Posted 11:35 AM 7/19/2012 : Your Healthy Family: Targeted cancer therapy
Physicians at the University of Colorado Hospital are finding startling success with medications that are made to match the genes of a particular lung cancer.
The new strategy means the drugs work only on certain patients - but they can work really well.
Researchers think the cancer-fighting drugs may tamp the disease for a few years, and then the cancers may mutate and find a way around the medication. But years of healthy living is fantastic for people who've been diagnosed with Stage 4 lung cancer, which has a five-year survival rate of less than 3 percent.
Dr. Ross Camidge of UCH says patient Andy Bonnett is a prime example of what one of this new strategy of "personalized medicine" can do.
Two years ago Bonnett was one of those Stage 4 lung cancer patients. He was, said Camidge, "a young man who had never smoked, led a very healthy life, developed increasing shortness of breath and pain, and was diagnosed with lung cancer in his mid-30s."
In treatment, Bonnett was suffering through chemotherapy, so sick and in pain that he did little beyond eat, drink and sleep.
"The chemo was so rough, when I would blink my eyes, the corners of my eyelids would tear," he said. "That's when I stopped chemo."
He was trying alternative medicine when a friend of a friend told him about a then-clinical trial for cancer patients at UCH. Bonnett had to clear his body of all other medications before starting the trial; that period of time proved to be so tough, he was hospitalized.
"I didn't think I'd make it out of the hospital," he said. The tumors were pressing on my heart, it was really painful all the time."
UCH conducted genetic tests to see if Bonnett's cancer had a malfunctioning ALK gene. The new drug, Crizotinib, starves this type of cancer. The doctor was happy to be able to tell Bonnett: "You're not the same as everyone, and we have a drug that works just great on your type of cancer."
"We put him on this treatment [on a] Friday and asked him to email me," said Camidge, who heads the thoracic oncology department at the hospital. "By Sunday, he stopped painkillers. And by Monday, he went hiking."
"That was two years ago, and he's still giving me a lot of cheek and doing very well," said the Oxford-educated Camidge.
Bonnett, now 36, seems determined to push the limits of his restored health. "I can run without nausea and throwing up, ride a mountain bike, snowboard, ski, hike, pretty much anything that I used to do, and sometimes more," he said.
Recently, he surfed for his first time on the Outer Banks of North Carolina with First Descents, a Colorado-based program for cancer fighters and survivors. "It was the most powerful experience I ever had," Bonnett said. It wasn't just getting hooked on surfing - it was bonding with new friends who've had exactly the same experience of fighting for their lives.
UCH, in Aurora, moved in this new direction of cancer treatment when several lines of research dovetailed. UCH was doing clinical trials on the new drug, Crizotinib. Then the journal Nature reported that in some lung cancers, the cancerous cells grew uncontrollably due to a gene mutation called ALK.
UCH found a way to test its patients' tumors for that mutation. Soon, Camidge and his colleagues saw that the five percent of lung cancer patients who had that ALK mutation were the ones responding well to Crizotinib.
So UCH changed the way it treats lung cancer.
Traditionally, physicians had to guess which of many cancer treatments to try on a patient. Now, UCH recommends testing all lung cancers tissues at the molecular level, so each patient can be targeted with the medication that will work best on his or her particular cancer.
But this wasn't just a successful new drug. This line of research opened a window of understanding. Lung cancer is actually a number of diseases. And that is why some medications and chemotherapy worked on one patient and not on another.
UCH now is the leader and only Colorado member of the Lung Cancer Mutation Consortium, a national network of 14 research centers determining which medications work on which subtypes of lung cancer, said UCH spokesman Dan Weaver. In addition, other research centers are trying genetic testing on melanoma and colon cancer.
The downside to this progress? Crizotinib costs $115,000 a year. Manufacturer Pfizer does have special programs to help patients afford the medication, which is now approved and sold under the brand name Xalkori.
Bonnett continues to down six Crizotinib pills daily. For two and a half years, he has been tumor-free. "This targeted treatment has been absolutely phenomenal. I almost forget that I have cancer a lot of the time, and that blows me away."
Recently, however, Bonnett started showing signs that his cancer is mutating, and developing resistance to Crizotinib. His doctor was not surprised.
"Over time, evolution takes place, and it will find a way around whatever block we place," Camidge said. "Then we have to re-biopsy, re-test and if possible, change the treatment to keep up with it."
Bonnett will soon start that process, with a biopsy, a molecular examination of the tumor, and a new drug that also targets the ALK mutation. He is excited because the new drug has shown stronger results.
"It's a constant war with cancer. As it adapts, we have to adapt with it," Camidge said. "The cancers, we are starting to find out, are as different as the individuals that are harboring them."
For more information on UCH's lung cancer program, call 1-866-407-6621.