Maximilian Koch, MD, a postdoctoral scholar in the Heitzeneder Lab at the Stanford Cancer Institute, was recently named to Forbes’ 2026 30 Under 30 Europe in Science & Healthcare for his advancements in genetic engineering to accelerate pediatric cancer treatment. We caught up with Koch to talk about his path from a science-obsessed kid in Bavaria to a Stanford researcher preparing to publish a paper on a new CAR-T cell discovery, and how a background in the decathlon and a love for heavy metal guitar riffs keep him grounded outside the lab.

The following Q&A has been lightly edited for readability and length.

Could you start by introducing yourself and sharing what you do at Stanford?

I'm a postdoctoral scholar at Stanford. I'm originally from Bavaria, that's where I went to medical school and also started my clinical training as a resident in pediatric oncology. I paused my residency to do full-time research here at Stanford. Now I've been here for one and a half years in the Heitzeneder Lab, as part of the Stanford Cancer Institute, developing and doing research on cellular immunotherapies.

Do you remember early on in your life when you were first excited about science? Is there a key moment or memory that sticks out to you?

I know that I've been fascinated by all kinds of sciences, actually, since I was a small kid. I read books about the universe, plants, and animals, and I was always so into the fine details. Later in high school, I was heavily drawn to chemistry, especially cellular biology and molecular structures.

After graduating from high school, I knew that I wanted to become a scientist or study the natural sciences. But then I did a year of voluntary work, spent half a year working in a hospital, and that's when I realized that I also really enjoy clinical work. I became interested in delivering an immediate benefit to patients and having that direct human impact. That's why I chose the more challenging path of medical school instead of studying straight biology. I wanted to do both, and I was confident that this choice would perfectly serve my future goals.

What about cancer care sparked your interest, and what keeps you motivated?

For cancer, it's the molecular mechanisms. They play a role in all diseases, of course, but in cancer, they are studied in some of the most detailed ways. I think the oncology field has advanced among the furthest in terms of understanding these processes and learning how to interfere with them to provide a therapy.

My main motivator is to improve treatments for children with cancer. It's a pity that most major scientific advances are applied to adults first, and it takes a few additional years for those therapies to become established for pediatric patients.

We need to make these therapies less toxic, less exhausting, and far more durable. Current chemotherapies can successfully cure a child's cancer, but they can cause chronic health complications or secondary malignancies 10 or 20 years down the road. Even though diseases like pediatric leukemia have high cure rates now, we have to think long term about the consequences of the cure.

What was the path that brought you to Stanford, and what inspired your research focus?

During medical school, I entered a specialized research program for my doctorate. That's when I really got into science and received my formal scientific training on top of my clinical education.  

I studied CD8 T cells, a subset of immune cells, and their response to a bacterial infection called Helicobacter pylori. We discovered that these CD8 T cells promote protection against the infection, and this protection is exclusively dependent on the recognition of one specific sequence inside a single protein of the bacterium. In other words, parts of the pathophysiology of the disease, and even the clinical outcome, could be nailed down to a relatively simple molecular interaction between the antigen and the receptor.

This discovery took years to develop, and it taught me that if you can truly understand a molecular mechanism, it can eventually be translated into something clinically meaningful. I became completely intrigued by T cells and fascinated by their biology and what they are capable of doing. 

Now, I'm engineering these cells as a therapeutic agent against cancer. I chose Stanford because it features the amazing Center for Cancer Cell Therapy led by Crystal Mackall, MD, as well as my lab’s principal investigator, Sabine Heitzeneder, MD, who both have extensive backgrounds in cellular therapy. It is simply the best place to be for this kind of research and training.

What is a current Stanford project you'd like to highlight?

We have a study under review that focuses on CAR-T cell therapy, which is a cellular immunotherapy where a patient's T cells are genetically equipped with an engineered receptor that directs them to target a specific tumor antigen. 

What we discovered is that the endogenous, native immune system of these patients actually mounts an adaptive immune response against the CAR transgene itself. Essentially, the body's natural defense system gets confused and accidentally fights off the same medicine meant to save it. This leads to a loss of the CAR-T cells and renders the therapy ineffective. Despite repetitive infusions, the CAR-T cells disappear because the patient's own immune system eliminates them. This immunogenicity, or ability to trigger an immune response, is at least one major reason why the treatment eventually fails. It hasn't really been widely acknowledged as a problem before, so we were surprised by just how powerful the host immune system is in rejecting the applied therapy.

What are some of the broader implications of this study?

There are three main implications. First, when designing a cellular therapy, you absolutely have to consider the immunogenicity of whatever you introduce. When we engineer T cells, we introduce a new gene encoding something unfamiliar to the human body. We need to make sure future designs are less immunogenic, for example, by making sure they aren't completely synthetic or derived from other animals like mice.

Second, we have to think about stealth approaches. There are potential ways to engineer concealment of the CAR’s immunogenic parts from the native immune system.

The third implication centers on the treatment regimen itself and optimizing how we apply immunosuppression. Right now, patients undergo a process called lymphodepletion, where they receive light chemotherapy before the infusion to clear out circulating T cells and create physical space for the CAR-T cells to grow. Our data supports a new look at this. 

Lymphodepletion could actually delay the development of the anti-CAR immune response because the specific naïve T cells that would mount the rejection are temporarily depleted. Mechanistically, the infusion of a CAR-T cell product can inadvertently act like a vaccine, causing the patient to become vaccinated against the cancer therapy. We want to find ways to suppress and mitigate that specific reaction.

To take a step outside of work, what do you do for fun? How do you spend your time outside of the lab and clinic?

First of all, I do a lot of sports. Back in high school in Bavaria, I competed in track and field, specifically the decathlon. Sprinting and jumping were my absolute favorites, especially high jump, long jump, and pole vault. Competing in the decathlon got me used to exercising on a daily basis. Here at Stanford, I run a lot and do calisthenics, which is bodyweight exercises. No matter how stressful the day was, if I can close it with a workout, I can release all the pressure and clear my mind.

Beyond that, I play the guitar — classic rock, and a lot of heavy metal. I just play for fun. It has some meditative effect on me. It just keeps my mind busy with guitar riffs.

I also really like to travel and discover new places. Being here in the Bay Area feels like being on vacation all the time. As soon as I have days off, I explore areas I haven't been to yet. Next week, I'm actually traveling up the Cascade Range Mountains.

You were recently named to the Forbes 30 Under 30 list. Was that a surprise to you? 

Oh, it was definitely a surprise. I mean, I knew I was 29, so technically under 30! But I wasn't expecting them to acknowledge my achievements or my mission in that way, or that my path would impress them enough to put me on the list. I really appreciate the recognition, but that type of acclaim isn't my core motivation. I just hope that this kind of platform can ultimately support me in reaching my clinical goals.