systemic exposure. These characteristics form the basis of effective and safe treatment of BV with a 2-g single-dose secnidazole regimen, which was recently confirmed in double-blind, placebo-controlled clinical trials conducted in the USA. The option to treat BV with single-dose secnidazole not only cures the primary infection but also may diminish risks of serious sequelae of untreated or undertreated infection.

A phase-3, double-blind, placebo-controlled study of the effectiveness and safety of single oral doses of secnidazole 2 g for the treatment of women with bacterial vaginosis

BACKGROUND

A novel single oral dose granule formulation of secnidazole 2 g, a 5-nitroimidazole with a longer half-life (∼17 hours) than metronidazole (∼8 hours), is being developed to treat bacterial vaginosis.

OBJECTIVE

We sought to evaluate the effectiveness and safety of single-dose secnidazole 2 g compared to placebo for the treatment of women with bacterial vaginosis.

STUDY DESIGN

In all, 189 women with bacterial vaginosis were randomized 2:1 to receive a single oral dose of secnidazole 2 g (N = 125) or matched placebo (N = 64) at 21 centers in the United States. The primary endpoint was the proportion of clinical outcome responders, defined as those with: (1) normal vaginal discharge; (2) negative 10% potassium hydroxide whiff test; and (3) <20% clue cells of total epithelial cell count on microscopic examination of the vaginal wet mount, using saline at the test of cure/end of study visit (study days 21-30). Secondary efficacy analyses included clinical cure rates, defined as: (1) responders with normal vaginal discharge; (2) negative potassium hydroxide whiff tests; and (3) clue cells <20% assessed at the interim visit (study days 7-14), and test of cure/end of study (study days 21-30). In addition, based on the 2016 US Food and Drug Administration draft guidance, patients with baseline Nugent scores 7-10 were evaluated for clinical cure using the following clinical assessments on study days 7-14: (1) resolution of the abnormal vaginal discharge; (2) a negative potassium hydroxide whiff test; and (3) clue cells <20%. The study was designed and powered to demonstrate the efficacy of single-dose secnidazole 2 g compared to placebo; safety and tolerability were also assessed. Due to a prespecified institutional review board-approved protocol calling for withdrawal of randomized, treated patients with a Nugent score <4 or with a separate sexually transmitted infection, this modified intent-to-treat population was the primary analysis population. Statistical comparisons used a stratified Cochran-Mantel-Haenszel test with a .05 level of significance (2-sided).

RESULTS

Single-dose secnidazole 2 g was superior to placebo for the primary and all secondary efficacy measures in the modified intent-to-treat population, with clinical outcome responder rates of 53.3% (57/107) vs 19.3% (11/57; P < .001). Clinical cure rates, based on an alternate definition of responder, which accounted for resolution of abnormal discharge consistent with bacterial vaginosis, were consistent with the clinical outcome responder rate analysis (58.9% vs 24.6%; P < .001) for single-dose secnidazole 2 g vs placebo. Clinical cure rates based on the 2016 US Food and Drug Administration guidance were 64.0% vs 26.4% for single-dose secnidazole 2 g vs placebo. Based on the investigator's clinical assessment at the test of cure/end of study visit, significantly more patients receiving single-dose secnidazole 2 g vs placebo required no additional bacterial vaginosis treatment (68.0% [68/100] vs 29.6% [16/54]; P < .001). Adverse events considered by the investigator to be related to study drug occurred in only 20.0% of single-dose secnidazole 2 g-treated patients vs 10.9% of placebo patients, and they included diarrhea (4.0% vs 1.6%), headache (4.0% vs 3.1%), nausea (4.8% vs 1.6%), and vulvovaginal candidiasis (4.0% vs 3.1%).

CONCLUSION

Single-dose secnidazole 2 g was superior to placebo on all primary and secondary outcomes and was well tolerated; these results support its role for the treatment of women with bacterial vaginosis.

Two Phase 1, Open-Label, Single-Dose, Randomized, Crossover Studies to Assess the Pharmacokinetics, Safety, and Tolerability of Orally Administered Granules of Secnidazole (2 g) in Healthy Female Volunteers Under Different Administration Conditions

Bacterial vaginosis (BV) is the most common vaginal infection in reproductive-age women and a significant risk factor for sexually transmitted diseases and pregnancy complications. Standard 5- to 7-day antimicrobial treatments for BV are associated with high rates of recurrence and adverse events. SYM-1219 is a novel granule formulation containing 2 g of secnidazole, developed as an oral, single-dose BV treatment. Two phase 1, open-label, single-center, randomized, crossover trials (studies 102 and 103) assessed the pharmacokinetics and safety of SYM-1219 single doses (≥7-day washout between doses) in healthy, nonpregnant women aged 18 to 65 years inclusive. Study 102 compared SYM-1219 in applesauce in fasted vs fed states. Study 103 compared SYM-1219 (fasted) in pudding and yogurt vs applesauce. Studies 102 and 103 each dosed 24 subjects (mean [standard deviation] ages, 36 [1.8] and 40 [11.6] years, respectively). In both studies the 90% confidence intervals for all treatment comparisons of maximum plasma concentration, area under the concentration-time curve from 0 to last measurable concentration and to infinity, geometric mean ratios were within 80% to 125%, demonstrating bioequivalence. In both studies median fasted time to maximum plasma concentration was 4 hours (6 hours fed in study 102), and mean half-life ranged from 17 to 19 hours. Treatment-emergent adverse events occurred in 70.8% and 83.3% subjects in studies 102 and 103, respectively, most commonly headache (41.7% and 50.0%) and gastrointestinal treatment-emergent adverse events. The pharmacokinetics of SYM-1219 were similar in fed and fasted states and when administered in different foods.

Nitroimidazoles: Molecular Fireworks That Combat a Broad Spectrum of Infectious Diseases

Infectious diseases claim millions of lives every year, but with the advent of drug resistance, therapeutic options to treat infections are inadequate. There is now an urgent need to develop new and effective treatments. Nitroimidazoles are a class of antimicrobial drugs that have remarkable broad spectrum activity against parasites, mycobacteria, and anaerobic Gram-positive and Gram-negative bacteria. While nitroimidazoles were discovered in the 1950s, there has been renewed interest in their therapeutic potential, particularly for the treatment of parasitic infections and tuberculosis. In this review, we summarize different classes of nitroimidazoles that have been described in the literature in the past five years, from approved drugs and clinical candidates to examples undergoing preclinical or early stage development. The relatively "nonspecific" mode of action and resistance mechanisms of nitromidazoles are discussed, and contemporary strategies to facilitate nitroimidazole drug development are highlighted.