In Europe, France's CAC-40 fell 0.8 percent, Britain's FTSE 100 lost 0.9 percent and Germany's DAX index gave back 1 percent.
Europe has CAC-40 fell 0.8 percent while Britain, FTSE 100 lost 0.9 percent and Germany DAX index also went down 1 percent.
The company is also testing its cancer drug Rituxan for use by rheumatoid arthritis patients .