The devil is in the assay

The failure of a Phase III trial of Bristol-Myers Squibb Co.'s Opdivo nivolumab in first-line NSCLC doesn't shed much light on what PD-L1 expression level predicts patient benefit, because the uniqueness of the different assays used by the leading immuno-oncology companies makes comparison near impossible.

While Opdivo's failure may give Merck & Co. Inc.'s Keytruda pembrolizumab a lift, it may not matter if forthcoming combination therapies provide a similar or greater benefit than Keytruda in the front-line setting independent of PD-L1 status. ...