BACKGROUND: Cutaneous bacterial infections are common in children and adults and 
frequently are caused by Staphylococcus aureus (S. aureus). Treatment failures 
with topical agents are not uncommon and have been shown to be secondary to 
bacterial resistance.
OBJECTIVE: To determine clinical and bacteriological efficacy of retapamulin 
ointment 1% in treatment of patients with cutaneous bacterial infections caused 
by methicillin-resistant S. aureus (MRSA) and other bacteria.
METHODS: Prospective, nonrandomized, uncontrolled, open label, single center 
trial conducted between April 2008 and November 2012 that evaluated efficacy of 
retapamulin ointment 1% in the treatment of impetigo, folliculitis, and other 
minor soft tissue infections in children and adults. Fifty patients, who 
presented to a dermatology outpatient clinic and were clinically diagnosed with 
impetigo, folliculitis, or minor soft tissue infection suitable for treatment 
with a topical antibiotic, were screened. Thirty-eight patients were enrolled 
and received treatment: topical retapamulin ointment 1% twice daily for 5 days. 
Seven patients were MRSA positive and qualified for the primary efficacy 
population. One patient withdrew due to an adverse event. Clinical and 
microbiological exams were performed at baseline and follow-up 5 to 7 days later 
to assess clinical, microbiological, and therapeutic responses. Primary outcome 
was clinical response at follow-up in primary efficacy population with MRSA 
isolated as the baseline pathogen. Secondary outcomes included clinical, 
microbiologic, and therapeutic responses in patients who were culture positive 
for any species of bacteria.
RESULTS: Clinical response at follow-up in the primary efficacy population 
(MRSA-positive patients) was not sufficiently powered to demonstrate 
significance; however, outcomes were excellent, with 7 of 7 patients 
demonstrating clinical success (5 of 7) or clinical improvement (2 of 7) at 
follow-up. Barring lack of significance due to small total sample size for 
patients who were culture positive for any species of bacteria (n = 35), overall 
success rates were favorable for clinical, microbiologic, and therapeutic 
responses with values of 66%, 97%, and 69%, respectively. Adverse events (AEs) 
were mild or moderate in severity. No serious AEs were reported.
CONCLUSION: Safety profile appears favorable given the low number of AEs. Study 
design limits conclusions that can be drawn. Nevertheless, this study supports 
use of topical retapamulin 1% ointment in treatment of cutaneous bacterial 
infections, particularly those caused by S. aureus, including MRSA.