Warnings for Nuvessa
Included as part of the PRECAUTIONS section.
Precautions for Nuvessa
Central And Peripheral Nervous System Effects
Convulsive seizures, encephalopathy, aseptic meningitis, optic and peripheral neuropathy, the latter characterized mainly by numbness or paresthesia of an extremity, have been reported in patients treated with oral or intravenous metronidazole. NUVESSA should be administered with caution to patients with central nervous system diseases. Discontinue promptly if abnormal neurologic signs develop.
Carcinogenicity in Animals
Metronidazole has been shown to be carcinogenic at high doses administered orally in mice and rats [see Nonclinical Toxicology]. Unnecessary use of metronidazole should be avoided. Use of NUVESSA should be reserved for the treatment of bacterial vaginosis [see INDICATIONS AND USAGE].
Drug/Laboratory Test Interactions
Metronidazole may interfere with certain types of determinations of serum chemistry values, such as aspartate aminotransferase (AST, SGOT), alanine aminotransferase (ALT, SGPT), lactate dehydrogenase (LDH), triglycerides, and glucose hexokinase. Values of zero may be observed. All of the assays in which interference has been reported involve enzymatic coupling of the assay to oxidation reduction of nicotinamide-adenine dinucleotides (NAD + NADH). Interference is due to the similarity in absorbance peaks of NADH (340 nm) and metronidazole (322 nm) at pH 7.
Patient Counseling Information
Advise the patient to read the FDA-approved patient labeling (PATIENT INFORMATION and Instructions for Use).
Interaction With Alcohol
Instruct the patient not to consume alcoholic beverages and preparations containing ethanol or propylene glycol during and for at least 24 hours after treatment with NUVESSA [see CONTRAINDICATIONS and DRUG INTERACTIONS].
Drug Interactions
Instruct the patient not to use NUVESSA if disulfiram had been used within the last two weeks [see CONTRAINDICATIONS], and to inform their healthcare provider if they are taking oral anticoagulants, or lithium [see DRUG INTERACTIONS].
Vaginal Intercourse And Use With Vaginal Products
Instruct the patient not to engage in vaginal intercourse, or use other vaginal products (such as tampons or douches) following the single administration of NUVESSA.
Lactation
A patient may choose to pump and discard breastmilk during treatment with NUVESSA and for 48 hours after last dose, and feed her infant previously stored human milk or formula [see Use In Specific Populations].
Vaginal Irritation
Inform the patient to discontinue use and consult a healthcare provider if vaginal irritation occurs with use of NUVESSA.
Administration Of Drug
Instruct the patient that NUVESSA is supplied as a single dose in a pre-filled applicator.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Metronidazole has shown evidence of carcinogenic activity in a number of studies involving chronic oral administration in mice and rats. Pulmonary tumors were reported in several mouse studies in which mice were dosed orally at 75 mg/kg and above (about 6 or more times the maximum recommended human dose based on mg/m²). Malignant lymphoma was reported at 66 mg/kg and above (about 5 or more times the maximum recommended human dose based on mg/m²). These tumors have been observed in all six reported studies in the mouse, including one study in which the animals were dosed on an intermittent schedule (administration during every fourth week only). All these effects were statistically significant.
There were statistically significant increases in the incidence of mammary tumors, among female rats administered metronidazole at 270 mg/kg and above (about 40 times the maximum human dose based on mg/m²). Hepatic adenomas and carcinomas were observed in rats administered 300 mg/kg (about 45 times the maximum human dose based on mg/m²).
Two lifetime oral tumorigenicity studies in hamsters have been performed and reported to be negative at doses up to 80 mg/kg (about 10 times the maximum human dose based on mg/m²).
Carcinogenesis studies have not been conducted with NUVESSA.
Although metronidazole has shown in vitro mutagenic activity in bacterial reverse mutation tests, it was negative in in vitro mammalian mutation systems including CHO/HGPRT and CH V79 lung cell assays. Metronidazole was not clastogenic in vitro chromosome aberration tests in CHO cells up to 5000 μg/mL but was positive in human and monkey peripheral blood lymphocytes at 0.1 μg/mL.
In general, numerous micronucleus studies in rats and mice have failed to demonstrate a potential for genetic damage up to single oral doses 3000 mg/kg in mice (about 225 times the maximum human dose based on mg/m²). However, a dose dependent increase in the frequency of micronuclei was observed in CFW mice after intraperitoneal injections of up to 160 mg/kg (about 12 times the maximum human dose based on mg/m²).
Fertility studies have been performed in mice orally dosed up to 500 mg/kg (about 37 times the maximum human dose based on mg/m²) revealed no evidence of impaired fertility.
While no effects on fertility were observed in female rats dosed intraperitoneally at doses up to 1000 mg/kg (about 300 times the maximum human dose based on mg/m²), studies in male rats resulted in effects on testes and sperm production at oral doses of 100 mg/kg and above (about 30 times the maximum human dose based on mg/m²).
Use In Specific Populations
Pregnancy
Risk Summary
There are no data available on the use of NUVESSA in pregnant women. Metronidazole usage in pregnancy has been associated with certain congenital anomalies (see Data). In animal reproduction studies, no fetotoxicity or teratogenicity was observed when metronidazole was administered orally to pregnant rats and rabbits, during organogenesis, at up to 30 times and 60 times the recommended human dose based on body surface area comparison, respectively (see Data).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.
Data
Human Data
Blood levels following NUVESSA vaginal administration are lower than those achieved with oral metronidazole. Following a single intravaginal 5 g dose of NUVESSA, mean maximum concentration (Cmax) and total exposure (AUC0-∞) are approximately 2% and 4%, respectively, of those following a single oral 500 mg dose of metronidazole tablets [see CLINICAL PHARMACOLOGY]. Metronidazole crosses the placental barrier and enters the fetal circulation rapidly.
There are published data from case-control studies, cohort studies, and 2 meta-analyses that include more than 5000 pregnant women who used metronidazole during pregnancy. Many studies included first trimester exposures. One study showed an increased risk of cleft lip, with or without cleft palate, in infants exposed to metronidazole in utero; however, these findings were not confirmed.
In addition, more than ten randomized placebo-controlled clinical trials enrolled more than 5000 pregnant women to assess the use of antibiotic treatment (including metronidazole) for bacterial vaginosis on the incidence of preterm delivery. Most studies did not show an increased risk for congenital anomalies or other adverse fetal outcomes following metronidazole exposure during pregnancy.
Three studies conducted to assess the risk of infant cancer following metronidazole exposure during pregnancy did not show an increased risk; however, the ability of these studies to detect such a signal was limited.
Animal Data
No fetotoxicity or teratogenicity was observed when metronidazole was administered orally to pregnant rabbits at up to 200 mg/kg (about 60 times the maximum human dose based on body surface area comparison). Similarly, no fetotoxic or teratogenic effects were observed in five studies in rats where dosing was administered orally in the diet or by gastric intubation at doses up to 200 mg/kg (about 30 times the maximum human dose based on body surface area comparison).
As well, no fetotoxicity or teratogenicity was observed when metronidazole was administered orally to pregnant mice at doses up to 100 mg/kg (about 7 times the maximum human dose based on body surface area comparison). However, some intrauterine deaths were observed in Swiss Webster mice administered metronidazole intraperitoneally at doses up to 15 mg/kg (about 1 times the maximum human dose based on body surface area comparison). The relationship of these intraperitoneal findings in mice to the vaginal use of NUVESSA is unknown.
Lactation
Risk Summary
There are no data on the presence of metronidazole in human milk following intravaginal administration. Metronidazole is present in human milk following oral metronidazole administration, at concentrations similar to those found in plasma (see Data). The metronidazole vaginal gel achieves 2% of the mean maximum serum concentration of a 500 mg oral metronidazole dose [see CLINICAL PHARMACOLOGY]. The published literature reports no adverse effects in infants exposed through breastmilk to maternal orally administered metronidazole. There are no data on the effects on milk production.
Animal studies have shown the potential for tumorigenicity after oral metronidazole was administered chronically to rats and mice [see Nonclinical Toxicology]. The clinical relevance of these findings is unclear. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for NUVESSA, and any potential adverse effects on the breastfed child from NUVESSA or from the underlying maternal condition. Alternatively, a lactating patient may interrupt breastfeeding and choose to pump and discard breastmilk during treatment with NUVESSA and for 48 hours after the last dose and feed her infant previously stored human milk or formula.
Data
In a study of lactating women receiving oral metronidazole 600 mg (n=11) or 1200 mg (n=4) daily, mean maternal plasma concentrations were 5.0 and 12.5 mcg/mL respectively, within 2 hours following administration; the milk: maternal plasma ratio was approximately 1.
Pediatric Use
The safety and effectiveness of NUVESSA have been established in pediatric subjects between the ages of 12 and less than 18 years old. Use of NUVESSA in this age group is supported by evidence from a multicenter, open-label safety and tolerability study in 60 pediatric patients with bacterial vaginosis [see ADVERSE REACTIONS]and, evidence from adequate and well-controlled studies in adult women.
The safety and effectiveness of NUVESSA in pediatric subjects below the age of 12 years have not been established.
Geriatric Use
Clinical studies with NUVESSA did not include sufficient numbers of subjects 65 years of age or older to determine whether they respond differently than younger subjects.