Indianapolis-based Eli Lilly and Co. said Friday that it has received European approval to use its lung cancer drug Alimta as a continuation maintenance therapy, potentially giving one of Lilly’s rising stars a new boost in sales.

That’s key for Lilly, which in September and October watched its European and U.S. patents expire on Zyprexa, its $5 billion-a-year drug.

Alimta’s sales have been growing fast, particularly in overseas markets. The drug’s revenue has grown 11 percent this year and is on pace to top $2.4 billion.

Continuation maintenance would allow doctors to treat lung cancer patients with Alimta during initial treatment and for numerous months afterward to keep the disease in check.

Alimta already was approved as a maintenance drug, but only for use after initial treatment of the disease with other drugs. According to Lilly, no chemotherapy is currently approved as a continuation maintenance drug.

Receiving approval as a maintenance therapy, which Alimta won back in 2009, helped sales soar 66 percent since then.

“With Alimta continuation maintenance therapy, patients with lung cancer who have already benefited from first-line treatment will now have the option to continue treatment with Alimta, with the goal of a better clinical outcome,” said Dr. Allen Melemed, Lilly’s senior medical director for Alimta.

Alimta is designed to treat patients with non-small cell lung cancer who have a certain tumor type called nonsquamous. The decision by regulators at the European Commission was based on a clinical trial, the results of which were presented publicly in June. The trial treated patients with a combination of Alimta and cisplatin, a standard chemotherapy for lung cancer, and then those who did not improve received maintenance doses of Alimta.

Zyprexa, an antipsychotic medicine, was the second of five Lilly blockbusters that are losing patent protection between 2010 and 2014, and the company has not been able to launch new drugs with strong enough sales to replace that revenue.

So Lilly leaders have looked to winning extra indications for its existing drugs, such as Alimta, while also growing its businesses in animal health and emerging markets. It hopes those efforts produce enough revenue to give its research and development team time to launch new drugs.