Indianapolis-based Eli Lilly and Co., looking for every extra dollar it can get before watching its bestselling drug's patents expire next month, might get more sales out of its $2.2 billion-a-year lung cancer drug Alimta.

A committee at the European Medicines Agency issued a positive opinion for the use of Alimta as a "continuation" maintenance therapy, Lilly announced Monday. That makes market approval by the European Commission more likely.

Continuation maintenance approval could mean significantly more dollars for Lilly. It 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.

Receiving approval as a maintenance therapy, which Alimta won back in 2009, helped sales soar 66 percent since then. Alimta sales totaled $1.2 billion worldwide in the first half of 2011.

Alimta already has been growing rapidly in foreign markets, with sales rising more than 17 percent from the first half of 2010 to the first half of this year.

According to Lilly, no chemotherapy is currently approved as a continuation maintenance drug.

"Lung cancer is one of the most difficult cancers to treat, and new therapy options are much needed," 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 opinion of the committee at the European Medicine Agency 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.

Lilly’s U.S. and European patents on its bestseller Zyprexa will expire in October, allowing cheaper generic copies to sap most of the antipsychotic’s $5 billion per year in sales.

Zyprexa will be the second of five Lilly blockbusters to lose 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.