Topical Minocycline Foam for the Treatment of Impetigo in Children: Results of a Randomized, Double-Blind, Phase 2 Study
October 2016 | Volume 15 | Issue 10 | Original Article | 1238 | Copyright © October 2016
Shlomo Chamny MD,a Dan Miron MD,b Nadia Lumelsky MD,c Hana Shalev MD,d Elana Gazal PhD,e Rita Keynan,e Avner Shemer MD,f and Dov Tamarkin PhDe
aClalit Health Services, Tel-Sheva Clinic, Israel bClalit Health Services, Yasmin Clinic, Nazareth Illit; Rappaport School of Medicine, Technion, Haifa, Israel cClalit Health Services, Omer Clinic, Afula, Israel dClalit Health Services, Rahat Clinic, Israel eFoamix Ltd., Rehovo, Israel fDepartment of Dermatology, Chaim Sheba Medical Center, Sackler School of Medicine, Tel Hashomer, Israel
BACKGROUND: Currently available treatment options for impetigo are limited by either systemic side effects (for oral therapy) or lack of ease of use (for topical ointment). A novel foam formulation of minocycline for topical use may improve convenience and treatment utilization for pediatric patients with impetigo.
OBJECTIVE: To evaluate the safety and efficacy of topically applied minocycline foam (FMX-102 1% and 4%) in the treatment of impetigo and to determine the optimal therapeutic active ingredient concentration.
METHODS: In this randomized, parallel-group, double-blind, comparative clinical trial, 32 subjects aged ≥2 years with a clinical diagnosis of pure impetigo, impetigo contagiosa, or uncomplicated blistering impetigo were randomized to treatment with FMX-102 1% or 4%, twice daily for 7 days. Subjects were followed for up to 7 days post-treatment.
RESULTS: Clinical cure, defined as ≥80% cured lesions (fully recovered lesions, visually determined by investigators), was achieved by 57.1% and 50.0% of FMX-102 1% and 4% subjects, respectively, at the end of treatment (visit 3). Clinical success, defined as the absence of lesions, or the drying or improvement of treated lesions (decrease in size of affected area, lesion number, or both), was demonstrated in 81.3% and 78.6% of FMX-102 1% and 4% subjects, respectively, following 3 days of treatment (visit 2), in 92.3% and 100% of the respective subjects at the end of treatment, and in 100% in both groups at follow-up (visit 4). Bacteriologic success rates at the end of treatment, defined as complete pathogen eradication, were 85% and 74% in the FMX-102 1% and 4% groups, respectively. The bacteriologic success rate for MRSA infections was 100% (11/11), with no recurrences. Both FMX-102 1% and 4% were considered well tolerated and safe.
CONCLUSION: Topical minocycline foam may be a safe and effective new treatment option for impetigo in children, including those with MRSA. J Drugs Dermatol.
Impetigo is a highly contagious infection of the superficial layers of the epidermis.1 In the United States, it is the most common bacterial skin infection in children and the third most common skin disease overall.1 It is caused by Staphylococcus aureus and Streptococcus pyogenes, and, in recent years, by the potentially more serious methicillin-resistant S. aureus (MRSA) and gentamicin-resistant strains.2 S. aureus skin and soft-tissue infections (SSTIs) accounted for 14 million outpatient health care visits (ie, physician’s office, emergency room, and outpatient department) in 2005, making this a significant health problem in the United States.3 The prevalence of MRSA may be as high as 74% among SSTIs.4Oral minocycline and doxycycline are prescribed for the treatment of moderate-to-severe acne and rosacea.5,6 They are also used for treating impetigo and other skin infections, including those related to MRSA.7 Oral minocycline therapy is effective; however, its use is limited by systemic adverse effects, including upset stomach, nausea, diarrhea, dizziness, vertigo, and headache.8,9 The only topical antibiotics currently approved for impetigo are retapamulin and mupirocin; the use of the latter has been limited by emerging resistance.10Topical therapy is an important option for treatment of dermatologic conditions, and for control or cure of the underlying disease.11 The correct choice of delivery vehicle can influence drug performance and affect a patient’s adherence to therapy through improved ease of use.11 For patients with impetigo, the ointment formulations of mupirocin and retapamulin may present some drawbacks, such as unpleasantness in their application and the difficulty of removing them from skin and clothing, due to the high viscosity and nonvolatility of the ointment vehicle.12 The complexity of the regimen, such as mupirocin’s 3-times-daily regimen, may further undermine treatment adherence.