Targeting FGFR Mutations in Metastatic Urothelial Cancer - Episode 10
Strategies that can be used to counsel patients on molecular testing for FGFR mutations and what to expect from treatment with erdafitinib.
Arlene O. Siefker-Radtke, MD: With the erdafitinib [Balversa] approval in locally advanced or metastatic bladder cancer, have you used erdafitinib much in your own practice?
Scott T. Tagawa, MD, MS, FACP: Yes. I guess the definition of much is all relative. As a referral center, we see more patients with urothelial carcinoma than, I think, an average community practice. And therefore—and we test virtually everyone. There’s no confirmations if you don’t test. Maybe they’re there and we just didn’t know about it. Those are the key factors. And I would say for anyone that says, I’ve never seen it before, my question would be, what’s the volume? See one a year, maybe you’re not going to see it. But also, how often do you test? Because it should be approximately 1 in 5 that would have that. Anyway, the answer is yes. And I had my initial experience across a couple of different clinical trials, and I’ve also used it outside of clinical trials for patients that qualify for other trials or didn’t want to participate in a clinical trial. What is nice for me is that some didn’t qualify for clinical trials. But what was nice for me is that my clinical trial experience, more or less, mimics my nonclinical trial experience. Some of these patients that I have just prescribed erdafitinib to outside of a clinical trial we lose because they might do secret clinical trials, other aspects. And I found that most patients will have disease control. You mentioned the official RECIST [Response Evaluation Criteria in Solid Tumors] objective response rate, but if you look at a waterfall plot—I don’t need to tell you—but if one were to look at the waterfall plot, the majority of patients will have disease control. And not just official stable disease which can go up, it’ll get a little bit bigger. Most of the time is at least a little bit smaller or a lot smaller. And patients love to see that in terms of stands. Like other kinase inhibitors, a key factor for the clinical staff, physician, as well physician extenders, and patients and patients’ families, is to have good discussions upfront about the toxicity profiles. And the assessment early and often, to make sure that a higher-grade adverse event doesn’t happen. It happens some of the time, but a lot less when we catch something at a grade 1 level rather than down the line. I will always counsel ahead of time. It’s easy for me in an academic center. It’s not even just a cancer center, it’s an all-specialty center. We have a lot of ophthalmologists here, so it’s easy to get ophthalmology testing. I will teach them Amsler grid ahead of time, and we’ll go over that early, early on. And then we’ll counsel them. I will not let more than 2 weeks go by without at least having them see my NP [nurse practitioner] and we might do phone contact. And the other aspect that I think we mentioned before of the team, are the pharmacists. The pharmacist will sometimes reach out by phone as well. And with that overall strategy, my personal experience is that mimics the clinical trial. Most patients have disease control. Most patients can tolerate the drug, although sometimes they need adjustments in their dose.
Arlene O. Siefker-Radtke, MD: And you mentioned Scott, the impact of ophthalmology testing. How often do you send them to the ophthalmologist?
Scott T. Tagawa, MD, MS, FACP: I will mention the label and…but I’ll tell you, I don’t know that I’ve had any. Maybe one that started off with bad cataracts and different reasons for eye issues. I cannot remember one of them I had that went exactly on a monthly, at the beginning. As much as I can at baseline, I generally will tell them once they’ve already scheduled to already have an appointment for a month or so. A lot of times it’s not at the month, but to have that fee scheduled. And then I’ll remind them when I see them. Whether they go or not, I’m less concerned. Whenever they come to the clinic, we’ll do an Amsler grid and I’ll ask them if they’re doing it at home. Some will and some won’t. But we will also just ask, have they had any changes? And in my personal experience, and it’s true of many of the toxicities, but if there is a clinical issue in terms of, let’s say, vision change, and people are scared about going blind. If there is a visual change, it’s pretty rapid. I wouldn’t say 100% reversal, but it improves with adjustments in the dose. If it’s severe enough, we’ll hold the dose. And most of my patients, when I talk to them again, it’s already better, even if they haven’t seen the ophthalmologist in between yet.
Transcript edited for clarity.