INDIANAPOLIS (AP) ¿ Eli Lilly & Co. is ready to buy again, four months after closing its largest acquisition ever, the $6 billion-plus purchase of cancer drug maker ImClone Systems Inc.

Lilly Chief Executive John Lechleiter told The Wall Street Journal his company will pursue deals that cost between $5 billion and $15 billion but will shy away from bigger acquisitions.

The company also plans to stick to drugs, Lechleiter told the Journal, saying Lilly isn't interested in medical device or diagnostic companies.

He said Lilly wants to expand its animal-health business and also will consider the biotechnology sector.

A run of major deals has swept through the drug industry this year. New York-based Pfizer Inc. said in January it agreed to buy Madison, N.J.-based rival Wyeth for $68 billion.

Swiss pharmaceutical giant Roche paid $46.8 billion in cash to buy the 44 percent of California-based biotech pioneer Genentech that it didn't already own.

Whitehouse Station, N.J.-based Merck & Co. will pay $41.1 billion to buy Kenilworth, N.J.-based Schering-Plough Corp.

But the Journal reported that Lechleiter ruled out deals that large. "There's no evidence that a consolidated industry is a more productive industry," he said.

The CEO said he wants to diversify Lilly's product portfolio as the company prepares for a wave of patent expirations that will hurt revenue.

Lilly will lose patent protection for its best-selling drug, the antipsychotic Zyprexa, in 2011. Then patents for its next three highest-selling drugs ¿ Cymbalta, Humalog and Gemzar ¿ are set to expire in 2013.

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