AstraZeneca's key immunotherapy drug durvalumab has been shown to reduce the risk of stage III lung cancer worsening or causing death in a trial, the pharmaceutical company says.
The trial results are a boost for a product the company hopes will become a blockbuster drug with sales in the billions of dollars.
Astra said it was in active discussion with the authorities over its plans for regulatory submission.
The drug, which will have the brand name Imfinzi, works by helping the body's immune cells kill cancer, offering an alternative to chemotherapy.
The trial found that Imfinzi "significantly reduces risk of disease worsening or death in phase III pacific trial for stage III unresectable lung cancer", meaning inoperable lung cancer.
"These are highly encouraging results for patients with locally-advanced lung cancer for whom surgery is not an option," Sean Bohen, Executive Vice President, Global Medicines Development and Chief Medical Officer at AstraZeneca, said in a statement.
"We look forward to working with regulatory authorities around the world to bring Imfinzi to lung cancer patients as soon as possible."
US regulators earlier this month approved durvalumab as a treatment for bladder cancer, marking the first commercial green light for the product, though its big commercial opportunity lies in previously untreated lung cancer.
AstraZeneca said that it was continuing to explore Imfinzi's full potential both as a treatment by itself, as well as in combination with tremelimumab.
Results of that trial are due in the middle of the year, and could transform AstraZeneca's business.
