Tool to predict bacteria's future response to new drug

With a growing number of bacteria developing drug-resistance, researchers have now developed a tool to predict if a new drug would be effective against future counter-moves of the bug that it targets.

The new software called OSPREY can predict long-term effectiveness of new drugs ahead of time, before the drug is even tested on patients, the researchers noted.

"This gives us a window into the future to see what bacteria will do to evade drugs that we design before a drug is deployed," said co-author Bruce Donald, a professor of computer science and biochemistry at Duke University in Durham, US.

The researchers used the program to identify the genetic changes that will allow methicillin-resistant Staphylococcus aureus, or MRSA, to develop resistance to a class of new experimental drugs that show promise against the deadly bug.

From a ranked list of possible mutations, the researchers zeroed in on four tiny differences.

When the researchers treated live bacteria with the new drug and sequenced the bacteria that survived, two of the genetic changes that the algorithm predicted actually arose.

"If we can somehow predict how bacteria might respond to a particular drug ahead of time, we can change the drug, or plan for the next one, or rule out therapies that are unlikely to remain effective for long," study co-author Pablo Gainza-Cirauqui, who is also from Duke University, explained.

As bacteria reproduce rapidly, drug-resistant bacteria are constantly evolving, and researchers have to constantly develop new ways to kill them.

The software they developed is a open-source and freely available for any researcher to use.

The findings appeared in the journal Proceedings of the National Academy of Sciences.