Ten years ago, Dr. Stephan Grupp, MD, PhD, launched the first phase 1 trial of Penn-invented CAR-T (chimeric antigen receptor T-cell) cell therapy with 6-year-old acute lymphoblastic leukemia (ALL) patient Emily Whitehead at the Children’s Hospital of Philadelphia (CHOP). After that one CAR T-cell treatment in 2012, Emily has since been free of her leukemia and has remained in remission for more than 10 years.
Now, after a decade of CAR-T therapy, Grupp says that he is finally starting to use the “cure” word.
“We wanted more patients to be out longer to be able to say that thing which we have for a long time called the ‘c word,'” he explained. “CAR T-cell therapy has now been given to hundreds of patients at CHOP, and ― we are unique in this ― we have a couple dozen patients who are 5, 6, 7, 9 years out or more without further therapy. That feels like a cure to me.”
The key to the CAR-T breakthrough with Emily’s therapy was cell proliferation, which had an enduring effect. For Emily and other patients in long-term remission, the modified T cells are still detectable.
“The data that we have from several large datasets that we developed with Novartis are that if you get to a year and your minimal residual disease testing both by flow and by next-generation sequencing is negative and you still have B-cell aplasia, the relapse risk is close to zero at that point,” explained Grupp.
Grupp acknowledged that while the word ‘cure’ is different for everyone, the impact of CAR-T is satisfactory from his perspective. “Oncologists have different notions of what the word ‘cure’ means. If your attitude is you’re not cured until you’ve basically reached the end of your life and you haven’t relapsed, well, that’s an impossible bar to hit. My attitude is, if your likelihood of having a disease recurrence is lower than the other risks in your life, like getting into your car and driving to your appointment, then that’s what a functional cure looks like,” he said.
Read more about CAR-T and Emily Whitehead’s story here.