Drugmaker Eli Lilly ( LLY) is looking for acquisitions of as much as $15 billion now that it has digested ImClone Systems, the company's CEO told the Wall Street Journal. In an interview, John Lechleiter said he wants to diversify the company's product lineup to offset revenue declines that some of Lilly's drugs will face in the next several years from competition with cheaper generics, the Journal reports. Lilly's best-selling drug, the antipsychotic Zyprexa, loses patent protection in 2011. Lechleiter ruled out a mega merger like the Pfizer ( PFE) deal for Wyeth ( WYE) or Merck's ( MRK) agreement to buy Schering-Plough ( SGP). He said it's not clear major drug-industry mergers are an advantage, adding he doesn't think the "large-scale consolidations address innovation." The CEO told the Journal Lilly preferred to grow incrementally. Lechleiter said Lilly would pursue acquisitions costing from $5 billion to $15 billion. The company wants to expand its animal-health business and was looking at the biotechnology industry for good values. Lechleiter, in a separate interview with the Financial Times over the weekend, explicitly ruled out a combination with Bristol-Myers Squibb ( BMY), one company to which Eli Lilly has been linked. He told the newspaper he would focus instead on work to boost Lilly's internal development of experimental medicines alongside selective smaller-scale deals.