Another case at Yale involved Colleen Platt, 65, a real estate agent from Torrington, Conn., who was being treated by Dr. Kluger for late-stage kidney cancer. Ms. Platt opted for a clinical trial involving two immunotherapy drugs, atezolizumab and a second drug that Dr. Kluger declined to name because the trial is continuing.
Days after the second treatment in November 2014, Ms. Platt started feeling dizzy and numb and was vomiting water. She went to Dr. Kluger’s office, where they did lab tests that “were so profoundly abnormal, we thought this was lab error,” Dr. Kluger recounted. “We thought the machine was messed up.”
The tests were right. Like Mr. Peal, Ms. Platt had gone into diabetic ketoacidosis, a condition in which her body, desperate to compensate for energy it was missing when her pancreas shut down, created a flux of acid that could keep her functioning in the short term, at the risk of gravely harming organs throughout her body. Outside the emergency room, while a chaplain visited Ms. Platt to comfort her, Dr. Kluger called the drug company to report the extraordinary reaction.
Today, like Mr. Peal, Ms. Platt takes multiple insulin shots each day, and still her sugar level fluctuates wildly. On the other hand, immunotherapy has largely beaten her cancer. In fact, after consulting with other doctors and one of the drug companies, Dr. Kluger recommended Ms. Platt continue with treatment, which she did.
“Her pancreas isn’t coming back,” Dr. Kluger said, referring to the diabetic effects of immunotherapy. “She has her life.”
Mr. Peal — who, like Ms. Platt, agreed to let Dr. Kluger and Dr. Herold discuss his case — feels the trade-off will be well worth it. In fact, on Friday, he got the results from a scan taken the day before and learned that immunotherapy had eliminated two of his cancer lesions and shrunk two others. “I can deal with diabetes,” he said, “if I can beat melanoma.”
‘Nature of the Beast’
Evidence of these challenges is decades old.
In the mid-1990s, Matthew Krummel, a young immunology graduate student known as Max, worked at a lab at the University of California, Berkeley, that would become one of the most influential in the development of immunotherapy. The lab was run by Dr. James Allison, who, along with Dr. Krummel, published a seminal paper in 1995 showing that they could eliminate tumors in mice by turning off a brake on the immune system.
But the lab got less attention for a related experiment: The skin of some mice treated this way turned from black to white. They had lost their pigmentation, a result of the immune system’s attacking the cells that make melanin. The startling change was not life-threatening but indicated the power of tinkering with the immune system.
This discovery was novel but not particularly celebrated compared with the promise of curing cancer, Dr. Krummel recalled. The skin study “was kind of a footnote,” he said.
Then came the TeGenero tragedy in 2006.
TeGenero Immuno Therapeutics designed a drug to stimulate the immune system to fight leukemia. At Northwick Park Hospital in London, a Phase 1 trial took place, with six healthy patients getting the drug. Within hours, all suffered multiorgan failure.
The devastating results tempered the enthusiasm and suggested that more work needed to be done in advance of human trials. But enthusiasm came roaring back. Part of the reason was that, ultimately, the autoimmune reactions were seen not only as an acceptable cost of these drugs but as evidence they were working.
“It’s the nature of the beast,” said Martin Bachmann, a professor and immunologist at the Jenner Institute, which is affiliated with Oxford University. “I’m not sure you can get rid of the side effects — it’s really what you want.”
Chemotherapy, too, has side effects, but Dr. Kluger prefers immunotherapy’s trade-offs because the drugs may offer enduring control of cancer without the need for continued treatment. So she is joining others looking to address largely unanswered questions: Who is likely to be at risk, can the side effects be recognized before turning dangerous, and how should they be treated?
In June, Dr. Kluger and Dr. Herold submitted a grant proposal to the National Institutes of Health to study whether they could predict which patients would develop these symptoms. They based the proposal on a hypothesis that some patients have a biology or a genetic background that might make them more likely to have side effects. The proposal has not yet been funded.
Thus far, only a modicum of work has been done on these questions. Several studies found that older mice were more susceptible than younger mice to autoimmune reactions; another study, also in mice, found that obese subjects were more likely to have adverse effects.
“Old or fat mice were literally dead within hours,” said Dr. Murphy, the professor at Davis who believes too little is being done. He is well positioned to see the trends: In the past year, he sat on eight government grant review committees focused on immunotherapy, and he said only three out of 500 research proposals he reviewed focused on the toxicity side of immunotherapy.
Part of the problem, he said, is that the drug companies that are driving research prefer working with labs that support trials’ moving quickly. As a result, Dr. Murphy said, human trials are advancing faster than the background research can be done.
Hoping to push access to lifesaving drugs, the Food and Drug Administration has a “breakthrough therapy designation” that allows faster approval. Since 2012, the agency has granted breakthrough designation about 110 times, almost a quarter of them for immunotherapy.
“When people talk about moonshots, they’re talking about curing cancer, but it has to look at the whole picture,” Dr. Murphy said.
With so much momentum pushing for a cure, the emphasis from researchers and front-line oncologists is on more vigilance about the side effects. Dr. Timmerman, from U.C.L.A., said he wished he had seen the signs of trouble in his patient, who survived cancer only to die in the emergency room after exhibiting seemingly modest flulike symptoms.
“If we had only known the power we had unleashed that was causing such a toll on her organ system, we might have saved her,” he said.
“You have to manage this hour by hour,” he added. “Minute by minute.”