The study began as a phase 1 trial to determine the safety profile and tolerated dose of the drug. Because the researchers identified patients who responded positively to the drug, they wanted to find a larger group of patients who tested positive for the gene mutation.
The treatment reduced the tumor size in more than half of the 82 participants, and stopped tumor growth in one third. Historically, chemotherapy only halts tumor growth in 10 percent of non-small-cell cancer patients.
"About 60 percent of people with ALK mutations will have a good response with crizotinib, so for these people, this drug offers a 35 percent better chance for good disease shrinkage," said Dr. Gregory Kalemkerian, professor of Medicine and co-director of Thoracic Oncology at University of Michigan Health System. "That is a big benefit in the oncology world."
Genetic testing is the newest and most sophisticated of techniques to treat a variety of illnesses. The treatments require a direct examination of the DNA itself.
Dr. William Pao, an associate professor of medicine at Vanderbilt University, knows a lot about the topic because of his research on identification of genes in lung tumors.
"We are moving into the era of genetically-informed cancer medicine, where we use the genetic fingerprint of individual patient tumors to customize treatment plans," said Pao. "Many of us in the field are excited about this because we believe that the outcomes will be better and potentially less toxic than what we have done in the past."
Although the proportion of patients who carry the ALK mutation is small, the goal for such treatments is to personalize the delivery of care to patients with lung cancer.
"Though only three to five percent of patients harbor the particular mutation, those patients can receive dramatic benefit," said Dr. Martin Edelman, professor at the University of Maryland School of Medicine. "It must be recognized that a small percentage of a very common disease represents a fairly large number of people."
While the results of the early trials have been promising, researchers have already planned additional trials to confirm the long-term effectiveness of the treatment. The published study only reports the first six months of treatment results. In similar types of therapy, resistance can develop in patients within one or two years.
But for Cogan, the experience is worth the risk. She said she remains optimistic.
"I feel so fortunate to be in this clinical trial and have the wonderful care from the doctors at Mass General," she said.