Maintenance Therapy in Squamous NSCLC

Transcript:Benjamin Levy, MD: Let’s move to maintenance in squamous cell. We know a lot about maintenance in the non-squamous population. Pemetrexed has shown a survival advantage in both a switch maintenance and a continuation maintenance strategy. So there are clear indications for maintenance approaches for pemetrexed in the non-squamous. Squamous cell, a little more murky data on whether there’s a real role for maintenance approaches. I think there have been some data for gemcitabine with the IFTC study, a study looking at maintenance gemcitabine or switch maintenance of erlotinib versus best supportive care showing a PFS advantage that I think carried over into the squamous cell, the subset of patients with squamous cell.

We have some other studies, the SATURN study. We can certainly have different opinions about that. The PFS benefit did seem to carry over into the squamous cell population. We’ve had some others, the Fidias trial, early versus delayed docetaxel, subset analysis not done on the squamous cell population but there was at least a trend towards overall survival in that study, not statistically different. I’ll throw this to both of you. You’ve got a patient, four cycles of chemotherapy, your chemotherapy of choice. Patient had tolerated treatment well, has achieved stable disease after four to six cycles, maintenance or no maintenance, Paul?

Paul K. Paik, MD: I discussed the data that we don’t really have ground to stand on, formally speaking, in terms of improvements in overall survival for the things that for me at least make sense. But I tell them also that there is this PFS benefit that’s there for gemcitabine in terms of the carboplatin/gemcitabine regimen and that the conceptual framework is in place for lung adenocarcinoma. We get to a point where the population data for any trial breaks down on an individual level. And so if you have someone who’s had a good response even up to the fourth cycle or the sixth cycle of a platinum doublet who has squamous lung cancer, it stands to reason that continuing some form of maintenance, there you can provide a rationale for doing that. And so I talk about it.

I often times do recommend giving maintenance gemcitabine for patients who start carboplatin/gemcitabine as a result in that setting. But, again, we need to wait for the data to come out. We will know what the data is for maintenance Abraxane in conjunction with carboplatin/Abraxane in terms of the ABOUND study. So that will be very interesting to follow. It’s important to note a study that I’m sure we’ll talk about in a little bit, looking at necitumumab paired with cisplatin/gemcitabine. Necitumumab was given as a maintenance treatment also in this population. So it’s something with which we have experience, something that we will need to wait for in terms of formal data to really solidify, I think, as a standard.

Benjamin Levy, MD: I agree with you. For some of my patients prior to the Abraxane story being woven in squamous cell, I was considering maintenance gemcitabine for those patients who had tolerated four cycles and then are at least achieving stable disease or having a response, something to consider. There is not a lot of data to support that decision, and I think this is where, again, medicine becomes an art, not a science. But we were doing that.

And, as you mentioned, the ABOUND study that we are participating in looking at four cycles of carboplatin/nab-paclitaxel weekly in those patients who at least achieve stable disease and are tolerating treatment are randomized in the maintenance setting to day 1, day 8 out of a 21 day cycle of Abraxane. So hopefully we’ll have answers from this. We’ve been very competitive in enrollment, and I will tell you that our experience with this drug so far in terms of response has mirrored what we’ve seen in the Socinski data. Ed, your thoughts on maintenance and whether you use it or not.

Edward S. Kim, MD, FACP: Yes, I like that ABOUND study. I think if most of us bet, it will come out positive because we used to make fun of our surgical colleagues when we say, “to cut is to cure,” and we say, ah, they’re going to cut. But it’s the same thing with medical oncologists. We have this desire to want to continue to treat our patients because we do believe there’s benefit. The harmful effects is what gets in the way. In non-squamous where pemetrexed has been so easy, there’s a single dose, a single schedule, the side effects are low, again, very transformational drug in how we approach folks. It’s a no-brainer. You’re just going to decide if you’re using bevacizumab first-line, whether you’re going to continue it or stop or save it. And in squamous patients, it’s been very, very, individualized.

There are many patients after four cycles of chemotherapy who have squamous cell that look beat up even though they’re benefitting, and you feel bad about giving them maintenance. There’s other patients who you feel like you want to give more doublet but you know going to 6, or 8, or 10 just like in the old days when oncologists again had this propensity to do that because of that same feeling, okay, maybe I’ll dial it back and give them maintenance. So it’s very individualized and that’s tough for a community oncologist to make that decision because it’s not as logical as it is non-squamous. And nobody likes to use erlotinib there because they just don‘t see the benefit. Adoption usually follows efficacy, right? If you see something that’s working and you have a patient or two that’s benefitted, you’re going to adopt. I think that’s the struggle right now.

Benjamin Levy, MD: We’ll talk a lot about immunotherapy in a bit, but does the implementation of immunotherapy in squamous, sway people to use or not use maintenance, given that you’ve got a really good drug and perhaps the rationale is if you give maintenance, you beat the patient up and they’re not able to get to nivolumab. The alternative is you may get them because you’ve got them on a schedule, and when they do progress, there are immunotherapeutic options available.

Edward S. Kim, MD, FACP: I think all of us are kind of looking into the crystal ball and seeing that it will be more of a triplet/maintenance PD-1 approach, hopefully, in the next year or so. Right now, I think the PD-1 aspect has changed everything on squamous. We’re actually almost happy when people can get to those drugs now because we want that opportunity to give that patient an immunotherapy. Immunotherapy hasn’t cured the world or anything, but it’s the most promising therapy in squamous that has come out in the last two decades. People are waiting to use it.

Paul K. Paik, MD: That’s right. I think it’s difficult to comment on that because of what Ed had mentioned which is the landscape is going to shift with first-line combination studies. I think we need to defer discussion on that until we see what the results are for that upfront setting. That’s right.

Transcript Edited for Clarity