Tuesday, March 12, 2019

CAR-T Hospitalization

Interesting research about the hospitalization of patients who receive CAR-T treatments.

First, a reminder of what CAR-T is, because it has gotten quite a bit of attention in blood cancer circles in the last few years.

CAR-T stands Chimeric Antigen Receptor T-cell therapy. It involves T cells, one of the types of immune cells in the body. T cells are one of the ways the body fights invaders, like bacteria and viruses. But cancer cells are not invaders -- they are part of the body that won't die. So T cells need to be taught to fight them. With CAR-T, some T cells are removed from the patient's body and changed in a lab so they will recognize and fight cancer cells. Then they put back into the body to do their job. One of the great things about the treatment is that T cells have a memory -- if they find an invader that they have already encountered, they will know to fight it again. So if a CAR-T treatment is successful once, it should keep on recognizing and fighting those cancer cells whenever they come back.

As always, if you want to learn more about CAR-T and Follicular Lymphoma, I highly recommend the site CAR-T and Follicular Non-Hodgkin's Lymphoma.

CAR-T also has some potentially bad side effects. When the body fights off and kills huge numbers of cells all at once, it can have a reaction called Cytokine Release Syndrome. This can be severe enough that a few early CAR-T patients died from it. Doctors seem to be better at controlling it now. CAR-T can also cause some neurological problems.

Because of the seriousness of the potential side effects, CAR-T patients often need to stay in the hospital after treatment. That's what two recent studies focused on. Both were published in Biology of Blood and Marrow Transplantation.

One of the two studies deals with very young people (under 25) who have had CAR-T treatment. I'm going to skip that one; it's extremely rare that a young person gets Follicular Lymphoma.

The other study looks at patients who at 18 and over; I think that covers everyone who reads this blog.

The study is called "Emerging Trends in Chimeric Antigen Receptor T-Cell Immunotherapy in Adults from the Vizient Clinical Database."

The study looks at data that is being compiled by Vizient, which tracks information about patients in clinical trials. They tracked 735 patients who had CAR-T between October 2017 and August 2018. For the study, they were interested in what kind of follow-up was needed by the patients. 61.5% of patients has Diffuse Large B Cell Lymphoma. About 4% had Follicular Lymphoma, and the rest had other blood cancers.

They found that the median hospital stay was 15 days, and the media cost of the stay was $82,059. (That's for the hospital stay only -- the treatment itself can cost around $400,000.) During the hosital stay, almost 70% of the patients had a reaction to the treatment, and 12% had other complications. Other side effects: 56% had fever, 55% had a change in blood pressure, 25% had nausea, 18% had headache or migraine, 15% had kidney failure, and 1.5% had in-hospital death. Within 30 days, 16% of patients had to be readmitted to the hospital -- 6% within 7 days.

I find the study interesting for a couple of reasons. First, I see a lot of patients online who get excited about treatments like CAR-T. They should be excited, in some ways. Early results are very good, and should get even better -- my oncologist said CAR-T will be improved in 5 yars as researchers learn more.

But CAR-T isn't a miracle. It works very well for about 1/3 of patients, pretty well (for about a year) in 1/3, and not at all for the other 1/3. Those numbers should get better. But they aren't there yet. And more importantly, as this study reminds us, EVERY cancer treatment has side effects. And some of them are severe. We have to expect some bad with the good.

Second, I find the cost analysis interesting. Vizient is a company that deals with analytics -- they look at data from clinical trials and elsewhere and help their clients deliver "exceptional, cost-effective care." Their job is to help businesses be successful in helping patients, but also do it for the least money possible. I'm not criticizing Vizient. But the study is a reminder that cancer treatment costs money. One of the big criticisms against CAR-T's manufacturers has been the cost of the treatment. The study is a reminder to me that, as treatments get better, cost is going to continue to be a factor. Patients aren't going to be able to bear that cost, so there will need to be some structure in place that helps them. Health care costs are going to continue to be a political problem. If you're looking for an issue to get excited and involved in, that's a good one.

So CAR-T has certainly given us some success. But like every other treatment, we still have a way to go.



No comments: