UCSD: Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterial scourge. As its name suggests, MRSA is resistant to most common antibiotics and thus difficult to treat, particularly in children where it commonly causes complicated skin and skin structure infections. In a randomized, controlled clinical trial — the first of its kind — a multi-institution research team reports that daptomycin, part of a new class of antibiotics currently approved only for use in adults, is effective and well-tolerated in children. The findings are published in the March 2017 issue of Pediatrics.
“The safety and efficacy of intravenous daptomycin was comparable to
standard-of-care IV antibiotics used for hospitalized children, usually
vancomycin or clindamycin for MRSA and cefazolin for
methicillin-susceptible strains of S. aureus,” said first
author John Bradley, MD, professor of clinical pediatrics, co-chief of
the Division of Infectious Diseases at UC San Diego School of Medicine
and director of the Division of Infectious Diseases at Rady Children’s
“Daptomycin should provide a safe and effective alternative to
vancomycin, clindamycin or linezolid for IV treatment of invasive MRSA
skin infections. Concerns for vancomycin renal toxicity and clindamycin
antibiotic resistance were not present. There was no evidence of
daptomycin toxicity in the trial.”
The Food and Drug Administration is currently reviewing whether to approve daptomycin use in children.
MRSA infections are commonly associated with patients in hospitals
and nursing homes whose immune systems are weakened, but
community-associated MRSA (CA-MRSA) is widespread, readily transmitted
at daycare centers, playgrounds and in schools where children have
frequent skin-to-skin contact, share toys that have not been cleaned and
are more likely to have scrapes, abrasions and bites that offer
potential infection entry points.
CA-MRSA usually causes skin infections but can lead to more serious
consequences, such as pneumonia and infections of bones and joints.
Daptomycin is active against MRSA and was approved for use in adults in
2003 for treatment of skin and skin structure infections, and for
bloodstream infections three years later.
The new study was a prospective, randomized, investigator-blinded
study that included more than 250 daptomycin-exposed children, ages 1 to
17, to document safety and efficacy of the antibiotic in treating
pediatric skin and skin structure infections. Dosing was based on adult
experience, but researchers found that the younger the child, the more
quickly their bodies eliminated daptomycin. Thus pediatric doses
increased as the age of the research participants decreased.
“Most news these days is about the declining utility of antibiotics
as microbial resistance becomes more widespread and intractable,” said
Bradley. “These findings are encouraging. Daptomycin appears to be a
suitable, once-a-day alternative to existing antibiotics with harsher
Co-authors include: Chad Glasser, Hernando Patino, Minjung Yoon,
Diane Anastasiou, Dominik Wolf, and Paula Bokesch, Merck; Sandra L.R.
Arnold, University of Tennessee; Antonio Arrieta, Children’s Hospital of
Orange County; Blaise Congeni, Akron Children’s Hospital, Ohio; Robert
Daum, University of Chicago MRSA Research Center; and Tsoline
Kojaoghlanian, Children’s Hospital at Montefiore, Bronx, NY.
Funding for this research came, in part, from Merck & Co.