May 20, 2008 (CIDRAP News) – The US Food and Drug Administration (FDA) recently offered another antibiotic option for combating inhalational anthrax in children by approving the quinolone drug levofloxacin (Levaquin).
In a letter dated May 5, the FDA endorsed the use of levofloxacin, made by Ortho-McNeil, in children 6 months of age and older. The agency had approved use of the drug for postexposure treatment of anthrax in adults in 2004.
Levofloxacin is also used in adults to treat pneumonia, bacterial sinusitis and bronchitis, and complicated skin and urinary tract infections, according to the FDA. It is not approved for children for anything but anthrax.
The first-line treatments for anthrax in both children and adults are ciprofloxacin and doxycycline, according to a report by Centers for Disease Control and Prevention (CDC) experts in the April issue of Emerging Infectious Diseases. The report was based on a 2006 conference on public health and clinical guidelines for anthrax.
The article says that because safety data on use longer than 28 days are lacking, levofloxacin is recommended as a second-line postexposure drug for adults, "to be reserved for instances where medical issues may call for its use." The report lists amoxicillin as a second-line treatment for children, provided the anthrax strain involved is susceptible to penicillin.
Clinical trials have shown an increased incidence of musculoskeletal adverse events, such as joint pain, arthritis, and tendonopathy, in children treated with levofloxacin, according to the FDA approval letter. One study, which compared the medication with a non-quinolone antibiotic, showed musculoskeletal problems were significantly more common in the levofloxacin group, but none were serious, and they resolved in about a week.
The FDA letter says the recommended levofloxacin dosages for children are based on body weight: 500 milligrams (mg) once daily for those weighing more than 50 kilograms (kg) (110 pounds), 8 mg per kg every 12 hours for those weighing less.
Stern EJ, Uhde KB, Shadomy SV, et al. Conference report on public health and clinical guidelines for anthrax. Emerg Infect Dis 2008 Apr;14(4) [Full text]
CIDRAP anthrax overview