Gene predicts resistance to Pfizer's Xalkori
Drug resistance can be a problem with lung cancer chemotherapy with Pfizer's ($PFE) Xalkori (crizotinib), and a genetic biomarker published in Cell could help to find the patients most likely to stop responding to the drug, helping doctors to personalize treatment.
Xalkori is used to treat non-small cell lung cancer (NSCLC) patients with a specific mutation, where two genes have fused, but these patients' cancers often become resistant to the drug. The researchers, from Europe and Japan, found a mutated gene (MED12) that marked resistance to Xalkori in NSCLC, and also in other cancers and other chemotherapies as well.
The marker could be used to pinpoint patients at risk of developing resistance to particular drugs, so that they avoid any unnecessary or ineffective treatments.
By understanding the mechanisms of resistance, researchers can try to develop drugs that could prevent resistance from developing or circumvent resistance that has already occurred. Drugs that inhibit the transforming growth factor beta receptor (TGF-betaR) seem to restore responsiveness in cells with this mutation, but these are still just in clinical trials.