NEW YORK (AP) Pfizer Inc. may be the world’s biggest drugmaker, but new CEO Ian Read is taking charge at a trying time for the company, and he will have to deal with a declining share price, repeated failures of potential new products and expirations of patents on key drugs.

Pfizer said on Sunday that Read is replacing Jeffrey Kindler, who was Pfizer’s CEO for four-and-a-half years. Read, 57, has worked at Pfizer for more than 30 years in a variety of positions and countries, making him a potential contrast to Kindler, who was an executive for McDonald’s Corp. and a director of the New York branch of the Federal Reserve before he joined Pfizer.

While Kindler’s exit came as a surprise, analysts said the choice of Read indicates big changes are not immediately in store for the company.

Still, control of Pfizer could be shifting. Read is likely to have less say in Pfizer’s direction than Kindler did because, unlike Kindler, he won’t be the chairman of Pfizer’s board. However Read is getting the newly created role of company president.

Jefferies & Co. analyst Jeffrey Holford said Read is “a safe pair of hands”, who is familiar with Pfizer.

“We are confident that the transition will be smooth and likely beneficial to the company as it becomes increasingly diversified, given Mr. Read’s extensive experience with the company’s key operations,” he said in a note to clients.

But are larger changes needed? In late 2011, the patent on Pfizer’s best-selling drug, the cholesterol medication Lipitor, will expire. Lipitor brings Pfizer almost $13 billion in annual sales, and after the patent expires, generic competition will reach the market and sales of its drug will plunge.