Onabet

Onabet® (sertaconazole nitrate) cream, 2%, is indicated for the topical treatment of interdigital tinea pedis in immunocompetent patients 12 years of age and older, caused by: Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum.

In the treatment of interdigital tinea pedis, Onabet cream, 2%, should be applied twice daily for 4 weeks. Sufficient amount of Onabet cream, 2%, should be applied to cover both the affected areas between the toes and the immediately surrounding healthy skin of patients with interdigital tinea pedis.

Not for ophthalmic, oral, or intravaginal use.

None.

WARNINGS

Included as part of the PRECAUTIONS section.

PRECAUTIONS

Local Adverse Reactions

If irritation develops, treatment should be discontinued and appropriate therapy instituted.

Physicians should exercise caution when prescribing Onabet cream, 2%, to patients known to be sensitive to azole antifungals, since cross-reactivity may occur.

Patient Counseling Information

See FDA-approved Patient Labeling (PATIENT INFORMATION)

The patient should be instructed to:

• Use Onabet cream, 2%, as directed by the physician. The hands should be washed after applying the medication to the affected area(s). Avoid contact with the eyes, mouth, vagina and other mucous membranes. Onabet cream, 2%, is for external use only.
• Dry the affected area(s) thoroughly before application, if you wish to use Onabet cream, 2%, after bathing.
• Use the medication for the full treatment time recommended by the physician, even though symptoms may have improved.
• Inform the physician if the area of application shows signs of increased irritation, redness, itching, burning, blistering, swelling or oozing.
• Avoid the use of occlusive dressings unless otherwise directed by the physician.
• Do not use this medication for any disorder other than that for which it was prescribed.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

In a rat dermal carcinogenicity study, topical administration of sertaconazole nitrate cream for up to 102 weeks did not increase the number of neoplastic lesions compared to control animals, at sertaconazole nitrate doses of up to 800 mg/kg/day (approximately 200 times the maximum recommended human dose based on a body surface area comparison).

No clastogenic potential was observed in a mouse micronucleus test. Sertaconazole nitrate was considered nonclastogenic in the in vivo mouse sister chromatid exchange assay. There was no evidence that sertaconazole nitrate induced unscheduled DNA synthesis in primary rat hepatocyte cultures.

At oral doses up to 60 mg/kg/day (16 times the maximum recommended human dose based on a body surface area comparison), sertaconazole nitrate exhibited no toxicity or adverse effects on reproductive performance or fertility in male or female rats.

Use In Specific Populations

Pregnancy

Pregnancy Category C

There are no adequate and well-controlled studies conducted with Onabet cream in pregnant women. Onabet cream should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Reproduction studies have not been performed with Onabet cream. Sertaconazole nitrate did not produce any evidence of maternal toxicity, embryotoxicity or teratogenicity in rats and rabbits at an oral dose of 160 mg/kg/day (40 times (rats) and 80 times (rabbits) the maximum recommended human dose based on a body surface area comparison). A reduction in live birth indices and an increase in the number of still-born pups were seen at doses of 80 and 160 mg/kg/day sertaconazole nitrate in an oral peri-and post-natal development study in rats.

Nursing Mothers

It is not known if sertaconazole is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when prescribing Onabet cream, 2%, to a nursing woman.

Pediatric Use

The efficacy and safety of Onabet cream, 2%, have not been established in pediatric patients below the age of 12 years.

Geriatric Use

Clinical trials of Onabet cream, 2%, did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug, and may not reflect the rates observed in practice.

In clinical trials, cutaneous adverse events occurred in 7 of 297 (2%) subjects (2 of them severe) receiving Onabet® cream, 2%, and in 7 of 291 (2%) subjects (2 of them severe) receiving vehicle. These reported cutaneous adverse events included contact dermatitis, dry skin, burning skin, application site skin tenderness.

In a dermal sensitization trial, 8 of 202 evaluable subjects tested with Onabet® cream, 2%, and 4 of 202 evaluable subjects tested with vehicle, exhibited a slight erythematous reaction in the challenge phase. There was no evidence of cumulative irritation or contact sensitization in a repeated insult patch test involving 202 healthy volunteers.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Onabet cream, 2%. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

In post-marketing surveillance for Onabet cream, 2%, the following were reported:

Cutaneous adverse events: erythema, pruritus, vesiculation, desquamation, and hyperpigmentation.

No information provided.

In a multiple dose pharmacokinetic trial that included 5 male subjects with interdigital tinea pedis (range of diseased area, 42 -140 cm²; mean, 93 cm²), Onabet cream, 2%, was topically applied every 12 hours for a total of 13 doses to the diseased skin (0.5 grams sertaconazole nitrate per 100 cm²). Sertaconazole concentrations in plasma measured by serial blood sampling for 72 hours after the thirteenth dose were below the limit of quantitation (2.5 ng/mL) of the analytical method used.