Shares of Ariad Pharmaceuticals plunged as much as 15 percent after Sen. Bernie Sanders criticized the price of the company's leukemia drug on Twitter.



@SenSanders: Drug corporations' greed is unbelievable. Ariad has raised the price of a leukemia drug to almost $199,000 a year.

The stock ended the day down about 14.8 percent at $11.14 a share.

In a statement, Ariad said, "our pricing reflects our significant investment in R&D, our commitment to the very small, ultra orphan cancer patient populations that we serve and the associated risk with research and development."

The company added that it spent 143 percent of its total revenue in 2015 in research and development for treatments of rare cancers.



