PD-L1 Status: What Is the Current Role?

Transcript:Gerald J. Berry, MD: Particularly for advanced lung cancer patients, I think PD-L1 testing should be performed. One can argue whether or not it should be done up front in the lower-stage patients. We tend to do it for a variety of reasons, but I certainly think that every advanced lung cancer patient, at least in the non—small cell camp, should be tested. The advantage is that you at least provide an opportunity for an additional, or a separate, primary new therapy that you wouldn’t have had unless you tested the patient.

I think that you have to recognize that the immunotherapies, the PD-L1 therapies, do have side effects, and some of those side effects can be quite serious. So, I think the more information that we have up front, the better. One can certainly go ahead and offer the drugs to patients, but if it were me, I would want to know what my status is before I decide whether or not I am going to take the therapy. Again, there are advantages in that testing provides information. It also provides information on patients who may not be eligible for the drug.

Heather Wakelee, MD: We’re also testing all patients for PD-L1 with a 22C3 assay, and that’s the assay that’s tied in with pembrolizumab. The reason we do the testing is that we had randomized phase III data this year that showed, for patients who had a greater than 50% PD-L1 level by that particular test, the 22C3 assay, they actually did better if we started them on pembrolizumab versus chemotherapy. But that’s in the context of patients who did not have EGFR mutations and who did not have ALK mutations.

So, it’s really important to not just test their PD-L1, but to also test for molecular drivers, especially EGFR and ALK mutations. If EGFR and ALK mutations are found, we’ll go after that as our primary treatment plan and then bring in PD-L1 treatment later. The PD-L1 testing, though, should be up front for all patients. If they’ve already had chemotherapy, we do not always test them. We will, sometimes, get a gauge of how likely they are to benefit—especially if it’s someone who we think might be at higher risk. But, in general, it’s tested at the point of diagnosis.

Gerald J. Berry, MD: There’s growing and growing evidence that PD-L1 testing and PD-L1 results are very important in the management of non—small cell lung cancer patients. I think that’s one of the reasons to argue for up front testing for PD-L1 in all new lung adenocarcinomas and squamous cell carcinomas. There’s not only evidence that it’s effective as a second-line therapy, but there are also recent published data establishing it as a very good option as a first-line therapeutic intervention. I think that, more and more, we’re now looking at evidence, or trials, that are combining PD-L1 with conventional chemotherapy. So, there are all kinds of different avenues that are going to be available for patients, but that first requires that we know what their PD-L1 statuses are.

Transcript Edited for Clarity