Shares of AstraZeneca PLC fell Friday after a study meant to show its cholesterol drug Crestor was better at preventing plaque buildup in heart arteries than rival drug Lipitor found no clear advantage for its drug.
THE SPARK: The study compared Crestor with Pfizer Inc.'s Lipitor in high-risk patients with hardening of the arteries, a condition that can cause strokes or heart attacks. Astrazeneca said preliminary results indicated Crestor showed a greater percentage reduction in the volume of plaque in coronary arteries, the study's main goal. But the result was not statistically significant, meaning it could have occurred by chance. The study did produce a statistically significant reduction in a secondary goal, reduction of total plaque volume.
THE BACKGROUND: AstraZeneca was gambling that the study would show Crestor was better than Lipitor, the world's top-selling drug. That would have given the British drug maker a strong argument that doctors and patients shouldn't defect from Crestor to generic Lipitor when it becomes available on Nov. 30, offering big savings.
THE ANALYSIS: In missing the primary endpoint, the data has not provided the clear positive result that AstraZeneca could have used to continue arguing Crestor is superior to Lipitor, Jefferies & Co. analyst Jeffrey Holford wrote.
Conversely, he wrote, the positive trend and statistical significance achieved in the secondary goal that the results were not a clear negative for Crestor.
Holford wrote that the arrival of generic Lipitor will likely continue Crestor's trend of slow U.S. prescription growth. He said that prospect, combined with the lack of a clear positive from the trial results, may reduce some support for more-optimistic expectations for Crestor sales.
SHARE ACTION: AstraZeneca's U.S. shares fell $1.06, or 2.3 percent, to $45.63 in late morning trading.