BARDA raises concerns over colistin-resistant bacteria found in U.S. patients

The Biomedical Advance Research and Development Authority (BARDA) recently said that it is anticipating a threat posed by the bacterial gene mcr-1, which confers resistance to the antibiotic colistin and was found in a bacterium isolated from a patient in the United States.

While the bacteria is sensitive to other forms of antibiotics, authorities are concerned that mcr-1’s appearance in the United States may signal the arrival of a readily-transferrable colistin-resistance in the American healthcare system. Colistin resistance is concerning to officials because it is generally viewed as an antibiotic of last resort for patients. Amongst multidrug-resistant bacterial strains, one that is particularly concerning is the cabapenem-resistant Enterobacteriaceae (CRE). Colistin is one of the few antibiotics proven to be effective against CRE.

BARDA is currently working on medical countermeasures in response to the potential threat, particularly with one candidate called plazomicin. Plazomicin is a novel member of the aminoglycoside class of antibiotics, a group that includes better-known antibiotics like gentamicin and amikacin.

As part of its response, BARDA has entered into a public-private partnership with GlaxoSmithKline to develop other medical countermeasures for these antibiotic-resistant bacteria. BARDA is currently undergoing two Phase III clinical trials with the antibiotic, one focusing on the treatment of patients with serious infections due to CRE and the other focusing on the treatment of patients with complicated urinary tract infections.

BARDA has given no timetable for clinical trial completion at this time.