Will my compounds interact with other medicines?

Predicting Drug/Drug interactions

One of the most common reasons for drug-drug interactions is inhibition of specific P450 isozymes.  A drug may be metabolised specifically by a particular P450, but may have the capacity to inhibit a whole range of different isozymes, thus affecting the pharmacokinetics of other therapeutic agents taken concomitantly.

The CXR approach

Drug/drug interactions may be classified as mechanism-based or idiosyncratic. While the idosyncratic class of interactions may be difficult, if not impossible, to predict, our understanding of drug transport, metabolism and excretion means that we can predict mechanism-based interactions with some confidence. CXR can also advise on the design of clinical studies to minimise the risk of drug/drug interactions, thus enabling the intelligent use of therapeutic drug monitoring to ensure the safety of patients and volunteers, and maximising the chances of success in Phase 1 trials.

To date, the majority of mechanism-based drug-drug interactions have proved to be mediated by inhibition of key drug metabolising enzymes (usually of the cytochrome P450 family). CXR Biosciences has a well established approach to the prediction of this class of drug-drug interactions, using human liver microsomes and recombinant enzymes to determine which isozymes are able to metabolise the candidate and whether any of them are subject to inhibition. By combining this experimental approach with an extensive knowledge of drug metabolism we are able to predict metabolic drug-drug interactions with a good degree of confidence.