Bringing Cell Therapy From Oncology to Autoimmune Disease Will Present New and Unique Challenges

Peter A. Merkel, MD, MPH
Credit: Penn Medicine

This is the second part of an interview with Peter A. Merkel, MD, MPH. For the first part, click here.

As chimeric antigen receptor T-cell (CAR-T) therapy and other advanced cell therapy modalities are carried over from use in the field of oncology into the early stages of clinical trials for autoimmune disease, there are important challenges to consider. For example, there may be new safety risks when using these therapies in patients with autoimmune diseases, and the rarity of these diseases may make recruitment efforts for clinical trials difficult.

At the Cell Therapy for Autoimmune Disease Summit, held from November 28-30, 2023, in Philadelphia, Pennsylvania, CGTLive® spoke with Peter A. Merkel, MD, MPH, the chief of the Division of Rheumatology and a professor of medicine and professor of epidemiology at Penn Medicine, to learn more about this topic. He emphasized the importance of doing the work to overcome these challenges appropriately, but also expressed optimism about the potential benefits of cell therapy in autoimmune disease.

CGTLive: What are some of the challenges of bringing cell therapy to autoimmune disease?

Peter A. Merkel, MD, MPH: There are several. Some of these diseases are not particularly common or not highly common. Will we have enough patients that are appropriate?—because again, we're selecting carefully for patients that are appropriate to try an experimental therapy, but for which the risk is reasonable. For them, and for us, we want to make sure that we're safe. If there's a lot of companies involved in trying to do it, are we spreading too thin? Are there enough patients to go around to make this appropriate? I think the other thing is, what are the risks? What are the unknown risks that we don't know about? We have to be careful, we have to make sure we know that this is a therapy that has been applied from oncology now to a new area of disease. So we need to learn: Are there new risks that we don't know about?

This is also economically challenging. These are expensive therapies. I think there's a return on an investment so to speak [because] I think that having these chronic diseases is also costly, and I think the costs [of the cell therapies] will come down—but there are concerns.

And of course, there's this trade off of upfront risk versus long-term benefit. I think there's a concern, as I mentioned, with the challenges of study design—how do you do this, to be able to get a proper answer?

Are there any area of interest for further research in this area that you can discuss?

It's kind of an open question. I think what's exciting here is there are multiple different pathways, or at least multiple different programs that are being developed, that are looking at different aspects of immunology—different pathophysiologies and different targets, whether it be CD19-directed CAR-T, whether it's autologous or allogeneic, is it RNA technology, is it T-regulatory cells, is it bispecific?—there’s just a remarkable array of different ways to think about cell-based therapy. I think that's great. It's fascinating immunologically. Let's make sure we do it right—choose the right ones for the right diseases—and go forward. I think we'll learn a lot about the immunology of our diseases by carefully studying with our patients at the same time.

Is there anything else you’d like to share with the audience?

I think there’s an excitement, but a cautious optimism about this area. I think we are certainly hopeful that some forms of cell-based therapy will help some forms of autoimmune disease and hopefully substantially. We need to do this right, we need to move it forward, but I think we're very enthused. We need to see how this plays out and this will take some time. I also think patients will be interested. We need to remember that the goal is to help patients and that's what we're trying to do. We want to be able to raise the bar and help our patients even more than we’ve been able to so far.

This transcript has been edited for clarity.