“New-Look” Opioids: Biased Ligands

Between the illicit use of opioids and attendant overdoses, and accidental overdoses with prescribed drugs, overuse of opioids has become a serious problem. At the same time, finding that fine balance between minimizing the risk of opioid misuse and abuse while at the same time providing access to treatment for patients who need pain control presents an ongoing challenge. Efforts to discover and develop better agents have led to what we term “new-look” opioids. We summarize here one such approach—known as biased ligands. By targeting a subset of GPCR signal transduction, this approach attempts to increase the separation between therapeutic and adverse effects.