Dermatologicals

Retapamulin

1 g contains 10 mg retapamulin (1% w/w).

Ointment Smooth, off-white ointment.

Short term treatment of the following superficial skin infections:

Impetigo.

Infected small lacerations, abrasions, or sutured wounds.

Consideration should be given to official guidance on the appropriate use of antibacterial agents.

Retapamulin is for cutaneous use only.

Adults (aged 18-65 years), adolescents (aged 12-17 years), infants and children (aged from nine months to 11 years)

A thin layer of ointment should be applied to the affected area twice daily for five days.

The area treated may be covered with sterile bandage or gauze dressing.

Safety and efficacy have not been established in the following:

• Impetiginous lesions >10 in number and exceeding 100 cm2 in total surface area.

• Infected lesions that exceed 10 cm in length or a total surface area >100 cm2.

In patients aged less than 18 years the total surface area treated should be no more than 2% of the body surface area.

Patients not showing a clinical response within two to three days should be re-evaluated and alternative therapy should be considered.

Renal impairment

No dosage adjustment is necessary.

Hepatic impairment

No dosage adjustment is necessary.

Infants under nine months of age

The safety and efficacy of retapamulin ointment has not been established in paediatric patients less than nine months of age.

Elderly (aged 65 and older)

No dosage adjustment is necessary.

Known or suspected hypersensitivity to retapamulin or to the excipient.

In the event of a sensitisation or severe local irritation from the use of retapamulin ointment, treatment should be discontinued, the ointment carefully wiped off, and appropriate alternative therapy for the infection instituted.

Retapamulin ointment must be kept away from the eyes and mucous membranes. Epistaxis has been reported with use of Altargo on nasal mucosa.

Care must be taken to avoid ingestion.

Retapamulin should not be used to treat infections known or thought likely to be due to MRSA.

In clinical studies of secondarily infected open wounds, the efficacy of retapamulin was inadequate in patients with infections caused by methicillin-resistant Staphylococcus aureus (MRSA). The reason for the reduced clinical efficacy observed in these patients is unknown.

Alternative therapy should be considered if there is no improvement or a worsening in the infected area after 2-3 days of treatment.

Retapamulin should not be used to treat abscesses.

Retapamulin ointment contains butylated hydroxytoluene, which may cause local skin reaction (e.g. contact dermatitis), or irritation to the eyes and mucous membranes.

As with other antibacterial agents, prolonged use of retapamulin may result in overgrowth of non-susceptible micro-organisms, including fungi.

The effect of concurrent application of retapamulin and other topical products to the same area of skin has not been studied, and is not recommended.

In human liver microsomes, retapamulin was shown to be a strong inhibitor of CYP3A4. However, since plasma concentrations of retapamulin during topical application have been low, it is not expected that concurrent systemic administration of CYP3A4 substrates will result in clinically important inhibition of their metabolism by retapamulin.

Co-administration of oral ketoconazole 200mg twice daily increased mean retapamulin AUC(0-24) and Cmax by 81% after topical application of retapamulin 1% ointment on the abraded skin of healthy adult males. Nevertheless, the highest plasma concentrations recorded were low (< 10.5 ng/ml in the absence of ketoconazole and < 17 ng/ml in the presence of ketoconazole.

Systemic exposure to retapamulin has been low following topical application of 1% ointment in adult and paediatric patients aged 2 years and older (maximum plasma concentration < 20 ng/mL). Therefore it is not expected that clinically important increases in plasma concentrations of retapamulin will occur in patients aged 2 years and older who are also receiving CYP3A4 inhibitors.

In children aged from 9 months to 2 years it is possible that higher plasma concentrations may occasionally occur during treatment with retapamulin 1% ointment compared to older children and adults. Therefore caution is advised if retapamulin 1% ointment is administered to children in this age group who are also receiving CYP3A4 inhibitors, as further increase in systemic exposure to retapamulin may occur upon CYP3A4 inhibition.

In clinical studies in which 2150 patients with superficial skin infections applied Altargo, the most commonly reported adverse reaction was application site irritation, which affected approximately 1% of patients.

The following convention has been used for the classification of frequency:

Common

>1/100 to <1/10

Uncommon

>1/1000 to <1/100

Not known

(cannot be estimated from the available data)

Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.

GlaxoSmithKline

(POM)

12 March 2012