Embattled drug company Valeant Pharmaceuticals has added three directors to its board, including an executive from activist investor Bill Ackman's hedge fund Pershing Square Capital Management.

Its shares rose more than 2 per cent in morning trading Wednesday.

The Canadian drugmaker said that Pershing Vice Chairman Stephen Fraidin has joined the board, along with pharmaceutical executive Dr. Fred Eshelman and former University of North Carolina president Thomas W. Ross. Dr. Anders Lonner also is leaving, so these moves will bump the board's size to 14 members, 12 of whom are independent.

Pershing Square holds a 6.3 per cent stake in Valeant, as one of its biggest shareholders, according to FactSet.

Fraidin is an attorney specializing in mergers and acquisitions. Eshelman is the founder and former CEO of Pharmaceutical Product Development Inc. and has worked in the pharmaceutical industry for 35 years, Valeant said.

Valeant Pharmaceuticals International Inc. is facing a Securities and Exchange Commission investigation and, separately, scrutiny from Congress over its drug pricing. CEO Michael Pearson also recently returned to work after missing two months due to some health problems.

Valeant will discuss its preliminary fourth-quarter results and update its forecast for 2016 on March 15. The company had said last month it was delaying that announcement due to Pearson's return to work.

The company also has said it would delay filing its 2015 annual report with regulators while it sorts out its former relationship with the mail-order pharmacy Philidor, which has raised questions about the accuracy of Valeant's financial reporting.

U.S.-traded shares of Valeant rose 2.2 per cent, or $1.40, to $64.55 in morning trading Wednesday. That's about a quarter of the all-time high of $263.81 that the stock reached in August, shortly before the company's practice of buying rights to old drugs and jacking up the prices came under congressional scrutiny.