Billionaire activist-investor Carl Icahn gives an interview on FOX Business Network's Neil Cavuto show in New York, U.S. on February 11, 2014. REUTERS/Brendan McDermid/File Photo

(Reuters) - Activist investor Carl Icahn has taken a stake in Bristol-Myers Squibb Co BMY.N, the Wall Street Journal reported, citing people familiar with the matter.

Icahn sees the drugmaker as a possible takeover target, the Journal said. The size of the stake was unclear, the paper reported.

The company’s shares spiked as much as 4.8 percent to $57.21 in late-afternoon trading on Tuesday.

Earlier in the day, Bristol-Myers said it added three directors to its board in an agreement with JANA Partners LLC, an activist investor holding less than 1 percent of the company’s stock.