So is Lilly’s $6.5 billion deal to buy ImClone Systems too risky? The acquisition will drain billions in cash and force the drugmaker to take on billions more in debt during a worldwide credit crisis. Lilly’s stock fell 24 percent over five days after the announcement, The Indianapolis Star notes.

But John Lechleiter brushes off criticism that the move is too risky. “This is what we do every day,” he tells the paper. “We place risky bets on our pipeline. This is what our shareholders expect us to do.” A bigger risk, he argues, would be to do nothing and watch Lilly’s patents begin to expire on blockbuster products, such as Zyprexa and Cymbalta, and say goodbye to their billions in annual revenue.

The ImClone deal, Lechleiter continues, is part of a long-term strategy to increase Lilly’s role in oncology, seen as a growth market as people live longer and demand more expensive, life-extending drugs. “I’ve learned in 29 years here that we at Lilly and in the industry are sometimes not very good at guessing,” he tells the Star.

The deal, Lechleiter adds, should bolster Lilly’s presence in biotech, where he wants to quadruple the pipeline. And Lilly has plenty of money, he maintains - about $5 billion last year in operating cash flow - to make other deals and handle any emergencies that might come up. “It’s not a bet-the-farm deal by any means,” he insists.

Still, his chief financial officer, Derica Rice, acknowledged that Wall Street is focused on strong balance sheets and plenty of cash on hand in these days of tight credit markets. Moody’s placed Lilly’s Aa3 long-term rating under review for possible downgrade, prompted by the material increase in Lilly’s debt, especially relative to ImClone’s modest level of free cash flow.