At two years, 89% of patients in the trial treated with the drug remained alive and disease-free against 53% on placebo.
Tagrisso, which is approved in several countries for advanced or metastatic lung cancer, reduced the risk of disease recurrence or death by 83% in non-small cell lung cancer patients.
Lung cancer accounts for about one-fifth of all cancer deaths, while 85% of diagnosis are non-small cell lung cancer.
"The data from Tagrisso is some of the strongest we’ve ever seen, and the drug has drastically changed the course of disease progression," Shore Capital commented.
Analysts pointed out that this trial could provide an example of how to keeps cancer at bay if it cannot be cured by surgery alone.
Dr José Baselga, AstraZeneca’s vice president for oncology research and development, said the results “provide hope for a cure”, which the broker said is a reasonable statement.
"Of course, the data here aren’t a cure, given 20% of the population after three years had either died or had a recurrence of the disease," analysts said.
"However, it is a significant step in the right direction and one we are very encouraged by."
Shares rose 2% to 8,857p on Friday in early trades.
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