An immunotherapy treatment helped significantly boost survival rates among patients suffering from advanced lung cancer, according to the results of a clinical trial cited by researchers on Saturday.
Almost 25 percent of patients who received the drug pembrolizumab and had not previously received chemotherapy were alive after five years, said the study which was presented at annual meeting of the American Society of Clinical Oncology.
The figure dropped to just over 15 per cent for patients who had previously received chemotherapy.
"The uniformly negative outlook that has been associated with a diagnosis of advanced non-small cell lung cancer (NSCLC) is certainly no longer appropriate," said lead author Edward Garon, an associate professor at UCLA.
The five-year survival rate was 5.5 per cent in the pre-immunotherapy era.
Unlike chemotherapy, immunotherapy works by leveraging the body's own immune system to fight disease.
In this case, the drug acts by turning off a brake in the immune system, a protein called PD-1, which then allows cancer-fighting T-cells to attack faster and more effectively.
"I describe it as sort of changing the thermostat, in terms of how willing the immune system is to tolerate something versus reject it," Garon told AFP.
David Graham, an oncologist at the Levine Cancer Institute in Charlotte, North Carolina who was not involved with the study, said: "It's truly remarkable that for more patients than ever before, we no longer have to count survival in months.
"However, we still have a long way to go to improve outcomes for all NSCLC patients."
According to Garon, the trial proved there are groups of patients "who do have long-term survival prospect, and that does change the way we talk to our patients about the disease."
Moving forward, his team would like to identify other biomarkers to target to further improve survival rates.
"I think we're all hopeful that these are the early days of immunotherapy," he told AFP.
"But I think what this indicates is that even in those early days, there are clear instances in difficult diseases where we can really transform the management of the diseases."