During a Targeted Oncology case-based roundtable event, Christopher R. Flowers, MD, MS, discussed with participants their experiences referring patients for chimeric antigen receptor T-cell therapy and using bridging therapy. This is the first of 2 articles based on this event.
CHRISTOPHER R. FLOWERS, MD, MS: What proportion of your patients with DLBCL [who are considered eligible] actually go on to receive CAR T-cell therapy? I know I’m very much an outlier on this particular question in that the vast majority of my patients I see—because we’re at a CAR T-cell therapy center—are able to go on to CAR T-cell therapy.
SHAN GUO, MD: [For me, it is] 50% to 55% [of patients]. Many of my patients are older and frail so we don’t ever get to the point of CAR T-cell therapy consideration if they have relapsed. For most patients, if there is relapse, we’re looking at second line therapy, more in the palliative fashion. But some of the elderly patients respond well. I did have a few patients who surprised me with how well they did with a CAR T-cell therapy. So it’s not because we send everybody to CAR T-cell therapy, it’s just we only have that many patients who are eligible for CAR T-cell therapy. If they get referred to the CAR T cell center, at least 50% of patients will follow through.
INNA SHMERLIN, MD: My rate is definitely not 90%; it’s probably closer to 50%. Before I refer them, I speak with our transplant colleague, and get an idea of what they think. I’d say at least half of my patients have gotten it. But I usually run it by the transplant physician before I send them over.
FLOWERS: Have you found that’s been a helpful strategy…in terms of identifying those patients who it may not make sense to send?
SHMERLIN: It is. It saves the patient time and money. It saves the transplanters time because they’re busy. I think it’s very helpful. I have their numbers on my speed dial. Even before I send a patient for a stem cell transplant, I do the same thing. I ask them, “How do you want me to proceed? Do you think this is a candidate?”
SAMIR MAZHARUDDIN, MD: Most of my patients are a bit frail, so it doesn’t come into the picture. And so out of our selection of who we refer and early coordination with the CAR T-cell therapy physician, we can achieve a higher number of patients who actually get to CAR T-cell therapy.
KATHERINE WANG, MD: My experience is very similar. I have a good relationship—within our network we have a CAR T group. Late last year, I referred a patient. The patient got in right away. I’ve learned it takes months to get a patient on the CAR T program. So, usually, for someone with high-risk or double-hit [lymphoma], or double expressors, I try to refer them to the CAR T-cell therapy group early after the first frontline therapy, at least get them established with transplant care. Then they will give me the recommendation whether the patient continues to be observed or needs to prepare for the next step.
BRAMHAM REDDY, MD: I have referred a couple of patients. I live about 2 hours north of Houston, but I only have 1 patient who has successfully gone through the program. Part of the reason is that we don’t have a good intensive care unit set up, so that’s one of the limitations. But I did have one patient who underwent CAR T-cell therapy.
FLOWERS: How long does it take typically between the CAR T-cell collection and infusion in your practice region? Do you have a sense for that?
MAZHARUDDIN: I think it’s a few weeks, but mainly the CAR T-cell therapy–performing physician handles that.
FLOWERS: But it is not something you’ve perceived as being a problem in terms of the care of your patients.
MAZHARUDDIN: Right, I’ve have not heard of any issues.
FLOWERS: Does anyone else want to comment on the timing between collection and infusion?
GUO: Once it’s collected, normally it doesn’t take that long. That’s my impression. Most of the time it’s the insurance clearance. For example, if the patient gets seen in a few weeks, in the meantime we’ll start bridging therapy. I think we almost always have to start a bridging therapy because the whole thing is going to take at least, from the time you start authorization and T cell collection—if it works well the first time, sometimes they have to go for the second round of collection, so the whole thing can take several months—but once it’s collected, I’ve seen patients getting the infusion within 2 weeks.
FLOWERS: I would say our typical times are usually 2 weeks, sometimes even less than that for patients from the time of collection to infusion. I think the delays you’ve mentioned are the ones that we most commonly are concerns. It’s the insurance approvals, and that process very rarely delays from collection to infusion with the most common products that we use.
Being a transplanter all my career, I’ve thought about transplant eligibility criteria as the criteria for cellular therapy. But we definitely see a number of patients who would not be considered standard autologous stem cell transplant candidates who are very clearly CAR T-cell therapy candidates. In fact, very commonly on the inpatient service, I will have 3 or 4 patients on at a time who are over the age of 70. I think at one point, the last time I was on service I had about 6 patients over the age of 70 who were getting CAR T-cell therapy all at the same time and all have tolerated it quite well. I think the one thing in particular that we think about there are the 4-1BB-based CAR T-cell products, where the toxicity tends to be a little bit less.