Reporting here at the European Society for Medical Oncology Congress, Charles Butts, MD, says that people treated with a lung cancer vaccine survived more than four months longer than those who received only standard cancer therapy.
Though four months might not seem like a long time, these patients had an aggressive disease that would be expected to kill even more quickly, says Butts, a cancer specialist at the Cross Cancer Institute in Edmonton, Alberta.
Even more exciting, he tells WebMD, is that among the subset of patients whose cancer was confined to the lung, nearly twice as many given the vaccine survived for two years compared with those given standard treatment.
"The results speak for themselves," Butts says. "There is a survival advantage that is difficult to ignore. This is huge."
Jose Baselga, MD, chairman of the scientific committee that chose which studies would be presented at the cancer meeting, agrees. "This is groundbreaking, the most important study of the meeting. There's a doubling in survival," he says.
How the Lung Cancer Vaccine Works
Unlike flu and other vaccines, most cancer vaccines under development are not intended to be given to healthy people to prevent disease. Rather, they are being developed to help patients with cancer bolster their immune system to better fight the disease.
In this case, the vaccine targets a specific protein that is altered in many lung cancer cells, encouraging the immune system to recognize the abnormal molecule and attack only those cells that carry it.
As an extra boost, patients are also given a drug that jump-starts the immune system, says Baselga, who is also chairman of oncology at the Vall D'Hebron University Hospital in Barcelona, Spain.
Because the vaccine targets only tumor cells, healthy cells are left unscathed. And that means the unpleasant side effects, such as hair loss and nausea, associated with traditional cancer medications are avoided, he says.
Lung Cancer Vaccine Nearly Doubles Survival
In the study, 170 people with lung cancer were randomly assigned to receive chemotherapy alone or chemotherapy plus the experimental vaccine. The vaccine is given as a shot every week for eight weeks, followed by boosters every six weeks for as long as it continues to work.
The people who received the vaccine lived an average of 17 months compared with 13 months for those who were treated with chemotherapy alone, the study shows.
Among those people whose cancer was confined to the lung, the vaccine is working so well that 60% are still alive two years later, meaning that the researchers can't yet calculate their average survival time. In contrast, patients in this subgroup who received chemotherapy alone survived an average of just 13 months, Butts says.
One patient is still alive and on the vaccine three-and-a-half years after beginning the trial, he says.
Both Butts and Baselga stress that the vaccine is not ready for widespread use. But the results of the trial, sponsored by the vaccine's manufacturers, Biomira Inc. of Edmonton and Merck KGaA of Darmstadt, Germany, are favorable enough that a larger, longer study is expected to begin next year.
"Should these findings be confirmed in the larger trial, this would be a true breakthrough," Baselga tells WebMD.