The Value of Reducing CAR-T Treatment Wait Times Among Patients With Diffuse Large B-cell Lymphoma

Alice J Chen, PhD, Sol Price School of Public Policy and Leonard D Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles, CA, analyzed the value of reducing chimeric antigen receptor T-cell (CAR-T) treatment wait times on patients with refractory and relapsed aggressive blood cancer, and found that delays affected access to CAR-T treatments and treatment effectiveness.

Transcript

Hi, my name is Alice Chen. I'm an associate professor at the University of Southern California Sol Price School of Public Policy, as well as a senior fellow at the Leonard D Schaeffer Center for Health Policy and Economics.

I'm very happy to talk to you about our paper, “The Value of Reducing Wait Times for Chimeric Antigen Receptor T-Cell Treatment.” In this paper, we were motivated by thinking about the adoption of new drug technologies, chimeric antigen receptor T-cells, or CAR-T, therapies offer significant survival gains to patients, but the adoption or their use of this technology may be delayed by several different factors.

For example, providers may be hesitant to prescribe the therapy due to concerns over large costs for their patients or high side effects, potential severe side effects. Insurers might be slow to approve the treatment, again, due to high costs. Manufacturers might experience delays due to manufacturing issues and even treatment centers might have delays due to wait times. And so given that there's delays in this process in accessing this really very innovative new drug technology, we wanted to figure out what are the survival costs associated with that delay. And so we've focused, in particular, on KYMRIAH, and KYMRIAH as treated for adult patients with relapsed and refractory diffuse large B-cell lymphoma. And we used data from the JULIET clinical trial, which was used in the FDA approval of KYMRIAH. And what we wanted to do was figure out what would be the cost of the delay. And there are two different sources of this cost.

One comes from the fact that patients who are waiting for the drug are not able to receive it due to death or due to, sort of, severe sickness that they aren't able to tolerate the drug. The second one comes from this idea that patients who have a higher tumor burden or higher disease status have less efficacy from receiving the CAR-T therapy. And so when we think about these two groups, the way we identify their survival costs in the data is by, for the first group by looking at the patients who were waiting and enrolled in the clinical trial but never received the CAR-T therapy. And we have an ability to see, okay, they either died or they weren't able to receive it for some sort of non-mortality reason. For the second group, what we can do is observe the tumor burden progression of patients over time in this clinical trial.

And we measure tumor burden by LDH, which stands for lactate dehydrogenase. It's a well-known, sort of, metric of tumor burden for this population. And we can see that patients who have longer wait times have higher tumor burdens or higher LDH. And we also then use measures of the literature to understand how higher LDH affects survival from having the CAR-T therapy. And so, looking at these two groups and using some sort of econometric modeling methods, we found that if we could reduce wait times by 2 months, the number of patients that are newly eligible for CAR-T therapy would increase by 10.7%. I mean, these are the patients who were never able to receive the CAR-T therapy, due to death or non-mortality reasons. The second group of patients who already received the CAR-T therapy, reducing 2-month rate times for them, generates a 3.3% increase in survival gains per treated patient.

So looking at, sort of, these two groups together, we find that reducing wait times by 2 months can increase treatment efficacy by 14% with about a quarter of the gains going to patients who are able to receive the CAR-T therapy sooner in their disease course. And we think that this study is important because it highlights the cost of delays of accessing CAR-T therapies, in addition to the changes in the treatment effectiveness of the CAR-T therapies. And it has, sort of, strong implications for making sure that patients are able to access the treatment, if eligible, at a faster rate in their treatment plan. And it has implications for insurers, providers, and as well as payers and manufacturers. And I know manufacturers are thinking about how to reduce that 2-to-6-week wait time for the CAR-T therapy. So thank you for listening to this study. I hope you found it informative.