Computer modelling technique predicts drug side-effects

In collaboration with the Press Association

A new computer modelling technique could be used to potentially identify the side-effects of new drugs.

The procedure, which is detailed in PLoS Computational Biology, screens specific drug molecules using the Protein Data Bank - a worldwide database that contains tens of thousands of three-dimensional protein structures.

Researchers at the University of California, San Diego (UCSD) have now used the technique to study a class of drugs called selective oestrogen receptor modulators (SERMs), which includes the common breast cancer drug tamoxifen.

Philip Bourne, professor of pharmacology at the university's Skaggs School of Pharmacy and Pharmaceutical Sciences, explained: "The computer procedure we developed starts with an existing three-dimensional model of a pharmaceutical, showing the structure of a drug molecule bound to its target protein; in this case, the SERM bound to the oestrogen receptor."

Scientists can then use computer analysis to search for other binding sites that match the drug's intended binding site and that could lead to unwanted side-effects.

Professor Bourne continued: "If a drug has adverse side-effects, it is likely that drug is also binding to an unintended, secondary molecule. In other words, the key that allows it to attach to its target fits more than one lock."

Once a second binding site has been identified, researchers will then be able to modify the drug so that it can no longer bind to the unintended site, thereby reducing the potential side-effects of experimental drugs before they are tested in humans.