Immunotherapy

What If Your Immune System Could Be Taught to Kill Cancer? Her chart said ‘Two weeks to fatal event.’ Ten years later, she’s still alive.

In principle, immunotherapy is simple. It’s a way to trigger the immune system’s ability to seek out and destroy invaders. That’s how the body fights off bacteria and viruses. But it doesn’t do that with cancer, which occurs when healthy cells mutate to outsmart those built-in defenses. That’s where immunotherapy comes in. “Instead of using external forces, like a scalpel or radiation beams, it takes advantage of the body’s own natural immune reaction against cancer,” says Dr. Steven Rosenberg, an immunotherapy pioneer and chief of surgery and head of tumor immunology at the National Cancer Institute (NCI). These strategies don’t target cancer itself but work on the body’s ability to fight it. These therapies, administered in pill or IV form, trigger the immune system to fight cancer cells while keeping healthy cells intact. For someone as frail as Mike, that was an especially appealing prospect.

In the past decade, scientists have come closer to making a reality of immunotherapy’s promise. Some trials of the latest generation of these therapies have already produced astounding results. In studies of people with certain types of B-cell leukemias and lymphomas who haven’t responded to any other treatment, upwards of 80% of them have seen their cancer disappear. “It’s unprecedented to see these kinds of results in such early trials,” says Dr. Stanley Riddell, an immunotherapy researcher and oncologist working on one of those trials with his colleague Dr. Cameron Turtle at the Fred Hutchinson Cancer Research Center in Seattle.

Market experts estimate that in 10 years, immune-based treatments will generate anywhere from $35 billion to $70 billion a year in sales. That would make immunotherapy by far the most valuable class of medical drugs in history, eclipsing the current record holder, cholesterol drugs like statins. Immunotherapy, which Vice President Joe Biden says could be “revolutionary,” is also central to the Obama Administration’s new “moon shot” to cure cancer.

There are currently 3,400 immunotherapy trials under way in the U.S. and many more around the world. These trials are hoping to prove that immunotherapy is not only a safe but also a better way to battle certain cancers–one that may eventually spare people the life-sapping effects of chemotherapy and the years of follow-up surgeries.

But it also highlights the chasm between the fast pace of scientific progress and the ability to deliver it to the people who need it most. That makes the clash between the priorities of scientists, drug companies, regulators and patients unavoidable–at least for now. Scientists are barreling ahead, trying to make some of the most impressive drugs ever developed. Drug companies are bankrolling many of those studies in the hopes of bringing to market a revolutionary kind of medicine. And regulatory agencies, focused on safety and effectiveness, push for stringent testing criteria that may shut out many patients from early access to experimental drugs.

In the balance are the nearly 7 million people around the world who die of cancer every year. A handful of them may make it into trials and see miraculous results. Others have no choice but to wait.

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