A promising new set of cancer drugs has one big catch
New drugs promise a significantly increased the chance of living longer compared to chemotherapy, but they don't work for everyone yet
There's a promising new field of medicine that's making a huge difference in the way we treat cancer: It's called immunotherapy — a way of manipulating the immune system so that it has a better shot at killing cancer cells.
But as with many medical advances, it will take doctors and scientists a long time to deliver anything that actually makes a difference for most patients. At times, the progress can seem painfully slow.
In an opinion piece published this week in The New York Times, Matt Jablow wrote about his wife's experience on a promising immunotherapy drug called Opdivo, which unexpectedly failed a key cancer trial and failed for Jablow's wife as well, who had been diagnosed with Stage 4 lung cancer. She died last year.
This year, Jablow wrote, he was upset when he encountered a commercial that featured healthy, smiling families and touted Opdivo as "significantly increasing the chance of living longer versus chemotherapy." In his op-ed, Jablow pointed to a big catch with these promising new therapies that's often overlooked: Immunotherapy drugs don't work for everyone yet. Sometimes they don't even work for most patients.
Even in more successful, earlier trials, less than 20 per cent of patients saw improvements when taking Optivo.
"Immunotherapy is an exciting development with the potential to significantly extend the lives of thousands, perhaps millions, of patients," Jablow wrote. "But right now, the hype far exceeds the reality. The drugs are expensive and their efficacy, as shown by the Opdivo trial, is far from guaranteed."
In response to Jablow's piece, a spokeswoman from Bristol-Myers Squibb, the makers of Opdivo, provided this statement via email: "As the leading cause of cancer death in the US, lung cancer is an aggressive, highly-stigmatised, difficult-to-treat disease with a high mortality rate, continued unmet need and limited advancements in treatment over the past decade. Bristol-Myers Squibb is dedicated to patients first and foremost, and we are focused on educating patients, families and communities, particularly as new and different treatment options become available."
Other immunotherapies have similar problems, and researchers are trying to figure out how to get more people to respond to treatment.
Take Keytruda, the drug that's credited with helping get President Jimmy Carter cancer-free after he was diagnosed with melanoma that had spread to his liver and brain. Only about 30 per cent of metastatic-melanoma patients using Keytruda alone respond completely. That's still better than the average response rate of chemotherapy treatments on their own in cases of metastatic melanoma, but it's not 100 per cent.
That's why companies think the solution may lie somewhere in combining an immunotherapy with other drugs, a proposition that could get expensive. These drugs can often cost thousands of dollars a month. Add that to another drug, and the cost for such good results is a bit staggering.
Trials are already being run for combinations of two and even three immunotherapies at the same time. Beyond that, companies are looking at ways to pair drugs together to help them work better.
For example, drugs that target the programmed cell death 1 (or PD-1) receptor to essentially take the "foot off the brake pedal" in the immune system might be put together with other immunotherapies that activate the immune system in different ways. Or, those PD-1 inhibitors might be matched up with targeted chemotherapies, or other tools in the cancer-treatment toolbox.
For now, cancer immunotherapy is just starting to pick up speed. But for many patients, these advances won't come quickly enough.
