How scientists built a ‘living drug’ to beat cancer

IN 2010, EMILY Whitehead was diagnosed with Acute Lymphoblastic Leukemia, a cancer of certain cells in the immune system.

THIS IS THE most common form of childhood cancer, her parents were told, and Emily had a good chance to beat it with chemotherapy. Remission rates for the most common variety were around 85 percent.

It would be 20 months before they’d understand the shadow behind that sunny statistic, and the chilling prospect of volunteering their daughter as patient zero for the world’s first living drug.

Emily started on the 26-month chemotherapy regimen. She lost her hair and most of her kid energy, and the curative poison seemed to be doing its job, sickening her body as it killed the disease. But her cancer, like all cancers, was alive, a constellation of mutant cells that continued to mutate into new variations. Some of these new mutants were immune to the chemotherapy and continued to thrive.

By October 2011, Emily had relapsed; in the language of immunotherapists, her cancer had “escaped.” Her physicians at Pennsylvania’s Hershey Medical Center could only offer more chemo, more aggressively. In February 2012 she relapsed again.

Now it was painfully obvious that Emily was one of the 15 percent of kids with leukemia for whom chemotherapy did not work. The cancer was doubling daily in her bloodstream, and it was too late for a bone marrow transplant—she was too sick. Oncologists now referred to Emily’s cancer as “terminal.” She was 6 years old.

Cancer is shitty and unfair, but that shitty unfairness reaches a whole other level when it happens to a kid. Tom and Kari Whitehead were told that they needed to consider hospice for their daughter. Or, if they wanted, she could die at home. Traditional medicine had nothing else to offer her. But a researcher at the Children’s Hospital of Philadelphia might, if Emily’s parents were willing to take the risk.

The Whiteheads learned of this possibility on a Sunday. By Monday, they were in Philadelphia. Emily Whitehead would be the world’s first kid to try an experimental cancer therapy, called CAR-T. Researchers were offering to reprogram her immune cells into a clone army of cancer-targeting serial killers.

A CAR-T CELL is a reengineered T cell that has been removed from the cancer patient, tweaked in the lab to recognize that patient’s cancer, and then injected back into the patient. Because each of these reengineered cells is a monstrous robocop-like assemblage of immune cell parts, researchers had given their invention the equally monstrous name of “Chimeric Antigen Receptor T cell” (in Greek mythology, the chimera is a patchwork monster combining aspects of a lion, goat, and serpent), but “CAR-T” sounds much better.

CAR-T is often called the “most complex drug ever created,” but it is not really a drug in the traditional sense. Unlike an inert molecule introduced to the body for some temporary effect, CAR-T is alive. If it worked as designed, this “living drug” would go on living in Emily’s bloodstream like a cancer-killing superpower, providing her with a sort of immunity against her disease. And in the process, it would give humanity a revolutionary new weapon in the war on cancer.

And if it didn’t work? If the unleashed cellular serial killers turned on the girl’s healthy cells instead of the cancer? Well, the Whiteheads decided, best not to think about that. At this point, their only daughter had nothing to lose.

There is a lot more to this story, which can be found here: https://www.wired.com/story/how-scientists-built-living-drug-to-beat-cancer/

A SINGLE CAR-T cell can take out as many as a hundred thousand cancer cells and produce freakishly rapid remissions that take even the most ardent immunotherapist by surprise. Sadelain calls them “a living drug.” June sometimes refers to them as “serial killers” of cancer.

Only four weeks after her first CAR infusion Emily’s lab results showed no incidence of cancer—a lab error, obviously, so June ordered a second biopsy. But there was no error. The procedure had been a success—as a drug for Emily and as a proof of concept. That was good, but not the end. Emily wasn’t the only childhood leukemia patient to receive the experimental treatment.

June had also treated another juvenile ALL patient at Children’s Hospital, a 10-year-old girl. Her leukemia had responded to the CAR-T therapy, and she had gone into remission, only to relapse two months later.

Biopsies showed that this girl’s leukemia had mutated and escaped on B cells that did not carry the CD19 target protein. The cancer had changed uniforms, but they didn’t have another CAR to give her.

And so in September 2012, Emily Whitehead returned to school with a sick note signed by President Obama, a cute national success story celebrated on Good Morning America as proof our progress against cancer. The other girl died of her disease, a sad and humbling reminder of the work yet to be done.

The whole story can be found here: https://www.wired.com/story/how-scientists-built-living-drug-to-beat-cancer/