Chung-Han Lee, MD, PhD: At this time, I would say that there is an unclear role for PD-L1 testing within patients who have gotten the combination of a TKI [tyrosine kinase inhibitor] and an immune checkpoint inhibitor. Certainly, we do have evidence that PD-L1 staining may be relevant for immunotherapy/immunotherapy combinations, and maybe even for atezolizumab/bevacizumab. However, based off what we’ve seen with axitinib/pembrolizumab and lenvatinib/pembrolizumab, it’s a little bit less clear whether or not PD-L1 staining is able to predict response.

Thomas E. Hutson, DO, PharmD: One of the interesting findings from the atezolizumab/bevacizumab trial was the PD-L1 status and whether that would predict or enrich a patient population that would do better. From that trial, it appears that, indeed, it does. We have looked at PD-L1 status in other trials, and PD-L1 status does enrich the patient population. If you have that, you do better. Or, you are more likely to do better when it comes to efficacy endpoints. The problem has been that if you were PD-L1—negative with many agents, it didn’t negate the benefit over sunitinib as the comparator. As we move forward, whether or not PD-L1 status will be enough of a differentiator to help one select agents is unclear in kidney cancer. Certainly, there is some experience in other cancers, such as lung cancer, in it being a differentiator. At the present, I would not recommend routine testing or stratification of agents based upon PD-L1 status outside of a trial setting.

Transcript Edited for Clarity