New Drugs Discovered that Disarm MRSA

Advertisement

Like disarming a bomb, a researcher has discovered new anti-pathogenic drugs that turn off the killing power of MRSA—methicillin resistant Staphylococcus aureus—rather than kill the bacteria themselves. This finding comes at a time when the only two antibiotics that still are effective against MRSA are beginning to encounter strains resistant to them.

The Challenge of Fighting MRSA

MRSA is a type of staph bacteria that currently is responsible for about 20,000 deaths per year in the United States. Because vancomycin and linezolid are the only two antibiotics that still have any effect against MRSA, and with their ability to continue being effective in question, healthcare professionals and others are concerned they will run out of treatment options.

MRSA infections mostly occur as skin infections, with the most severe cases found in healthcare settings and among older adults. However, a recent study found a growing number of infections in children. A nationwide report found the percentage of head and neck infections caused by MRSA more than doubled in children from 2001 through 2006, going from almost 12 percent to 28 percent.

Advertisement

New Anti-Pathogenic Drugs Against MRSA
At Case Western Reserve University School of Medicine, Menachem Shoham, PhD, associate professor and researcher in the department of biochemistry, has discovered new drugs that prevent MRSA bacteria from producing the poisons that cause disease. These new drugs block a bacterial protein called AgrA, which is the main molecule that causes the release of toxins from MRSA bacteria.

Shoham notes that “contrary to antibiotics, these new anti-pathogenic drugs do not kill the bacteria. And since the survival of the bacteria is not threatened by this approach, the development of resistance, like that to antibiotics, is not anticipated to be a serious problem.”

Shoham utilized computer power to help sort through 90,000 compounds to uncover which ones would fit into the activation site on AgrA. After finding about 100 with potential, further testing left him with more than a dozen compounds. He noted that “such anti-pathogenic drugs may be used for prophylaxis or therapy by themselves or in combination with an antibiotic.”

The discovery of new drugs that have the potential to disarm MRSA bacteria without killing them is an important one. When we can expect such drugs to become available is not known.

SOURCES:
Case Western University
Gorwitz RJ et al. Journal of Infectious Diseases 2008; 197:1226-34
Naseri I et al. Archives of Otolaryngol Head Neck Surg 2009 Jan; 135(1): 14-16

Advertisement