An experimental lung cancer pill from AstraZeneca delays disease progression by more than a year, according to new data presented at a medical meeting on Friday. 

AZD9291, which the company expects to file for U.S. approval in the second quarter of 2015, is one of a number of cancer medicines AstraZeneca is hoping will rebuild its sales following patent losses on older drugs.

An analysis presented at the European Lung Cancer Conference in Geneva demonstrated a median progression-free survival for patients on the drug of 13.5 months.

AZD9291, like a rival product in development at Clovis Oncology, targets a genetic mutation that helps tumors evade current lung cancer pills, including AstraZeneca's own established product Iressa.

During its defense against a $118 billion takeover attempt by Pfizer last year, AstraZeneca said it believed AZD9291 could sell as much as $3 billion a year.