Keytruda - developed by pharmaceutical giant Merck, which also funded the study - turns off cancer cell's protective functions, letting the immune system recognize and attack the cells.
Doctors have found new ways to use some immune-boosting drugs to fight lung cancer.
Leading researcher of this study, Dr. Leena Gandhi says 'What it suggests is that chemotherapy alone is no longer a standard of care.' she is the Thoracic Medical Oncology Program director for the Perlmutter Cancer Center at the New York University Langone Health.
Results of the study are expected to change how 70,000 patients are treated each year in the United States whose lung cancer has already spread by the time it is found, according to AP.
Patients undergoing the new type of treatment - which harnesses the immune system so it targets and destroys only cancer cells - typically lived longer with fewer reports of the cancer returning.More news: Actor Harry Anderson, of 'Night Court,' found dead at Asheville home
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Gandhi wondered, Would using immunotherapy earlier in treatment, alongside chemotherapy, do more for patients? "And the differences were not small".
Dr. Jorge Gomez, a volunteer spokesperson for the American Lung Association and a medical oncologist and director of thoracic oncology at Mount Sinai Hospital in NY, explained that "about 220,000 patients are diagnosed with lung cancer a year in the U.S.". "We have patients on these immunotherapies alive more than eight years".
For non-squamous non-small cell lung cancer patients, median survival with chemotherapy alone is somewhere around 11 or 12 months, he said.
After a median followup of 10.5 months, those in the immunotherapy group were half as likely to die. Yet, median survival among the study participants who received both immunotherapy and chemo has not yet been reached. I lead the Yale lung team.
Cancer patients should be given immunotherapy as the first line of treatment following the results of "game-changing" trials, charities say.