AstraZeneca (NYSE:AZN) announced a big acquisition deal on Monday. The U.K. drug maker is planning on buying Ardea Biosciences for $1.26 billion in a deal that will expand Astra’s pipeline of new medicines. The deal is in response to stiff competition from companies making cheap generic versions of AstraZeneca’s top-selling drugs. A small, targeted acquisition like this, the company says, will hopefully offset that impact.The biggest part of the acquisition is Ardea’s gout drug lesinurad, which is currently in late-stage trails as a pill. AstraZeneca says it plans to commercialize the drug and sell it in China and Japan. Investors are lukewarm about the acquisition though. Currently, shares of the drug maker are down over 1.5% on the London Stock Exchange.