Solosec (secnidazole) - 2 indications

Scroll down for information on each indication:

• for the treatment of bacterial vaginosis; approved September 2017
• for the treatment of trichomoniasis in adults; approved July 2021

General Information

Solosec (secnidazole) is a nitroimidazole antimicrobial.

Solosec is specifically indicated for the treatment of bacterial vaginosis in adult women and for the treatment of Trichomoniasis vaginalis.

Solosec is supplied as oral granules. The recommended dosage of Solosec is a single 2-gram packet of granules taken once orally, without regard to the timing of meals. Open the Solosec packet by folding over the corner (marked by an arrow) and tearing across the top. Sprinkle the entire contents of the packet onto applesauce, yogurt or pudding. The granules will not dissolve. Consume all of the mixture within 30 minutes without chewing or crunching the granules. A glass of water may be taken after the administration of Solosec to aid in swallowing. The granules are not intended to be dissolved in any liquid. 

Mechanism of Action

Solosec (secnidazole) is a 5-nitroimidazole antimicrobial. 5-nitroimidazoles enter the bacterial cell as an inactive prodrug where the nitro group is reduced by bacterial enzymes to radical anions. It is believed that these radical anions interfere with bacterial DNA synthesis of susceptible isolates. 

Side Effects

Adverse effects associated with the use of Solosec for BV may include, but are not limited to, the following:

• vulvo-vaginal candidiasis
• headache
• nausea
• dysgeusia
• vomiting
• diarrhea
• abdominal pain
• vulvovaginal pruritus

Most common adverse reaction observed in the clinical trial of trichomoniasis (incidence ≥ 2%) was vulvovaginal candidiasis

Indication 1 - for the treatment of bacterial vaginosis

approved September 2017

Clinical Trial Results

The FDA approval of Solosec for BV was based on two randomized placebo-controlled clinical trials (Trial 1 and Trial 2) with similar designs were conducted to evaluate the efficacy of Solosec 2 gram for the treatment of bacterial vaginosis. Trial 1 enrolled 144 non-pregnant female patients aged 19 to 54 years and Trial 2 enrolled 189 non-pregnant females aged 18 to 54 years. Efficacy was assessed by clinical outcome evaluated 21 to 30 days following a single dose of Solosec. A Clinical responder was defined as “normal” vaginal discharge, negative “whiff” test, and clue cells <20%. In both trials, a statistically significantly greater percentage of patients experienced clinical response at 21 to 30 days following a single dose of Solosec compared to placebo: Trial 1: 67.7% vs. 17.7% and Trial 2: 53.3% vs. 19.3%.  Statistically significant results for the endpoints were also achieved at Day 7-14 in Trial 2. 

Indication 2 - for the treatment of trichomoniasis in adults

approved July 2021

Clinical Trial Results

The FDA approval of Solosec for trichomoniasis was based on a multi-center, prospective, randomized, placebo-controlled, delayed treatment, double-blind, trial. A total of 147 female patients from the United States aged 15 to 65 years were enrolled and randomized 1:1 to receive either Solosec or placebo. The modified intent-to-treat (mITT) population included all randomized patients who were culture positive for T. vaginalis and negative for other sexually transmitted infections. Microbiological cure was reached in 92.2% of treated patients versus 1.5% of placebo treated patients. 

The single oral 2 g secnidazole dose was also assessed in four open-label trials: one comparative study with metronidazole and ornidazole in males only and three single-arm studies in males and females. Parasitological evaluation was performed both pre- and post-treatment and reported cure rates ranged from 91.7% (165/180) to 100% (30/30) at time points ranging from 2 to 20 days (n=437, 211 males and 226 females). In addition, the natural history of trichomoniasis in men was evaluated in one study. The spontaneous resolution during a mean follow-up of 16 ± 12 days was noted in 36% of untreated men.