PFE) Lipitor in a head-to-head clinical trial, dubbed Saturn. AstraZeneca had hoped the trial would differentiate Crestor and eat into Lipitor's $12 billion in sales. While the Saturn trial showed Crestor had a "numerically greater" reduction in artery-clogging plaque in patients compared to Lipitor, the results were not statistically significant. A secondary measure did show Crestor had a statistical significance over Lipitor, AstraZeneca said. AstraZeneca shares trading in London were down nearly 3%. -- Written by Robert Holmes in Boston. >To contact the writer of this article, click here: Robert Holmes. >To follow Robert Holmes on Twitter, go to http://twitter.com/RobTheStreet. >To submit a news tip, send an email to: email@example.com.