Revenue at Pfizer declined 9%, to $11.4 billion, in the first quarter. Profit proved sicklier, dropping 15%, to $2.3 billion. Analysts had expected better. The earnings underscore how brutal the drug business can be. Having a steady stream of new products and relatively strong patent protections is imperative. If the R&D department has a gap in its output, the executive team better buy something new and promising, which is one of the main reasons Pfizer is keen to acquire AstraZeneca, a British rival that has a robust line of cancer and cardiovascular therapies. Meanwhile, Pfizer said its tax rate is hovering around 25%, presenting another major incentive for its overseas shopping.