Duke University Medical Centre has been researching a drug that can help to cure heart and bloodstream infections of staphylococcus aureus infections, the bacteria responsible for MRSA (methicillin-resistant Staphylococcus aureus)
Because of this trial, the FDA has approved Daptomycin for treating infections caused by S. aureus. It is the first new drug in twenty years to be approved. This can mean a lot of hope for doctors that are finding new strains of MRSA harder and harder to treat.
Daptomycin was approved in 2003 to treat S. aureus skin infections, but had not been approved for other types of infections. In August of 2006, the New England Journal of Medicine published the study. Extract.
2 Million Staph Infections per Year
S. aureus bacteria are quite common, and do not cause a problem for the general public. However, in people with weakened immune systems or those that have had certain medical treatments, it can get into the blood stream and cause serious infections. There are approximately 2 million infections and 90,000 deaths each year because of S. aureus.
“The rising prevalence of S. aureus infections and the organism’s increasing resistance to drugs make these bacteria a growing threat to medical care throughout the world,” said Ralph Corey, M.D., a professor of infectious diseases who participated in the study.
Treating S. aureus can be difficult since there are strains that have become resistant to commonly used antibiotics. Known as MRSA, these strains are generally only treatable with Vancomycin, and some strains have shown resistance even to that.
With the number of infections rising each year, along with the bacterias resistance to medications, makes staph and MRSA a serious health concern.
The study tested Daptomycins ability to fight both S. aureus and the MRSA strains on bacteraemia and endocarditis. Endocartitis is particularly severe, and can involve several areas of the heart, most often with patients that already have heart disease.
The test followed 246 patients with bacteraemia in 44 centers in four countries. The patients were split into two groups, one receiving six milligrams of Daptomycin per kilogram of body weight, and the other receiving a four-day course of Gentamicin and a full course of either penicillin or Vancomycin.
The researches monitored the patients until discharge, and then again six weeks after treatment ended. Daptomycin proved as effective as other the standard therapy, and more so against the MRSA strands. Standard therapy, however, worked better on the non-resistant strains of S. aureus. Both took about eight or nine days to clear up an infection.
The thought is that by having a new drug available that is fight MRSA and staph infections gives doctors more options, and may also help to slow the spread of drug resistant strains.
The test also studied the safety of Daptomycin, since dosages were higher than treatments that were previously used for skin infections. Earlier studies had suggested that higher doses might have significant side effects. However, Daptomycin was easier on the kidneys than the standard therapy. Gentamicin is known to have potent renal toxicity. The patients taking Daptomycin had fewer adverse kidney problems and had better kidney performance.
Image: Digitized electron micrograph of clusters of methicillin-resistant Staphylococcus aureus (MRSA) bacteria.. Wellcome Images Creative Commons.